CLAUSEN, Nicolai Alexander (Rønnegade 24, st.th, København Ø, DK-2100, DK)
LARSEN, Ebbe Jannes (Emdrupvej 20, 1 th, København Ø, DK-2100, DK)
NIELSEN, Bjarke (Skolegade 32, Løsning, DK-8720, DK)
CLAUSEN, Nicolai Alexander (Rønnegade 24, st.th, København Ø, DK-2100, DK)
LARSEN, Ebbe Jannes (Emdrupvej 20, 1 th, København Ø, DK-2100, DK)
CLAIMS
1. Arrangement for the suspension of a number of wheels (7) on a chassis with opposite sides comprising two wheel suspensions (1), where each wheel suspension (1) is arranged on each side, where each wheel suspension (1) comprises a suspension frame (2), two support frames (3) and a first spring arrangement (4), and where the suspension frame (2) is connected to the chassis, where each support frame (3) is provided with an arrangement of at least three connection points (8, 9, 10), where the support frame (3) is rotably connected to the suspension frame (2) at a first connection point (8), where the support frame (3) is connected to a wheel axle at a second connection point (9), where the support frame (3) is connected to the first spring arrangement (4) at a third connection point (10), and where the third connection point (10) is arranged below the first and second connection point (8, 9) on the support frame (3), characterised in that the support frames (3) are arranged on the suspension frame (2) in such a manner that the distance between the second connection points (9) of the adjacent support frames (3) is shorter than the distance between the first connection points (8) of the adjacent support frames (3).
2. Arrangement according to claim 1, characterised in that each support frame (3), furthermore, comprises a fourth connection point in which is arranged a second spring arrangement connecting the support frame (3) with the chassis.
3. Arrangement according to any of the claims 1-2, characterised in that the suspension frame (2) is provided with a number of stop members (11) adapted to pre- vent free rotation of the support frame (3) around the first connection point (8).
4. Arrangement according to any of the claims 1-3, characterised in that the suspension frame (2) is provided with means for reinforcement (14).
5. Arrangement according to any of the claims 1-4, characterised in that the suspension frame (2) is provided with a recess (13) at a lower edge.
6. Arrangement according to any of the claims 1-5, characterised in that the suspension frame (2) is shaped by a number of frame parts (31).
7. Arrangement according to any of the claims 1-6, characterised in that the first and second spring arrangement (4) comprises a linear push unit or pull unit.
8. Arrangement according to any of the claims 1-7, characterised in that the first and second spring arrangement (4) comprise one of the following or a combination of the following:
- Spiral spring, coil spring, helical spring, helical twist spring, screw spring,
- Disc spring, cup spring, plate spring,
- Leaf spring, steel plate spring, plate spring, laminated spring, flat spring,
- Shock absorber, shock reducer, - Air buffer; air dashpot, air cushion,
- Oil shock absorber,
- Resilient material, e.g. rubber pad. |
Arrangement for the suspension of a number of wheels
Field of the Invention
The present invention relates to an arrangement for the suspension of a number of wheels on a chassis with opposite sides comprising two wheel suspensions, where each wheel suspension is arranged on each side, where each wheel suspension comprises a suspension frame, two support frames and a first spring arrangement and where the suspension frame is connected to the chassis, where each support frame is provided with an arrangement of at least three connection points, where the support frame is rotably connected to the suspension frame at a first connection point, where the support frame is connected to a wheel axle at a second connection point, where the support frame is connected to the first spring arrangement at a third connection point, and where the third connection point is arranged below the first and second connection point.
Background of the Invention
When individuals want to transport large amounts of goods or animals they have to invest in a truck or a trailer. Unless transport of large amounts of goods or animals is needed regularly, investing in a truck is wasteful. Furthermore, it is troublesome to use the truck for daily transport, because of the truck's dimension and poor road holding qualities.
Hence most people buy trailers, which may be connected to the towing hook of a passenger car, when the need for transporting large amounts of goods or animals arises.
Today trailers differ in dimension and use, e.g. large trailers exist for the transporting of horses, bikes, cars, garden vehicles or the like, while small trailers are used for transporting goods (e.g. when people move from one house to another).
The car road holding qualities are reduced when towing a trailer. Thus trailer manufacturers have tried to enhance the trailer road holding qualities. One way to enhance these qualities is to provide the wheels of the trailer with a suspension arrangement, hence slight road roughness is taken up by the suspension arrangement, and the trailer travels more smoothly on the road, hence improving the car road holding qualities.
To load goods onto a trailer the user has to move everything from the ground and into the trailer bed. This can be troublesome and hard work and sometimes even impossible due to the weight of the goods, vehicle or animal. Hence some trailers are provided with approach ramps, whereby e.g. a vehicle can drive up by itself, or goods can be loaded by means of e.g. a sack truck.
The approach ramps make it easier to load the trailer, however, they are disadvantageous as they are kept in the trailer and thus take up space on the trailer bed. Further- more, they are purchased separately, which adds to the total cost of the trailer.
Tilting of the trailer bed practically renders approach ramps obsolete. Tilting of the trailer bed is carried out mechanically or manually and makes it easier for the user to load large amounts of goods, a vehicle or an animal.
EP-A1-0930181 shows and describes an arrangement for raising or lowering the trailer bed by means of a cylinder. The stop members prevent the suspension frame/wheels from rotating freely around a connection point at the chassis. Furthermore, the two suspension frames rotate in the same direction, and by means of this arrangement it is possible to control the tilting of the trailer bed.
DE 1 280 685 shows a suspension arrangement for a lorry or a truck. This suspension arrangement has an adjustable ground clearance. The two suspension frames in each side rotate in opposite direction and the suspension frames is connected to a common spring and damper arrangement. This arrangement is well suited for a suspension with relatively large wheels as the wheel centre is spaced apart, or for a suspension where a large distance between the axels of buggy is intended.
Object of the Invention
It is the object of the present invention to provide an arrangement for the suspension of a number of wheels on a chassis, where the arrangement provides for both the suspen- sion of the wheels and the tilting of the trailer bed.
Another object of the present invention is to provide an arrangement, which can be mounted on trailers of different dimension.
Yet another object of the present invention is to provide an arrangement providing a low trailer clearance height.
Description of the Invention
The above listed objects of the present invention are obtained by means of an ar- rangement as described in the preamble of claim 1, and where the support frames are arranged on the suspension frame in such a manner that the distance between the second connection points of the adjacent support frames is shorter than the distance between the first connection points of the adjacent support frames.
Arranging the support frames with this shorter distance between the support frames is determined by the fact that the distance between the wheels should be as little as possible. This is due to the fact that it is difficult to turn a trailer when the distance between the wheels is too large, and furthermore it is possible to obtain a high tilt angle of the trailer bed, if the wheels/support frames are positioned relatively close to each other.
To provide an arrangement which provides a low trailer clearance height the support frames are arranged on the suspension frame in such a manner that the distance between the second connection points of the adjacent support frames is shorter than the distance between the first connection points of the adjacent support frames.
This configuration of the support frames in relation to the suspension frame allows the trailer manufacturer to manufacture a compact arrangement.
The arrangement for the suspension of a number of wheels on a chassis with opposite sides comprises two wheel suspensions, where each wheel suspension is arranged on each side on the chassis, thereby avoiding the use of a through-going wheel axle; hence making it possible to avoid the width consideration of the trailer, when mounting an arrangement according to the present invention on a trailer.
The arrangement makes the suspension arrangement more flexible and allows trailer manufacturers to use standard components for the suspension arrangement regardless of the trailer type.
The wheel suspension comprises a suspension frame, two support frames and a first spring arrangement, where the suspension frame is connected to the chassis, and the two support frames are mounted on the suspension frame and connected by means of the first spring arrangement.
This configuration allows each wheel suspension to absorb different impacts of the two wheels connected to the support frame. Due to the wheel suspensions in both sides of the chassis of the trailer, the trailer's front and back wheel are more or less independent of each others movements, and the wheels are sideways totally independent. This causes e.g. the wheels to follow any bumps or holes in the road, meanwhile the three other wheels remain on the road surface either in the same vertical position or in different vertical positions.
Furthermore, the arrangement allows opposite rotation of the two support frames, thus causing opposite displacement of the wheels connected to the support frame hence the arrangement can be used when tilting the trailer bed.
To obtain an arrangement for the suspension of a number of wheels on a chassis, where the arrangement provides for both the suspension of the wheels and the tilting of the trailer bed, the third connection point is arranged below the first and the second
connection point on the support frame, and furthermore the angle between the line between the first connection point and the second connection point and the line between the third connection point and the second connection point are approximately perpendicular.
The angle between the line between the first connection point and the second connection point and the line between the third connection point and the second connection point influence the tilting motion of the trailer bed.
The angle between the line between the first connection point and the second connection point and the line between the third connection point and the second connection point can both be less than 90 degrees or larger than 90 degrees.
According to one embodiment of the present invention each support frame, further- more, comprises a fourth connection point in which is arranged a second spring arrangement connecting the support frame with the chassis. The second spring arrangement could comprise a shock absorber, whereby it is only necessary for the first spring arrangement to comprise a spring for the arrangement to work properly.
As an alternative to a fourth connection point to which the second spring arrangement is connected, the third connection point could be connected along with the second spring arrangement.
To prevent uncontrolled rotation of the support frame around the first connection point, the suspension frame is provided with a number of stop members adapted to prevent free rotation of the support frame around the first connection point.
The stop members are arranged in such a manner on the suspension frame that they prevent the support frame from rotating more than 30-50 degrees either way from a non-operating position of the support frame.
As the spring arrangement connects the two support frames, the first stop member acting on a first support frame equally prevents further rotation of the second support frame, and vice versa the second stop member acting on the second support frame equally prevents further rotation of the first support frame. The stop members can therefore be arranged in pairs either below or above the support frame.
The stop members are provided with a contact surface, which rests against a part of the support frame, when the support frame is rotated 30-50 degrees from the non- operating position of the support frame.
As an alternative to stop members with contact surfaces, a torsion spring or bar, which is integrated in the assembly of the first connection point between the support frame and the suspension frame, could be used.
To ensure that the suspension frame absorbs the torque transmitted from the wheels via the support frame, the suspension frame is provided with means for reinforcement.
According to one embodiment of the present invention the means for reinforcement could be one or more of the following: ribs, fins, gills, ledges, feathers or profiles, which are arranged longitudinally or transversally on a side of the suspension frame.
An alternative to reinforcing the suspension frame is to provide the suspension frame in one sheet of material with bends. The bending of the material provides the rigidity of the suspension frame. According to one preferred embodiment of the present inven- tion the suspension frame is provided in one piece with a number of bends along one edge part, hence the bends allow the suspension frame to be mounted around a girder of the chassis.
To ensure that the arrangement provides a low trailer clearance height, the suspension frame is provided with a recess at a lower edge, wherein the spring arrangement is arranged entirely or partly. The recess is shaped to receive the spring arrangement, particularly when tilting the frailer bed.
To further minimize the height of the arrangement the axis of the spring arrangement is stunted so the spring arrangement, which is arranged between the third connection points of two support frames in a non-operating position is positioned higher than a straight line connecting the third connection points of the two support frames.
According to one embodiment of the present invention the suspension frame is shaped as one unit, whereto it is possible to connect two support frames. To mount the suspension frame on the subsurface of the longitudinal girders of the chassis the suspension frame is shaped by a number of frame parts. According to a preferred embodiment of the present invention, where the suspension frame is shaped by a number of frame parts, the suspension frame is shaped by two bearing frames. Each bearing frame is mounted on the subsurface of the chassis and is rotably connected to the first connection point of the support frame.
Using bearing frames allows the trailer manufacturer to:
Move the arrangement further underneath the chassis, hence making the width of the trailer equal to the width of the trailer bed.
Increase the trailer manufacturer's possibilities to produce the arrangement with standard components, hence making the arrangement less costly to produce.
Increases the rigidity of the suspension frame, because each bearing frame has a surface in contact with the subsurface of the chassis. - Increase the distance between the support frames, because the axes connecting the support frame and the bearing frame is longer, hence the torque caused by the sup- port frame is absorbed better.
Mount the suspension frame in-situ.
The first and second spring arrangements comprise a linear push unit or pull unit. According to one preferred embodiment of the present invention the first spring arrange- ment is a linear push unit due to the fact that use of a linear push unit allows the manufacturer to produce a very compact arrangement and provides the best possibility of mounting the arrangement on different types of chassis'.
To provide the suspension for the wheels on a chassis the first and second spring arrangements comprise one of the following or a combination of the following:
- Spiral spring, coil spring, helical spring, helical twist spring, screw spring, - Disc spring, cup spring, plate spring,
- Leaf spring, steel plate spring, plate spring, laminated spring, flat spring,
- Shock absorber, shock reducer,
- Air buffer; air dashpot, air cushion,
- Oil shock absorber, - Resilient material, e.g. rubber pad
According to a preferred embodiment of the present invention the first spring arrangement comprises a shock absorber enclosed by e.g. a coil spring. This combination provides a favourable transmission of power and ensures the necessary suspension of the wheels of the trailer. Using a coil spring, furthermore, provides the possibility of controlling the spring stiffness; hence the angular motion of the support frames can be controlled.
The transmission of power in the spring arrangement is dependent on the velocity by which the wheels are affected. The weight distribution between the front and the back wheel connected to the arrangement is always 50/50 because of the wheel's relatively vertical motion in relation to each other. Both wheels are affected by a force of similar size, however, the forces are oppositely directed, hence the wheels always maintain contact with the ground, if the rotation of the support frame is not otherwise limited.
According to one embodiment of the present invention the first spring arrangement is replaced by a solid connection, which is shorter than the axle of the first spring arrangement, hence the wheels are drawn up under the chassis. This feature is advantageous, when the trailer is stored or when a low loading height is required or during transport requiring a stable and compact trailer.
According to one embodiment of the present invention the first spring arrangement is provided with a clamp unit, which can be mounted on the spring arrangement, hence preventing the extension and retraction of the spring in the spring arrangement. The following two configurations exist: the wheels are drawn up under the chassis, when the clamp prevents extension of the spring, hence lowering the trailer bed.
- the wheels are pushed down from the chassis, when the clamp prevents retraction of the spring, hence lifting the trailer bed.
Description of the Drawing
In the following the invention will be described with reference to the accompanying drawing, where:
Fig. 1 shows a side view of a wheel suspension,
Fig. 2 shows a plan view of the wheel suspension, Fig. 3 shows a side view of a support frame,
Fig. 4 shows a side view of a wheel suspension with stop members,
Fig. 5 shows a side view of a wheel suspension,
Fig. 6 shows a back side view of a wheel suspension,
Fig. 7 shows an alternative suspension frame, and Fig. 8 shows an alternative wheel suspension.
Detailed Description of the Invention
Fig. 1 and 2 shows a wheel suspension 1 comprising a suspension frame 2, two support frames 3 and a first spring arrangement 4. The suspension frame 1 is connected to the chassis (not shown). The two support frames 3 are connected to the suspension frame 2. The first spring arrangement 4 comprises a shock absorber 5 enclosed by a coil spring 6. The wheels 7 are connected to the support frames 3.
Fig. 3 shows a support frame 3 which is provided with an arrangement of at least three connection points 8, 9, 10, where support frame 3 is rotably connected to the suspension frame (not shown) at a first connection point 8, where the support frame 3 is con-
nected to a wheel axle (not shown) at a second connection point 9, where the support frame 3 is connected to the first spring arrangement (not shown) at a third connection point 10, and where the third connection point 10 is arranged below the first and second connection point 8, 9 on the support frame 3.
Fig. 1 and 2 show that the support frames 3 are arranged on the suspension frame 2 in such a manner that the distance between the second connection points 9 of the adjacent support frames 3 is shorter than the distance between the first connection points 8 of the adjacent support frames 3. Hence the arrangement is symmetrical around a cen- tral vertical axis.
Fig. 4 shows a wheel suspension 1 with stop members 11 mounted on the suspension frame 2 above the support frames 3. The stop members 11 prevent free rotation of the support frames 3. The first spring arrangement 4 is shown with a stunted axle 12, hence the first spring arrangement 4 is arranged in the recess 13 of the suspension frame 2 and thereby the height of the wheel suspension 1 is reduced.
Fig. 5 shows a wheel suspension 1 where the wheels 7 are positioned in different positions and the spring arrangement 4 is moved to the right side of recess 13. This con- figuration occurs either when the trailer bed (nor shown) is tilted or if the left wheel 7 is affected by a large bump on the road.
Fig. 6 shows a back side of a wheel suspension 1, where it is possible to see that the suspension frame 2 is provided with means for reinforcement in the shape of ribs 14. It is also obvious that the suspension frame 2 is provided with a centrally arranged recess 13, wherein the spring arrangement 4 is positioned.
Fig. 7 shows an alternative suspension frame 20, which is shaped by a single sheet of material 21, which is bend twice along two bend lines 22, 23. The bends provide the rigidity of the suspension frame 20. In the shown embodiment of the present invention the suspension frame 20 can be mounted around a girder (not shown) of the chassis (not shown).
Fig. 8 shows an alternative wheel suspension 30, where the suspension frame is provided by two bearing frames 31, which are connected to the subsurface of a girder 32 of the chassis (not shown). The support frames 3 are connected to the bearing frames 31.