Brakes – Internal-resistance motion retarder – Using a rotary-type fluid damper
Patent
1984-10-04
1987-06-23
Kashnikov, Andrews
Brakes
Internal-resistance motion retarder
Using a rotary-type fluid damper
188306, 188307, 280700, F16D 5700, F16F 914, B60G 1506
Patent
active
046746080
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to hydraulic dampers for use, in one example, in suspension systems of heavy vehicles. More particularly, the invention relates to hydraulic dampers of rotary form which have the important advantages over conventional linear dampers of ruggedness and compactness.
2. Description of the Background Art
It is one problem with existing dampers that the damping characteristic varies with changes in operating conditions and in particular with changes in temperature. One object of this invention is to provide an improved hydraulic damper in which variations with temperature of the damping characteristic is much reduced.
Accordingly, the present invention consists in one aspect in a rotary hydraulic damper comprising a rotor mounted within a stator so as to define therewith at least one working chamber filled in use with hydraulic fluid; a vane for each working chamber provided on the rotor and arranged to sweep through said chamber on rotation of the rotor; and means provided in each vane to permit restricted flow of hydraulic fluid past said vane, the means comprising at least one orifice permitting turbulent flow through the vane together with valve means operating to allow increased flow when a predetermined pressure threshold is exceeded in the damper wherein each vane is provided at its radial extremity with an axially directed recess, there being located in said recess two rigid seal elements and spring means disposed between said seal elements to urge the seal elements in opposite axial directions.
The restricted flow through the orifice is capable of theoretical calculation which assists in design optimisation of the damping characteristic. Since the flow through the orifice is turbulent, it is dependent to a relatively small extent on changes in temperature so that the damping characteristic remains substantially constant over a working temperature range. The performance of the damper can therefore be close to optimum at all times.
It is generally desirable that a rotary damper should be of the smallest size consistent with the desired damping performance. This is particularly the case in the application of vehicle suspension systems where the space available on the vehicle for the damper is restricted by the design considerations of other elements of the suspension. In one particular example of a suspension system having parallel torsion bar springs extending transversely of the vehicle to support wheel arms at opposite ends, it is desirable that the radial spacing between the torsion bar springs should be minimised.
SUMMARY AND OBJECTS OF THE INVENTION
It is an object of a further form of this invention to provide an improved hydraulic damper in which overall dimensions can be reduced without detracting from the damping performance.
Accordingly, the present invention consists in a further aspect in a rotary hydraulic damper comprising a stator having two stator abutments directed radially inwardly of a generally cylindrical stator cavity; a rotor mounted coaxially within said cavity with surfaces slidably engaging said stator abutments to define two circumferentially spaced working chambers filled in use with hydraulic fluid the rotor being hollow to accommodate one torsion bar spring of a torsion bar spring pair; vanes provided on the rotor to sweep through respective working chambers on rotation of the rotor and means in each vane permitting restricted flow of hydraulic fluid past the vane, wherein one of the stator abutments is recessed partly to accommodate the other torsion bar spring of the pair.
In most applications, it is important that there should not be unbalanced forces on the rotor of a hydraulic damper. If a rotor is provided with two rotor vanes moving in separate working chambers, very careful matching of the two working chambers will be necessary to avoid unbalanced forces. It is an object of a further aspect of this invention to provide an improved hydraulic damper in which unbalanced forces on the rotor a
REFERENCES:
patent: 1426115 (1922-08-01), Shultz
patent: 1521602 (1925-01-01), Derimon
patent: 1920273 (1933-08-01), Peo
patent: 2054466 (1936-09-01), Peo
patent: 2314493 (1943-03-01), Guy
patent: 2419651 (1947-04-01), Magrum
Dowling Steven
Morris Roy
Horstman Defence Systems Limited
Kashnikov Andrews
Oberleitner Robert
LandOfFree
Hydraulic damper does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Hydraulic damper, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hydraulic damper will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-715762