GB2298693A - A linear-motion Watts linkage for a vehicle suspension - Google Patents
A linear-motion Watts linkage for a vehicle suspension Download PDFInfo
- Publication number
- GB2298693A GB2298693A GB9603972A GB9603972A GB2298693A GB 2298693 A GB2298693 A GB 2298693A GB 9603972 A GB9603972 A GB 9603972A GB 9603972 A GB9603972 A GB 9603972A GB 2298693 A GB2298693 A GB 2298693A
- Authority
- GB
- United Kingdom
- Prior art keywords
- linear motion
- motion linkage
- vehicle
- arms
- pivotal
- 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
- B60G3/00—Resilient suspensions for a single wheel
- B60G3/01—Resilient suspensions for a single wheel the wheel being mounted for sliding movement, e.g. in or on a vertical guide
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G9/00—Resilient suspensions of a rigid axle or axle housing for two or more wheels
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16H—GEARING
- F16H21/00—Gearings comprising primarily only links or levers, with or without slides
- F16H21/04—Guiding mechanisms, e.g. for straight-line guidance
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G2200/00—Indexing codes relating to suspension types
- B60G2200/30—Rigid axle suspensions
- B60G2200/314—Rigid axle suspensions with longitudinally arranged arms articulated on the axle
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G2200/00—Indexing codes relating to suspension types
- B60G2200/30—Rigid axle suspensions
- B60G2200/34—Stabilising mechanisms, e.g. for lateral stability
- B60G2200/341—Panhard rod
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G2200/00—Indexing codes relating to suspension types
- B60G2200/30—Rigid axle suspensions
- B60G2200/34—Stabilising mechanisms, e.g. for lateral stability
- B60G2200/342—Watt linkage
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G2200/00—Indexing codes relating to suspension types
- B60G2200/40—Indexing codes relating to the wheels in the suspensions
- B60G2200/464—Caster angle
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G2204/00—Indexing codes related to suspensions per se or to auxiliary parts
- B60G2204/10—Mounting of suspension elements
- B60G2204/14—Mounting of suspension arms
- B60G2204/148—Mounting of suspension arms on the unsprung part of the vehicle, e.g. wheel knuckle or rigid axle
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G2204/00—Indexing codes related to suspensions per se or to auxiliary parts
- B60G2204/40—Auxiliary suspension parts; Adjustment of suspensions
- B60G2204/421—Pivoted lever mechanisms for mounting suspension elements, e.g. Watt linkage
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G2204/00—Indexing codes related to suspensions per se or to auxiliary parts
- B60G2204/40—Auxiliary suspension parts; Adjustment of suspensions
- B60G2204/422—Links for mounting suspension elements
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G2204/00—Indexing codes related to suspensions per se or to auxiliary parts
- B60G2204/40—Auxiliary suspension parts; Adjustment of suspensions
- B60G2204/423—Rails, tubes, or the like, for guiding the movement of suspension elements
- B60G2204/4232—Sliding mounts
Description
A LINEAR MOTION LINKAGE
The invention relates to a linear motion linkage and is particularly, but not exclusively, concerned with an improved Watts-type linkage suitable for use in a motor vehicle.
A Watts-type linkage comprises a first arm mounted for pivoting about a first mounting, and a second arm mounted for pivoting about a second mounting spaced from the first mounting, the arms extending towards each other and each being pivotally connected to a respective end of an intermediate link. In a true Watts linkage the first and second arms are of equal length and pivoting of the arms about the first and second points causes a mid-point on the intermediate link to move linearly.
An object of the present invention is to provide an improved linear motion linkage.
According to the invention there is provided a linear motion linkage comprising a first arm mounted for pivoting about a first mounting point, a second arm mounted for pivoting about a second mounting point spaced from the first mounting point, an intermediate link connected by means of first and second pivotal connections to the arms at points spaced from said first and second mounting points respectively, a member connected by means of a third pivotal connection to the intermediate link at a point between the first and second pivotal connections, and restraining means in engagement with the member to control rotation of the member about the third pivotal connection during pivotal movement of the first and second arms, the restraining means being movable along the member towards and away from the third pivotal connection.
The restraining means may move along the member by, for example, sliding or rolling.
With such an arrangement, the attitude of the member can be controlled as desired during pivotal movement of the first and second arms.
Preferably the restraining means is connected to the first and second arms by first and second stabilizing links respectively.
Preferably each stabilizing link is connected to its respective arm at a point between the respective pivotal connection and the respective mounting point.
Preferably both of the stabilizing links are pivotally connected to the member at a common point.
The stabilizing means may be movable along a curved path on the member.
Preferably the two stabilizing links are connected to the respective arms at equal distances from the respective mounting points.
The present invention also provides a vehicle including a linear motion linkage according to the invention.
The linear motion linkage may comprise part of a suspension system of the vehicle.
Preferably the first and second mounting points are spaced apart by a minimum distance for a given vertical movement of the wheel carrying part to provide a compact linkage arrangement.
Preferred embodiments of the present invention will now be described by way of example with reference to the accompanying drawings in which:
Figure 1 is a diagrammatic elevation of a linear motion linkage in accordance with a first embodiment of the invention, in a first position,
Figures 2 and 3 are views of the embodiment of Figure 1 in two further positions,
Figure 4 is a perspective diagrammatic view of a suspension arrangement for a vehicle incorporating a further linear motion linkage in accordance with a second embodiment of the invention,
Figures 5 to 7 are views similar to Figures 1 to 3 showing diagrammatically a third embodiment of the invention,
Figure 8 is a perspective view of another suspension arrangement incorporating a linear motion linkage in accordance with a fourth embodiment of the invention,
Figure 9 is a diagrammatic elevation of a linear motion linkage in accordance with a fifth embodiment of the invention, and
Figure 10 is a diagrammatic elevation of a linear motion linkage in accordance with a sixth embodiment of the invention.
Referring to Fig 1, a support 10 for a linear motion linkage 111 carries spaced apart first and second mounting brackets 12, 14. A first arm 15 is connected at one end to the first mounting bracket 12 by means of a first pivotal mounting 16 and a second arm 17 is connected at one end to the second mounting bracket 14 by means of a second pivotal mounting 18. An intermediate link 19 has two ends, each of which is connected by a pivotal connection 19a, l9b to an end of a respective one of the two arms 15, 17 remote from its respective mounting bracket. The intermediate link 19 is connected at its mid-point by a pivotal connection 20 to the lower end of a vertical member 22. The vertical member 22 is formed with a slot 23 towards its upper end.A pivot pin 24, is slidable vertically in the slot 23 towards and away from the pivotal connection 20 between the member and the intermediate link 19. First and second stabilizing links 25, 26 each have one end connected to the pivot pin 24. The first stabilizing link 25 is connected to the first arm 15 by a first pivotal stabilizer connection 27 and the second stabilizing link 26 is connected to the second arm 17 by means of a second pivotal stabilizer connection 28. The arms 15, 17 are the same length and both stabilizer connections 27, 28 are the same distance from the respective mountings 16, 18.
Figure 1 shows the linkage in a mean position where the pivot pin 24 is positioned mid-way along the slot 23.
In Figure 2, the first and second arms 15,17 have moved downwards about the mountings 16, 18 thereby causing the vertical member 22 to move downwards. Such downward movement causes the member 22 to move downwards so that the top of the slot 23 moves towards the pivot pin 24, the stabilizing links 25, 26 maintaining the member 22 in or substantially in its original orientation during the movement.
Figure 3 shows the linkage after the arm 15, 17 have moved upwards about the mountings 16, 18 thereby causing the member 22 to move upwards so that the bottom of the slot 23 moves towards the pivot pin 24. Again, the stabilizing links 25, 26 maintain the vertical member 22 substantially in its original orientation.
It will be noted that the slot 23 is slightly curved.
The curvature corresponds to a locus of points on the member 22 of the pivot pin 24 during vertical movement of the member 22, with the pivotal connection 20 moving vertically along line L and the member 22 kept vertical.
By forming the slot 23 with a curvature corresponding to the said locus, the attitude of the member 22 is maintained vertical, as shown, during the pivotal movement of the arms 15, 17.
If desired, the pivotal connection 20 on the intermediate link 19 can be arranged at an off-centre position on the intermediate link 19, e.g. nearer to the pivotal connection 19a with the first arm 15 than to the pivotal connection 19b with the second arm 17. Such an arrangement can be used where maintenance of the precise original orientation of the vertical member 22 is not required, or if some controlled angular movement thereof is required during its vertical motion.
Referring now to Figure 4, an axle 30 supports a road wheel 32 at each end. The wheels 32 are driven from a drive shaft 31 via a differential 31a. The axle has a linear motion linkage 111 at its left hand end including an integral upwardly extending member 22 thereon equivalent to the vertical member 22 in Figure 1. In Figure 4, parts corresponding to those in the linkage shown in Figures 1 to 3 carry the same reference numerals. The member 22 is formed with a slot 23 in which a pivot pin 24 is slidably mounted. Stabilizing links 25, 26 are provided as in
Figures 1 to 3. First and second arms 15, 17 are provided and are pivotally connected to the body 100 of the vehicle at mounting points 16, 18. An intermediate link 19 is provided.The axle 30 is connected to the link 19 by a pivotal connection 20 in the form of a rigid pin 33 projecting from a plate 34 on the axle 30. A Panhard rod 35 provides sideways location for the axle 30. A suitable fore and aft location device such as a Watts linkage 36 or a trailing arm pivoted between the body and the axle 30 is provided at or towards the other end of the axle 30. If desired, a Watts linkage 37 having arms 37a mounted on the body and a link 37b connected to the axle 30 as shown in broken lines could be used in place of the Panhard rod 35 for sideways location. The linear motion linkage 111 controls torque reaction due to braking and/or traction at the wheels 32 and controls castor angle change.
During up and down movement of the axle 30 relative to the body, the stabilizing links 25, 26 maintain the member 22 in a substantially constant attitude thereby preventing rotation of the axle 30 during such movement. In that way change of castor angle during suspension movement is eliminated or at least minimised.
If desired the linkage in accordance with the invention could be used to control movement of a wheel carrying part such as a stub axle in an independent suspension.
Figures 5, 6 and 7 show the way in which the first and second mountings 16, 18 can be closely spaced to provide a compact linkage arrangement. Compact packaging is nearly always desirable in motor vehicle design and in Figures 5, 6 and 7 it will be seen that first and second mountings are spaced apart by approximately the diameter of a tyre 38 on the wheel 32. Even where the first and second mountings 16, 18 are closely spaced, it will be possible to control the suspension geometry over considerable wheel travel. In
Figures 5, 6 and 7 parts corresponding to parts shown in
Figures 1 to 4 carry the same reference numerals.
Looking at Figure 8, an axle 40 rotatably supports a road wheel 32 at each end. The wheels 32 are driven from a drive shaft 31 via a differential 31a. At a position adjacent its mid-length (or offset from that position) the axle 40 is provided with a linear motion linkage 211, as described above with reference to Figures 1 to 3, and has an integral upwardly extending member 22 thereon equivalent to that in Figures 1 to 3. Other parts in Figure 8 corresponding to those shown in Figures 1 to 4 carry the same reference numerals. The member 22 is formed with a slot 23 in which a pivot pin 24 is slidably mounted.
Stabilizing links 25, 26 are provided which are pivotally connected to first and second arms 15, 17 respectively, which in turn are pivotally connected to the body 100. The upwardly extending member 22 is connected to a link 19 by means of a rigid pin 42. As in Figure 4, sideways location can be provided by, for example, a Panhard rod 35 or a
Watts linkage (not shown). Fore and aft location can be provided by means of Watts linkages 43 or other suitable means adjacent the ends of the axle 40. Where Watts linkages 43 are used to provide fore and aft location, they may be smaller or larger than the linear motion linkage 211. The linear motion linkage 211 controls torque reaction due to braking and/or traction at the wheels and controls castor angle change.
Whilst specific reference has been made to the linkage in use on a motor vehicle suspension, it is envisaged that other applications of the invention are possible. In particular, it will be noted that the member 22 need not be vertical and the mountings 16,18 may be arranged one above the other so that the member 22 moves generally horizontally during pivotal movement of the arms 15, 17.
Also, the positioning of the pivotal stabilizer connections 27, 28 may be such that they do not lie at equal distances from the mountings 16,18. In such a case, the upper end of the member 22 as shown in Figure 1 can follow a controlled curved path during pivotal movement of the arms 15, 17. In that respect the term "linear motion linkage" used herein is to be treated as embracing linear type linkages capable of providing a controlled movement which may not be a straight line.
Looking at Figure 9, a linear motion linkage 311 is shown and parts corresponding to parts shown in Figures 1 to 3 carry the same reference numerals.
In Figure 9, instead of the stabilizing links 25, 26 extending between the pivot pin 24 and pivotal connections 27, 28 on the arms 15, 17, the stabilizing links 25, 26 are connected to the mountings 16, 18. Therefore, the stabilizing links 25, 26 do not move up and down during pivotal movement of the arms 15, 17. The slot 23 is therefore increased considerably in length to accommodate the vertical movement of the member 22.
In the linear motion linkage 411 of Figure 10, stabilizing links are omitted altogether and a stabilizing projection 30 on the support 10 extends into the lengthened slot 23.
Whilst the arrangements shown in Figures 9 and 10 maintain the orientation of the member 22 during pivotal movement of the arms 15, 17 the increased length of the member to accommodate the slot 23 requires a considerable amount of space. As space is usually at a premium on motor vehicles, the arrangements of Figures 9 and 10 are not ideal for use on vehicle suspensions and the arrangement shown in Figures 1 to 4 is to be preferred as the shorter member 22 occupies less space.
In Figures 1 to 9, the pivot pin 24 provides a common pivot for the stabilizing links 25, 26. However, two pivot pins 24 could be provided on a common member slidable in the slot 23. The first pivot pin 24 provides a pivotal connection for the stabilizing link 25 and the other pin 24 provides a pivotal connection for the stabilizing link 26.
The two pins 24 on the member would be arranged closely adjacent each other.
Claims (14)
1. A linear motion linkage comprising a first arm mounted
for pivoting about a first mounting point, a second arm
mounted for pivoting about a second mounting point
spaced from the first mounting point, an intermediate
link connected by means of first and second pivotal
connections to the arms at points spaced from said first
and second mounting points respectively, a member
connected by means of a third pivotal connection to the
intermediate link at a point between the first and
second pivotal connections, and restraining means in
engagement with the member to control rotation of the
member about the third pivotal connection during pivotal
movement of the first and second arms, the restraining
means being movable along the member towards and away
from the third pivotal connection.
2. A linear motion linkage according to claim 1 in which
the restraining means is connected to the first and
second arms by first and second stabilizing links
respectively.
3. A linkage according to claim 2 wherein each stabilizing
link is connected to its respective arm at a point
between the respective pivotal connection and the
respective mounting point.
4. A linear motion linkage according to claim 2 or claim 3
in which both of the stabilizing links are pivotally
connected to the member at a common point.
5. A linear motion linkage according to any foregoing claim
wherein the stabilizing means is movable along a curved
path on the member.
6. A linear motion linkage according to any one of claims 2
to 5 in which the two stabilizing links are connected to
the respective arms at equal distances from the
respective mounting points.
7. A linear motion linkage according to any preceding claim
wherein the first and second pivotal connections are at
one end of the first and second arm respectively.
8. A vehicle including a linear motion linkage according to
any preceding claim.
9. A vehicle according to claim 8 in which the linear
motion linkage comprises part of a suspension system of
the vehicle.
10.A vehicle according to claim 9 in which the member is
fast with a part of the suspension which carries a road
wheel and the first and second mounting points are on a
body or chassis of the vehicle so that when relative
movement between the wheel carrying part and the body or
chassis occurs in the vertical direction, the
restraining means maintains the wheel carrying part in a
desired attitude.
11.A vehicle according to claim 9 or claim 10 in which the
wheel carrying part is an axle which extends across the
vehicle and supports a wheel at each end thereof.
12.A vehicle according to any one of claims 9 to 11 in
which the first and second mounting points are spaced
apart by a minimum distance for a given vertical
movement of the wheel carrying part to provide a compact
linkage arrangement.
l3.A linear motion linkage constructed and arranged
substantially as described herein with reference to
Figures 1 to 3, Figure 8 or Figure 9 of the accompanying
drawings.
14. A vehicle suspension arrangement constructed and
arranged substantially as described herein with
reference to Figures 4 to 7 of the accompanying
drawings.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB9603972A GB2298693B (en) | 1995-03-10 | 1996-02-26 | A linear motion linkage |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GBGB9504939.1A GB9504939D0 (en) | 1995-03-10 | 1995-03-10 | A linear motion linkage |
| GB9603972A GB2298693B (en) | 1995-03-10 | 1996-02-26 | A linear motion linkage |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB9603972D0 GB9603972D0 (en) | 1996-04-24 |
| GB2298693A true GB2298693A (en) | 1996-09-11 |
| GB2298693B GB2298693B (en) | 1998-04-29 |
Family
ID=26306655
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB9603972A Expired - Fee Related GB2298693B (en) | 1995-03-10 | 1996-02-26 | A linear motion linkage |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2298693B (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2337491A (en) * | 1998-05-20 | 1999-11-24 | Rover Group | Beam axle control linkage |
| EP0992374A1 (en) * | 1998-10-05 | 2000-04-12 | Leonardo Enrique Maximo Aparicio | Dual input suspension system using a common spring/shock-absorber device |
| US6286846B1 (en) | 1998-10-05 | 2001-09-11 | Santiago Adrian Urguiza | Dual input suspension system using a common spring/shock-absorber device |
| EP2803514A1 (en) * | 2013-05-16 | 2014-11-19 | Deere & Company | Suspension device |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1198350A (en) * | 1967-08-16 | 1970-07-08 | Daimler Benz Ag | Improvements relating to Rear Axle Suspensions |
| GB1492655A (en) * | 1974-10-05 | 1977-11-23 | Schenck Ag Carl | Weighing mechanism |
| GB1548114A (en) * | 1978-02-20 | 1979-07-04 | Chrysler Uk | Vehicle rear suspensions |
-
1996
- 1996-02-26 GB GB9603972A patent/GB2298693B/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1198350A (en) * | 1967-08-16 | 1970-07-08 | Daimler Benz Ag | Improvements relating to Rear Axle Suspensions |
| GB1492655A (en) * | 1974-10-05 | 1977-11-23 | Schenck Ag Carl | Weighing mechanism |
| GB1548114A (en) * | 1978-02-20 | 1979-07-04 | Chrysler Uk | Vehicle rear suspensions |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2337491A (en) * | 1998-05-20 | 1999-11-24 | Rover Group | Beam axle control linkage |
| GB2337491B (en) * | 1998-05-20 | 2002-01-09 | Rover Group | Axle control linkages |
| EP0992374A1 (en) * | 1998-10-05 | 2000-04-12 | Leonardo Enrique Maximo Aparicio | Dual input suspension system using a common spring/shock-absorber device |
| US6286846B1 (en) | 1998-10-05 | 2001-09-11 | Santiago Adrian Urguiza | Dual input suspension system using a common spring/shock-absorber device |
| EP2803514A1 (en) * | 2013-05-16 | 2014-11-19 | Deere & Company | Suspension device |
| DE102013209138A1 (en) * | 2013-05-16 | 2014-11-20 | Deere & Company | hanger |
Also Published As
| Publication number | Publication date |
|---|---|
| GB9603972D0 (en) | 1996-04-24 |
| GB2298693B (en) | 1998-04-29 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 732E | Amendments to the register in respect of changes of name or changes affecting rights (sect. 32/1977) | ||
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 20050226 |