Spring devices – Vehicle – Mechanical spring and nonresilient retarder
Patent
1986-10-15
1988-11-22
Reger, Duane A.
Spring devices
Vehicle
Mechanical spring and nonresilient retarder
18832214, 267 6415, 267127, F16F 500
Patent
active
047860375
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
The present invention relates to an arrangement for a spring suspension system which contains a load-absorbing or a mass-supporting mechanical main spring and a unit consisting of inner and outer cylinders. In such arrangement a piston and/or a piston rod, for the purpose of providing a damping function, works in an incompressible fluid, for example hydraulic oil, inside a working space, and with its corresponding area, via the fluid, works against the effect of a spring function produced by the main spring with the help of a moving device capable of being actuated through its first side by the main spring and capable of being actuated through its second side by the incompressible medium.
The application of maintaining the incompressible fluid during the return stroke of the piston is known in art. In the case of shock absorbers, for example, the arrangement of a gas cushion (gas spring) has been disclosed which is separated from the incompressible fluid with the help of a floating piston, one side of which is acted upon by the fluid, and the other side of which is acted upon by the gas cushion. The compression ensures that no gas is released within the fluid, which in turn provides the necessary conditions for sound function.
Also previously disclosed in relation to spring suspension systems for motor vehicles is the use of a moving device or a device which is capable of longitudinal displacement, the respective sides of which are acted upon by the main spring and by the incompressible medium. The main spring contributes to, or produces the compression of the fluid.
SUMMARY OF THE PRESENT INVENTION
The present invention is intended for use, amongst other things, in front fork assemblies in which the piston speed is high, for example 10 m/sec. The use of gas springs as compression springs for the operating fluid is problematical in such case because the piston rod is required to operate through sealing devices which at the same time separate the gaseous and liquid media. Sealing devices of this kind wear rapidly, imposing an unacceptable requirement for frequent service intervals for the system as a whole. Furthermore, the assembly as a whole is technically complex. The use of a moving device or a device which is capable of longitudinal displacement as described above is not obvious, since what is involved is the ability to avoid inappropriate changes in the damping characteristic because the piston speed may be higher during compression than during the return stroke.
The present invention provides for solution of above problems by use of a moving device, the possibility is afforded of getting to grips with the wear problem. At the same time very good damping characteristics can be achieved in front fork assemblies and similar assemblies with high piston speeds.
According to the present invention piston rod is provided with a bearing which, on return strokes of the piston, will permit the fluid to pass from the working space for the piston or the piston rod to a space under atmospheric pressure on the first side of the moving device, with the moving device containing a one-way valve which permits filling of the fluid from the space under atmospheric pressure to a space belonging to the working space beneath the piston whenever the return strokes of the pressure give rise to a tendency for low pressure to occur in the last-mentioned space.
In one preferred embodiment the device consists of an annular unit so arranged as to be capable of longitudinal displacement on the cylinder containing the piston, the cylinder being provided for this purpose with one or more openings via which the fluid is connected to this annualar unit. The unit may be regarded as constituting a movable support for the main spring, which attempts to force the unit towards an initial position or towards a position in which it is counterbalanced by the fluid pressure. A helical spring with normal spring characteristics can be used as the main spring, which in this case will function as a progressive return
REFERENCES:
patent: 3476354 (1969-11-01), Stubblefield
LandOfFree
Arrangement for a spring suspension system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Arrangement for a spring suspension system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Arrangement for a spring suspension system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-430765