GB1601444A - Spring devices suitable for vehicle axles - Google Patents

Spring devices suitable for vehicle axles Download PDF

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Publication number
GB1601444A
GB1601444A GB10221/78A GB1022178A GB1601444A GB 1601444 A GB1601444 A GB 1601444A GB 10221/78 A GB10221/78 A GB 10221/78A GB 1022178 A GB1022178 A GB 1022178A GB 1601444 A GB1601444 A GB 1601444A
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United Kingdom
Prior art keywords
floating members
spring
outer cover
chamber
floating
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.)
Expired
Application number
GB10221/78A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
TRENKAMP M
Original Assignee
TRENKAMP M
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by TRENKAMP M filed Critical TRENKAMP M
Publication of GB1601444A publication Critical patent/GB1601444A/en
Expired legal-status Critical Current

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Classifications

    • 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
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F9/00—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium
    • F16F9/003—Dampers characterised by having pressure absorbing means other than gas, e.g. sponge rubber
    • 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
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F1/00—Springs
    • F16F1/36—Springs made of rubber or other material having high internal friction, e.g. thermoplastic elastomers
    • F16F1/37—Springs made of rubber or other material having high internal friction, e.g. thermoplastic elastomers of foam-like material, i.e. microcellular material, e.g. sponge rubber
    • 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
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F9/00—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium
    • F16F9/06—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium using both gas and liquid
    • F16F9/08—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium using both gas and liquid where gas is in a chamber with a flexible wall

Description

(54) IMPROVEMENTS IN SPRING DEVICES SUITABLE FOR VEHICLE AXLES (71) We, MARIA TRENKAMP and KONRAD GEHLE trading as TRENK AMP & GEHLE, a West German Offene Handelsgesellschaft of Marschendorfer StraBe, 2843 Dinklage (Oldb.), Federal Republic of Germany, do hereby declare the invention for which we pray that a patent may be granted to us and the method by which it is to be performed to be particularly described in and by the following statement: This invention relates to a spring device, particularly, although not exclusively, for vehicle axles.
In a known spring device for this purpose, a hollow spherical chamber of variable volume is divided by an inner resilient diaphragm into an upper and a lower half. A gas fills the upper half of the sphere and is separated and hermetically sealed off, by the diaphragm, from an incompressible hydraulic medium filling the lower half of the sphere. A piston movable with the vehicle wheel acts upon the hydraulic medium to urge the diaphragm upwards to compress the gas until pressure equalization is achieved at both sides of the diaphragm, whereupon the device becomes fully deflected.
In this hydropneumatic suspension device, the volume of gas is directly dependent on the size of the sphere so that different spring rates can only be achieved by using different sizes of sphere or by shifting the location of the inner diaphragm. In addition, the diaphragm is subjected to heavy stresses, in operation of the device, liable to cause a break down in the hermetic seal and to give rise to disturbances.
The present invention provides a spring device suitable for vehicle axles comprising a closed, resilient chamber of variable volume filled with a substantially incompressible fluid medium and a plurality of random, mobile, wholly self-contained, readily compressible filling components contained in the incompressible medium.
With this construction, the sealing problem is eliminated. Because the readily compressible filling components are wholly selfcontained, a different number of them is easily provided, contained in the substantially incompressible fluid medium in order to achieve different spring rates without the device having otherwise to be altered in any way. Thus not only can a spring device with a widely variable spring rate be readily produced, but also the spring rate can be readily altered subsequently by the user without appreciable expense, simply by removing some of the readily compressible filling components or by adding more of the readily compressible filling components.
A spring device according to the present invention, when used in a hydropneumatic suspension, has its incompressible medium acted upon by a pressure member movable with the vehicle wheel, as a result of which the readily compressible filling components are compressed equally on all sides by the pressure of the substantially incompressible fluid medium, in accordance with Pascal's Law, so that its volume is reduced bringing about the required spring action. The deflection of the device is terminated when the limit of compressibility of the readily compressible filling components or each such component is reached.
Each readily compressible filling component may have a solid cross-section and be formed from closed-pore foam material.
Suitable microcellular synthetic foams, for example, polyurethane foams, may be considered as such closed-pore foam materials which generally have a dense, closedpore superficial skin. Alternatively however, the readily compressible filling components may be composed of cellular rubber, particularly expanded rubber or other closed-pore foam elastomeric material.
Depending on the pressure range of the incompressible medium, it may also be advisable to construct the readily compressible filling components from an outer cover of resilient deformable material which is impermeable to liquid, the outer cover enclosing a core. Such an outer cover may be of a stronger material than the core, such as a core of foamed plastics material, and impermeable to fluids to prevent in particular the incompressible medium from penetrating into the core, even at high working pressures of the incompressible medium, for example, in the range from 10 to 30 atmospheres. This prevents the spring characteristics of the device from being adversely affected. The outer cover may consist of elastomeric material such as rubber or a rubber-elastic plastics material and it may possibly be fabric-reinforced, for example, in the manner of brake-line hoses for motor vehicles or pressure hoses.
It is further possible to form the readily compressible filling components as hollow members having an air or gas filling as a core instead of a core of foamed plastics material. In this case, each hollow member may consist simply of the outer cover referred to above.
The readily compressible filling components may be rod-shaped. A plurality of these rod-shaped components of a combined length corresponding to the required spring rate of the suspension device, may be introduced into the chamber of variable volume which is filled with the substantially incompressible fluid medium either then or after it has been mounted on the vehicle. In those cases where such rod-shaped compressible filling components are surrounded by an outer cover or formed by an air-filled or gas-filled hollow member, the outer cover or hollow member, after being cut to the desired length, being tightly sealed at the ends, for example, by vulcanizing or welding.
It is further possible to construct each readily compressible filling component in the form of a closed ring. One or more of these rings, possibly of different crosssection and different diameter, may be incorporated in a device of the present invention in order to achieve a required spring rate.
Finally, each compressible filling component may have the shape of a sphere, of a spheroid or other similar solid of revolution.
Specific embodiments of the present invention will now be described by way of example, and not by way of limitation, with reference to the accompanying drawings in which: Figures I and 2 each show an example of an embodiment of a suspension device in accordance with the present invention, in axial section, the suspension device being illustrated in the unloaded state in the right-hand half of the Figure and in the loaded or sprung-in state in the left-hand half of the Figure, in each case.
With reference to the accompanying drawings, the suspension devices illustrated diagrammatically in the drawings are used for vehicle axles, particularly of lorries or towed or coupled trailers, the suspension of the particular axle being formed in known manner by leaf springs or parabolic springs which, at their left-hand end in Figures 1 and 2, are supported for sliding in bearing blocks of the chassis or are articulated on a bracket at the chassis side and are secured at their other end on a supporting plate 1 of the present suspension device designated as a whole by 2 or 2'.
The suspension device 2 or 2' comprises a container which is formed by a resiliently deformable bellows 3 and which is filled with hydraulic medium in the form of a mixture of water and antifreeze. The bellows 3 is secured at its lower end on a holding ring 4 of the supporting plate 1 and at its upper end it is secured to a holding ring 5 which can form a part of the chassis frame designated in general by 6. In addition, the bellows 3 is embraced in its central region by a central holding ring 7. The bellows 3 forms a chamber 8 of variable volume which can be connected, in a manner known per se to a connection or compensating pipe 9 leading to a similar suspension device 2 or 2' (not shown). The further suspension device 2 or 2' may be associated with a further vehicle axle and both suspension devices 2, 2' may, for example, be disposed at the same side of the vehicle. As likewise known per se, two further suspension devices 2, 2' may, in this case, be associated with the two axles at the other side of the vehicle.
In the example of embodiment shown in Figure 1, a plurality of small compressible mobile members are contained in the chamber 8, which members float freely and occupy the volume of the chamber jointly with the hydraulic medium. According to the illustration in Figure 1, right-hand half, the floating members 10 have the shape of spheroids which, for the purpose of illustration, are shown in the upper third of the chamber 8 in elevation, in the lower third in cross-section and in the centre third in a smaller size. The floating members 10 are formed by a hollow member or outer cover 11 with an air filling 12 as a core. The floating members 10 have a maximum diameter which is smaller than the smallest cross-section of the connecting line 9 so that, under pressure loading or during the springing in, the floating members 10 can travel through the compensating line 9 and enter the further suspension device 2 connected at the other end. The spring rate of the suspension device 2 can be varied by the number of floating members 10, their size and their degree of compressibility. The left-hand half of Figure 1 shows the floating members in the compressed state.
In the examPle of embodiment shown in Figure 2 as distinct from the example of embodiment shown in Figure 1, mobile floating members 13 each in the form of a closed ring are provided, of which two are shown with different cross-sections and different diameters for illustration purposes.
The floating member 13 of smaller crosssection and smaller diameter, illustrated in the lower end region of the chamber 8, comprises a hollow member or outer cover 14 of rubber or rubber-elastic plastics material and an air-filling or gas-filling 15 as a core. The floating member 13 of larger cross-section and larger diameter, illustrated in the upper third of the chamber 8 in Figure 2, comprises a fabric-reinforced outer cover 16 and a core 17 of cellular rubber, particularly expanded rubber.
The spring rate can be varied over a wide range of sizes by using different crosssections and diameters and by using different constructions of floating members and also by using floating members of different compressibility and different numbers of the floating members 13, in the suspension device 2' as in the case of the suspension device 2 of Figure 1.
For this purpose, the bellows 3 is simply filled with the appropriate floating members 10 or 13 in the prescribed number, after which the bellows is secured to the holding rings 4 and 5 and its chamber 8 is filled with the hydraulic medium. A subsequent alteration of the spring rate by the user is also possible at any time by removing or adding floating members, after letting out the hydraulic medium and removing the bellows 3, which can be effected without appreciable expenditure on mounting.
In Figures 1 and 2, the pressure acting on the hydraulic medium through the supporting plate 1 during the springing in of the floating members is symbolized by the arrow 18. In the left-hand half of Figures 1 and 2, the floating members 10 or 13 are illustrated in the fully compressed state so that further springing in of these members is not possible and merely a transmission of force or pressure through the incompressible hydraulic medium contained in the chamber 8 takes place and only the spring action afforded by the leaf springs is still present, as is the case, for example, under full load conditions. Under such conditions, a linear spring characteristic is achieved by the leaf springs, while under empty load conditions or in the lower load range of the vehicle, for example, a lorry trailer, a desired progressively steepening spring characteristic is achieved due to the compressibility of the floating members.
Where floating members are required to travel through the compensating pipe 9 between interconnected spring devices, the floating members are not necessarily spheroidal in shape but may be rod-shaped or closed ring-shaped provided that they have a maximum dimension which is smaller than the smallest internal cross-section of the hydraulic fluid conduit 9 interconnecting the devices.
WHAT WE CLAIM IS: 1. A spring device suitable for vehicle axles comprising a closed, resilient chamber of variable volume filled with a substantially incompressible fluid medium and a plurality of mobile wholly self-contained, readily compressible filling components contained in the incompressible medium.
2. A device as claimed in claim 1 in which one at least of the compressible filling components has a solid cross-section and is formed of closed-pore foam material.
3. A device as claimed in claim 1 or 2 in which one at least of the compressible filling components consists of cellular rubber, expanded rubber or other closed-pore elastomeric material.
4. A device as claimed in any preceding claim in which one at least of the compressible filling components has an outer cover of resiliently deformable material which is impervious to fluids and a core enclosed by the outer cover.
5. A device as claimed in claim 4 in which the outer cover comprises elastomeric material or a rubber-elastic plastics material.
6. A device as claimed in claim 4 or 5 in which the outer cover is fabric-reinforced.
7. A device as claimed in claim 4, 5 or 6 in which one at least of the compressible filling components has a gaseous core, the component being hollow.
8. A device as claimed in any preceding claim in which the compressible filling components are rod-shaped.
9. A device as claimed in any preceding claim 1 to 7 in which the compressible filling component has the shape of a closed ring.
10. A device as claimed in any preceding claim 1 to 7 in which the compressible filling component has the shape of a sphere, a spheroid or a similar solid of revolution.
11. A device as claimed in any preceding claim having its variable volume chamber hydraulically interconnected with the variable volume chamber of a further device as claimed in any preceding claim.
12. A pair of devices as claimed in claim 11 in which the compressible filling components have a maximum dimension which is
**WARNING** end of DESC field may overlap start of CLMS **.

Claims (14)

**WARNING** start of CLMS field may overlap end of DESC **. enter the further suspension device 2 connected at the other end. The spring rate of the suspension device 2 can be varied by the number of floating members 10, their size and their degree of compressibility. The left-hand half of Figure 1 shows the floating members in the compressed state. In the examPle of embodiment shown in Figure 2 as distinct from the example of embodiment shown in Figure 1, mobile floating members 13 each in the form of a closed ring are provided, of which two are shown with different cross-sections and different diameters for illustration purposes. The floating member 13 of smaller crosssection and smaller diameter, illustrated in the lower end region of the chamber 8, comprises a hollow member or outer cover 14 of rubber or rubber-elastic plastics material and an air-filling or gas-filling 15 as a core. The floating member 13 of larger cross-section and larger diameter, illustrated in the upper third of the chamber 8 in Figure 2, comprises a fabric-reinforced outer cover 16 and a core 17 of cellular rubber, particularly expanded rubber. The spring rate can be varied over a wide range of sizes by using different crosssections and diameters and by using different constructions of floating members and also by using floating members of different compressibility and different numbers of the floating members 13, in the suspension device 2' as in the case of the suspension device 2 of Figure 1. For this purpose, the bellows 3 is simply filled with the appropriate floating members 10 or 13 in the prescribed number, after which the bellows is secured to the holding rings 4 and 5 and its chamber 8 is filled with the hydraulic medium. A subsequent alteration of the spring rate by the user is also possible at any time by removing or adding floating members, after letting out the hydraulic medium and removing the bellows 3, which can be effected without appreciable expenditure on mounting. In Figures 1 and 2, the pressure acting on the hydraulic medium through the supporting plate 1 during the springing in of the floating members is symbolized by the arrow 18. In the left-hand half of Figures 1 and 2, the floating members 10 or 13 are illustrated in the fully compressed state so that further springing in of these members is not possible and merely a transmission of force or pressure through the incompressible hydraulic medium contained in the chamber 8 takes place and only the spring action afforded by the leaf springs is still present, as is the case, for example, under full load conditions. Under such conditions, a linear spring characteristic is achieved by the leaf springs, while under empty load conditions or in the lower load range of the vehicle, for example, a lorry trailer, a desired progressively steepening spring characteristic is achieved due to the compressibility of the floating members. Where floating members are required to travel through the compensating pipe 9 between interconnected spring devices, the floating members are not necessarily spheroidal in shape but may be rod-shaped or closed ring-shaped provided that they have a maximum dimension which is smaller than the smallest internal cross-section of the hydraulic fluid conduit 9 interconnecting the devices. WHAT WE CLAIM IS:
1. A spring device suitable for vehicle axles comprising a closed, resilient chamber of variable volume filled with a substantially incompressible fluid medium and a plurality of mobile wholly self-contained, readily compressible filling components contained in the incompressible medium.
2. A device as claimed in claim 1 in which one at least of the compressible filling components has a solid cross-section and is formed of closed-pore foam material.
3. A device as claimed in claim 1 or 2 in which one at least of the compressible filling components consists of cellular rubber, expanded rubber or other closed-pore elastomeric material.
4. A device as claimed in any preceding claim in which one at least of the compressible filling components has an outer cover of resiliently deformable material which is impervious to fluids and a core enclosed by the outer cover.
5. A device as claimed in claim 4 in which the outer cover comprises elastomeric material or a rubber-elastic plastics material.
6. A device as claimed in claim 4 or 5 in which the outer cover is fabric-reinforced.
7. A device as claimed in claim 4, 5 or 6 in which one at least of the compressible filling components has a gaseous core, the component being hollow.
8. A device as claimed in any preceding claim in which the compressible filling components are rod-shaped.
9. A device as claimed in any preceding claim 1 to 7 in which the compressible filling component has the shape of a closed ring.
10. A device as claimed in any preceding claim 1 to 7 in which the compressible filling component has the shape of a sphere, a spheroid or a similar solid of revolution.
11. A device as claimed in any preceding claim having its variable volume chamber hydraulically interconnected with the variable volume chamber of a further device as claimed in any preceding claim.
12. A pair of devices as claimed in claim 11 in which the compressible filling components have a maximum dimension which is
smaller than the smallest internal crosssection of the hydraulic fluid conduit interconnecting the devices.
13. A spring device substantially as hereinbefore described with reference to the accompanying drawings.
14. A vehicle axle suspension system including spring devices as claimed in any preceding claim.
GB10221/78A 1977-03-22 1978-03-15 Spring devices suitable for vehicle axles Expired GB1601444A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19772712428 DE2712428A1 (en) 1977-03-22 1977-03-22 SPRING DEVICE, IN PARTICULAR FOR VEHICLE AXLES

Publications (1)

Publication Number Publication Date
GB1601444A true GB1601444A (en) 1981-10-28

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Family Applications (1)

Application Number Title Priority Date Filing Date
GB10221/78A Expired GB1601444A (en) 1977-03-22 1978-03-15 Spring devices suitable for vehicle axles

Country Status (8)

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AT (1) AT371577B (en)
BE (1) BE865037A (en)
DE (2) DE7708844U1 (en)
DK (1) DK124278A (en)
FR (1) FR2384996A1 (en)
GB (1) GB1601444A (en)
NL (1) NL7802154A (en)
SE (1) SE7803147L (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2534997A1 (en) * 1982-10-25 1984-04-27 Imp Clevite Inc FLEXIBLE WALL ELASTIC SHOCK ABSORBER
FR2534998A1 (en) * 1982-10-25 1984-04-27 Imp Clevite Inc DRY VISCOUS ELASTIC SHOCK ABSORBER
US4555098A (en) * 1983-11-25 1985-11-26 Imperial Clevite Inc. Self-stabilizing dry viscous spring damper
US4560150A (en) * 1983-11-25 1985-12-24 Imperial Clevite Inc. Dry viscous spring strut
US4577842A (en) * 1983-11-25 1986-03-25 Imperial Clevite Inc. Self-stabilizing dry viscous spring damper

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4460168A (en) * 1982-07-19 1984-07-17 Deere & Company Resilient mount for supporting a cab structure on the chassis of a vehicle
FR2576935A1 (en) * 1985-02-01 1986-08-08 Hutchinson Hydro-elastic and/or laminated fender
NL9401417A (en) * 1994-08-31 1996-04-01 Hendrik Lenten Pneumatic hydraulic shock and vibration damper.
GB2324352B (en) * 1996-01-05 1999-10-20 William Alexander Courtney Device incorporating elastic fluids and viscous damping
AU1204897A (en) * 1996-01-05 1997-08-01 William Alexander Courtney Device incorporating elastic fluids and viscous damping
DE102010043753B4 (en) * 2010-11-11 2012-11-08 Zf Friedrichshafen Ag Bellows spring with progressive spring characteristic
DE102011122219B4 (en) * 2011-12-23 2021-03-11 Grass Gmbh Damping device for a movable furniture part

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2534997A1 (en) * 1982-10-25 1984-04-27 Imp Clevite Inc FLEXIBLE WALL ELASTIC SHOCK ABSORBER
FR2534998A1 (en) * 1982-10-25 1984-04-27 Imp Clevite Inc DRY VISCOUS ELASTIC SHOCK ABSORBER
GB2129089A (en) * 1982-10-25 1984-05-10 Imp Clevite Inc Combined spring and damper using elastomeric particles as fluid
GB2129088A (en) * 1982-10-25 1984-05-10 Imp Clevite Inc Flexible wall spring/damper using elastomeric particles as medium
US4504044A (en) * 1982-10-25 1985-03-12 Imperial Clevite Inc. Dry viscous spring damper
US4509730A (en) * 1982-10-25 1985-04-09 Imperial Clevite Inc. Flexible wall spring damper
US4555098A (en) * 1983-11-25 1985-11-26 Imperial Clevite Inc. Self-stabilizing dry viscous spring damper
US4560150A (en) * 1983-11-25 1985-12-24 Imperial Clevite Inc. Dry viscous spring strut
US4577842A (en) * 1983-11-25 1986-03-25 Imperial Clevite Inc. Self-stabilizing dry viscous spring damper

Also Published As

Publication number Publication date
FR2384996A1 (en) 1978-10-20
AT371577B (en) 1983-07-11
DE2712428A1 (en) 1978-09-28
DE7708844U1 (en) 1981-12-10
SE7803147L (en) 1978-09-23
ATA190578A (en) 1982-11-15
DK124278A (en) 1978-09-23
BE865037A (en) 1978-07-17
NL7802154A (en) 1978-09-26
FR2384996B3 (en) 1980-11-07

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