GB2172253A - A suspension system for a vehicle - Google Patents
A suspension system for a vehicle Download PDFInfo
- Publication number
- GB2172253A GB2172253A GB08506551A GB8506551A GB2172253A GB 2172253 A GB2172253 A GB 2172253A GB 08506551 A GB08506551 A GB 08506551A GB 8506551 A GB8506551 A GB 8506551A GB 2172253 A GB2172253 A GB 2172253A
- Authority
- GB
- United Kingdom
- Prior art keywords
- suspension
- vehicle
- lever
- chassis
- support
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G21/00—Interconnection systems for two or more resiliently-suspended wheels, e.g. for stabilising a vehicle body with respect to acceleration, deceleration or centrifugal forces
- B60G21/02—Interconnection systems for two or more resiliently-suspended wheels, e.g. for stabilising a vehicle body with respect to acceleration, deceleration or centrifugal forces permanently interconnected
- B60G21/04—Interconnection systems for two or more resiliently-suspended wheels, e.g. for stabilising a vehicle body with respect to acceleration, deceleration or centrifugal forces permanently interconnected mechanically
- B60G21/045—Interconnection systems for two or more resiliently-suspended wheels, e.g. for stabilising a vehicle body with respect to acceleration, deceleration or centrifugal forces permanently interconnected mechanically between wheels on different axles on the same side of the vehicle, i.e. the left or the right side
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G5/00—Resilient suspensions for a set of tandem wheels or axles having interrelated movements
- B60G5/04—Resilient suspensions for a set of tandem wheels or axles having interrelated movements with two or more pivoted arms, the movements of which are resiliently interrelated, e.g. the arms being rigid
- B60G5/047—Resilient suspensions for a set of tandem wheels or axles having interrelated movements with two or more pivoted arms, the movements of which are resiliently interrelated, e.g. the arms being rigid at least one arm being resilient, e.g. a leafspring
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G2200/00—Indexing codes relating to suspension types
- B60G2200/10—Independent suspensions
- B60G2200/13—Independent suspensions with longitudinal arms only
- B60G2200/132—Independent suspensions with longitudinal arms only with a single trailing arm
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G2400/00—Indexing codes relating to detected, measured or calculated conditions or factors
- B60G2400/60—Load
- B60G2400/61—Load distribution
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G2800/00—Indexing codes relating to the type of movement or to the condition of the vehicle and to the end result to be achieved by the control action
- B60G2800/21—Traction, slip, skid or slide control
- B60G2800/214—Traction, slip, skid or slide control by varying the load distribution
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Vehicle Body Suspensions (AREA)
Abstract
The invention is concerned with suspension devices for vehicles. The primary aspect of the invention relates to vehicles of the kind in which there are two vehicle supports, usually road wheels, but possibly tracks or skids, one behind the other, and there is provision whereby when one support rises relatively to the chassis (for instance if it rides over an obstacle) the other support is pressed down. This may be achieved by two transmission levers connected respectively to the two supports for turning when the respective support rises, and a linkage connecting the two transmission levers together. According to a secondary aspect of the invention in a suspension system for a vehicle which has a torsion rod connected between a suspension lever and a reaction member, there is provision for varying the effective length, and therefore the compliance of the torsion rod. <IMAGE>
Description
SPECIFICATION
A suspension system for a vehicle
The invention is concerned with vehicle suspension systems, and more particularly is intended to be used on road vehicles, although it could also be used on other vehicles e.g.
rail vehicles. There are two general aspects of the invention, the first of which is applicable to vehicles in which there are two or more wheels, or sets of wheels (or other supports e.g. tracks or skids) spaced from each other lengthwise of the vehicle, e.g. front and rear wheels, and the second of which is applicable to any wheel or other support arrangement.
According to a first aspect of the invention a suspension for a vehicle comprises two vehicle supports (e.g. road wheels, tracks or skids) spaced lengthwise of the vehicle and a resilient suspension device active between each vehicle support and the vehicle chassis, there being a mechanism connected so as to transmit force between the suspension devices in a manner such that any tendency for one vehicle support to rise relatively to the chassis applies a force tending to press the other vehicle support downwardly relatively to the chassis.
In a preferred construction, a transmission lever is connected to each suspension device so that the relative motion between each support and the chassis or body permitted by flexing of the suspension produces turning of the transmission lever, there being a linkage connecting the two transmission levers in such a manner that the turning of one lever in one direction due to a reduction in the height of the chassis or body relatively to the support appertaining to to that lever tends to turn the other lever in a direction such as to produce an increase in the height of the chassis relatively to the support appertaining to that other lever.
The effect of the arrangement of the suspension system in accordance with the first aspect of the invention is that whenever a vehicle support encounters an obstacle, so that that support tends to rise and the chassis tends to descend relatively to that support, a force is applied through the linkage and transmission levers tending to cause the other vehicle support to descend and the chassis tends to ascend relatively to that other vehicle support. To put this even more simply, as one support rises, the other is pressed down. This arrangement is very useful in that it helps to ensure that both the supports are held in engagement with the ground even when the vehicle encounters obstacles or potholes.
It is to be understood that references in this specification to the vehicle chassis are intended to include the body of the vehicle in constructions wherein there is no chassis which is separate from the body, i.e. monocoque construction.
Preferably each vehicle support is carried on a suspension lever pivoted about an axis on the chassis, the transmission lever appertaining to that vehicle support being pivoted about the same axis and connected to the suspension lever in a manner which prevents substantial angular displacement between the suspension lever and the transmission lever. It is preferred to provide a torsion rod extending between the suspension lever and the transmission lever, the torsion rod being jour nalled in a bearing or bearings to provide the pivotal mounting of the suspension lever and the elasticity of the rod in torsion providing the resilient force of the suspension device.
With this arrangement, there is provision for some angular motion between the suspension lever and the transmission lever to provide the resilient effect of the suspension device, but this is relatively small. In practice, the link will transmit force between the two suspension devices and therefore the resilient force resisting raising of one vehicle support relatively to the chassis will be divided between the two torsion rods of the two suspension devices.
This is because as a torque is applied to the torsion rod appertaining to one vehicle support, due to that support attempting to rise, torque is also transmitted through the link and the other transmission lever to the other torsion rod, the turning of which is opposed by the resistance of the other vehicle support to lower (brought about by its engagement with the ground).
According to a second aspect of the invention, which is applicable to all kinds of vehicles, a vehicle suspension system has a vehicle support attached to a suspension lever, there being a torsion rod connected between the suspension lever and a reaction member, so that the resilient force resisting movement of the vehicle support relatively to the chassis is provided by the elasticity in torsion of the torsion rod between the suspension lever and the reaction member and is characterised by the fact that there is provision for varying the distance between the suspension lever and the reaction member to vary the effective length and therefore the compliance of the torsion rod.
Preferably the torsion rod extends transversely of the vehicle and the reaction member is adjustable transversely of the vehicle to vary the distance between the reaction member and the suspension lever.
The two aspects of the invention may be combined in a single embodiment where the two transmission levers of the first aspect are two reaction members of the second aspect, the second aspect in that case being applied to the two suspensions of a vehicle with two vehicle supports spaced lengthwise of the vehicle. An embodiment in which both aspects of the invention are present will now be de scribed by way of example only, with reference to the accompanying drawings in which:
Figure 1 is a diagrammatic plan view of two sets of road wheels forming a close-coupled pair on a vehicle,
Figure 2 is a diagrammatic side view of the arrangement shown in Figure 1, and
Figure 3 is a diagrammatic view looking in the direction of arrow III in Figure 2.
In this particular example, the invention is described with reference to a vehicle having a chassis, of which two transverse beams 10 and 12 are illustrated. These beams are spaced longitudinally of the vehicle. A front pair of -road wheels14 is suspended from the front beam 10, and a rear pair of road wheels 16 is suspended from the rear beam 12. It will be seen that the two pairs of road wheels 14 and 16 are arranged quite close to each other, in what is commonly known as a closecoupled arrangement. It will be appreciated, that the road wheel arrangement is duplicated at the other side of the vehicle. In the case ofa small trailer, only the road wheels 14 and 16 and their counterparts at the other side of the vehicle will be provided adjacent to the centre of the length of the vehicle.With a larger trailer vehicle, there will be other road wheels, not shown, and these may have similar suspension arrangements to that illustrated in the drawings or alternative suspension arrangements may be employed.
The road wheels 14 are mounted on a common axle 18 which is carried at the distal end of a suspension lever 20. This lever is bifurcated at its proximal end, where it is secured in a non-rotatable manner on a torsion rod 22. The torsion rod 22 extends transversely of the vehicle closely adjacent to the beam 10, and is journalled in a pair of bearings 24 and 26 which are secured to the beam 10.
Hence, the suspension lever 20 is pivoted about the axis provided by the bearings 24 and 26. The arrangement of the road wheels 14 on the suspension lever 20 permits movement of the road wheels relatively to the chassis of the vehicle, the axle 18 being able to turn about an arc 28 shown in Figure 2. If the road wheels 14 encounter an obstacle, they tend to rise over that obstacle but the inertia of the chassis causes it to tend not to rise, so that there is the relative motion between the road wheels 14 and the chassis, provided by the suspension arrangement. If the torsion rod 22 merely acted as an axle freely journalled in the bearings 24 and 26, the suspension would have virtually no stiffness.
A transmission lever 30 is secured on the torsion rod 22, in such a manner that it is possible to adjust the position of the transmission lever along the torsion rod, between the fixed bearing 24 and the inner edge of the bifurcated portion of the suspension lever 20. As shown in Figure 2, the transmission lever 30 projects upwardly from the axis provided by the torsion rod 22.
The suspension arrangement for the road wheels 16 is identical with that described for the road wheels 14 (and similar parts have therefore been given the same reference numeral with the suffix a) but the transmission lever 30a is located on the torsion rod 22a, so that it extends downwardly from the axis provided by the torsion rod. Each of the transmission levers 30 and 30a has a swivel block 32 and 32a, and a link rod 34 extends between the transmssion levers 30 and 30a, and is secured in the swivel blocks 32 and 32a. The link 34 therefore provides for a fixed distance between the distal ends of the transmission levers 30 and 30a although it is possible to adjust the position of the swivel block 32 or 32a on the link rod 34 within limits, to vary the distance between the transmission levers.It will be appreciated,that if the effective length of the link rod 34 is decreased, then the transmission lever 30 will be turned in a clockwise direction and the transmission lever 32 will be turned in anticlockwise direction. As a result, the suspension levers 20 and 20a will press the road wheels 14 and 16 downwardly, or to be more precise, will increase the vertical distance between the chassis and the axles of the road wheels. In fact, the provision for changing the effective length of the link rod 34 is the means whereby the height of the chassis above the road wheel axles can be adjusted if required.
In order to understand the operation of the suspension system, let it be considered that the transmission lever 30 is fixed to the beam 10. Then as the road wheel 14 attempts to rise, the suspension lever 20 will apply a turning moment to the torsion rod 22, and raising of the road wheels will only be possible as permitted by twisting of the torsion rod 22 between its anchor position in the transmission lever 30 and the position at which it is secured in the proximal end of the suspension lever 20. In other words, the resilient load required by the suspension system to restrict upward displacement of the road wheels relatively to the chassis is provided by the elasticity in torsion of the effective length of the torsion rod 22.
Now if the position at which the transmission lever 30 is fixed to the beam 10 is adjusted, so as to vary the effective length of the torsion rod 22, it will be appreciated that the compliance of the torsion rod 22 in torsion is altered. The longer the effective length of the torsion rod (i.e. the nearer the transmission lever 30 to the fixed bearing 24) the greater will be the compliance of the torsion rod, and hence the lower the stiffness of the suspension system. It is in fact possible to secure the transmission lever 30 to the beam 10 if only a single pair of road wheels is being used, though in that case, the link rod 34 is not required, and in fact the transmission lever 30 merely acts as a reaction member for the torsion rod 22.
In the construction which is illustrated, the transmission lever 30 is not secured to the beam 10, but instead, its turning about the axis provided by the torsion rod is restricted by the attachment of the link 34 to the transmission lever 30a of the rear suspension system. When the suspension arm 20 turns due to raising of the road wheels 14, this turning motion is transmitted through the torsion rod 22 to the transmission lever 30, and then through the link 34 to the transmission lever 30a. However, whereas this motion involves turning of the transmission lever 30 in an anti-clockwise direction, the lever 30a is turned in a clockwise direction-this is the result of having one transmission lever pointing upwardly and the other pointing downwardly from their respective axis.Turning of the transmission lever 30a in a clockwise direction causes the suspension lever 20a to attempt to turn in a clockwise direction and to force the road wheels 16 downwardly. In other words, the two suspension systems for the road wheels 14 and 16 are connected together by the transmission levers and the link rod 34 in such a manner that any upward motion of the road wheels 14 creates a force tending to press the road wheels 16 downwardly and vice versa. This arrangement ensures that the two pairs of road wheels are maintained in engagement with the road surface even though the wheels of one pair may be encountering an obstacle or falling into a pothole.
By virtue of this arrangement, both torsion rods provide the resilient loading for each of the pairs of road wheels. To put this another way, the reaction "member" for the front pair of road wheels 14 is actually the rear pair of road wheels 16, since the suspension system for the front pair of road wheels can be considered as being: the suspension lever 20, the torsion rod 22, the transmission lever 30, the link rod 34, the transmission lever 32a, the torsion rod 22a and the suspension lever 20a.
In other words, the spring loading of the suspension system is divided between the two torsion rods 22 and 22a.
It will be appreciated, that it is possible to couple together in this way more than two road wheels or road wheel sets. For instance, in addition to the transmission lever 30, an additional transmission lever 30b indicated in chain-dotted lines in Figure 2 could be secured on the torsion rod 22, with the lever 30b projecting downwardly from that torsion rod.
A link rod 34b is then attached at its rear end to the transmission lever 30b, and at its front end (not shown) to another transmission lever pointing upwardly from a preceding road wheel or road wheel system. Similarly, a transmission lever 30c could be secured to the torsion rod 22a, with the lever 30c pointing upwardly, and a link rod 34c connected at its front end to the lever 30c and at its rear end (not shown) to another transmission lever similar to the lever 30a, appertaining to a further road wheel or road wheel set.
The fixed bearings 26 and 26a are each spherical bearings, which in addition to providing the journal mounting for the torsion rod 22 or 22a, also permit some bending of the torsion rod as indicated by the arrows 40 and 42 in Figure 3. Hence, where there are two road wheels 14 in tandem as illustrated in the drawings, it is possible for one of these to rise or fall relatively to the other within small limits provided by the spherical bearing 26.
It will be appreciated, that whilst twin or tandem wheels have been illustrated in the specific embodiment, the invention could equally be applied to single road wheels. It will also be appreciated, that similar suspension arrangements could be applied to skids or tracks rather than road or rail wheels.
Claims (7)
1. A suspension for a vehicle comprising two vehicle supports spaced lengthwise of the vehicle and a resilient suspension device active between each vehicle support and the vehicle chassis, there being a mechanism connected so as to transmit force between the suspension devices in a manner such that any tendency for one vehicle support to rise relatively to the chassis applies a force tending to press the other vehicle support downwardly relatively to the chassis.
2. A suspension for a vehicle as claimed in
Claim 1, in which a transmission lever is connected to each suspension device so that the relative motion between each support and the chassis or body permitted by flexing of the suspension produces turning of the transmission lever, there being a linkage connecting the two transmission levers in such a manner that the turning of one lever in one direction due to a reduction in the height of the chassis or body relatively to the support appertaining to that lever tends to turn the other lever in a direction such as to produce an increase in the height of the chassis relatively to the support appertaining to that other lever.
3. A suspension for a vehicle as claimed in
Claim 2, in which each vehicle support is carried on a suspension lever pivoted about an axis on the chassis, the transmission lever appertaining to that vehicle support being pivoted about the same axis and connected to the suspension lever in a manner which prevents substantial angular displacement between the suspension lever and the transmission lever.
4. A suspension for a vehicle as claimed in
Claim 3, in which a torsion rod is provided extending between the suspension lever and the transmission lever, the torsion rod being journalled in a bearing or bearings to provide the pivotal mounting of the suspension lever and the elasticity of the rod in torsion providing the resilient force of the suspension device.
5. A vehicle suspension system having a vehicle support attached to a suspension lever, there being a torsion rod connected between the suspension lever and a reaction member, so that the resilient force resisting movement of the vehicle support relatively to the chassis is provided by the elasticity in torsion of the torsion rod between the suspension lever and the reaction member is characteristed by the fact that there is provision for varying the distance between the suspension lever and the reaction member to vary the effective length and therefore the compliance of the torsion rod.
6. A vehicle suspension as claimed in Claim 5, in which the torsion rod extends transversely of the vehicle and the reaction member is adjustable transversely of the vehicle to vary the distance between the reaction member and the suspension lever.
7. A suspension for a vehicle constructed and arranged substantially as herein described with reference to the accompanying drawings.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB08506551A GB2172253B (en) | 1985-03-13 | 1985-03-13 | A suspension system for a vehicle |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB08506551A GB2172253B (en) | 1985-03-13 | 1985-03-13 | A suspension system for a vehicle |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB8506551D0 GB8506551D0 (en) | 1985-04-17 |
| GB2172253A true GB2172253A (en) | 1986-09-17 |
| GB2172253B GB2172253B (en) | 1989-02-15 |
Family
ID=10575944
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08506551A Expired GB2172253B (en) | 1985-03-13 | 1985-03-13 | A suspension system for a vehicle |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2172253B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2245234A (en) * | 1990-05-15 | 1992-01-02 | James Leslie Holden | A suspension system for a vehicle |
| CN102275477A (en) * | 2010-06-12 | 2011-12-14 | 中集车辆（集团）有限公司 | Semitrailer hanger, semitrailer and assembly method of semitrailer |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB808673A (en) * | 1955-08-01 | 1959-02-11 | Daimler Benz Ag | Improvements relating to a spring suspension and compensating arrangement for the road wheels of vehicles |
| GB882954A (en) * | 1960-05-27 | 1961-11-22 | Cranes Dereham Ltd | Improvements in suspension systems for road vehicles |
| GB1115690A (en) * | 1966-05-10 | 1968-05-29 | Daimler Benz Ag | Improvements relating to arrangements for balancing the loading on two rear axles of a vehicle in tandem |
| GB1177848A (en) * | 1967-09-28 | 1970-01-14 | Moulton Development Ltd | Improvements in Vehicle Suspensions |
| GB1212447A (en) * | 1967-10-17 | 1970-11-18 | Volvo Ab | Improvements in or relating to suspension systems of traction vehicles for semitrailers |
| GB1303239A (en) * | 1970-10-06 | 1973-01-17 | ||
| GB2027401A (en) * | 1978-07-28 | 1980-02-20 | Kellwood Co | Stabilising suspensions for vehicles |
| GB2057984A (en) * | 1979-08-24 | 1981-04-08 | Goth J | Vehicle axle mounting arrangement |
| EP0045411A2 (en) * | 1980-08-04 | 1982-02-10 | Eaton Corporation | Equalized four-spring tandem axle suspension |
-
1985
- 1985-03-13 GB GB08506551A patent/GB2172253B/en not_active Expired
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB808673A (en) * | 1955-08-01 | 1959-02-11 | Daimler Benz Ag | Improvements relating to a spring suspension and compensating arrangement for the road wheels of vehicles |
| GB882954A (en) * | 1960-05-27 | 1961-11-22 | Cranes Dereham Ltd | Improvements in suspension systems for road vehicles |
| GB1115690A (en) * | 1966-05-10 | 1968-05-29 | Daimler Benz Ag | Improvements relating to arrangements for balancing the loading on two rear axles of a vehicle in tandem |
| GB1177848A (en) * | 1967-09-28 | 1970-01-14 | Moulton Development Ltd | Improvements in Vehicle Suspensions |
| GB1212447A (en) * | 1967-10-17 | 1970-11-18 | Volvo Ab | Improvements in or relating to suspension systems of traction vehicles for semitrailers |
| GB1303239A (en) * | 1970-10-06 | 1973-01-17 | ||
| GB2027401A (en) * | 1978-07-28 | 1980-02-20 | Kellwood Co | Stabilising suspensions for vehicles |
| GB2057984A (en) * | 1979-08-24 | 1981-04-08 | Goth J | Vehicle axle mounting arrangement |
| EP0045411A2 (en) * | 1980-08-04 | 1982-02-10 | Eaton Corporation | Equalized four-spring tandem axle suspension |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2245234A (en) * | 1990-05-15 | 1992-01-02 | James Leslie Holden | A suspension system for a vehicle |
| CN102275477A (en) * | 2010-06-12 | 2011-12-14 | 中集车辆（集团）有限公司 | Semitrailer hanger, semitrailer and assembly method of semitrailer |
| CN102275477B (en) * | 2010-06-12 | 2014-05-07 | 中集车辆（集团）有限公司 | Semitrailer hanger, semitrailer and assembly method of semitrailer |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2172253B (en) | 1989-02-15 |
| GB8506551D0 (en) | 1985-04-17 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19940313 |