Mechanical device having two modes of displacement

Details Mechanical device having two modes of displacement Mechanical device having two modes of displacement

1999-02-01

2002-04-02

Butler, Douglas C. (Department: 3613)

Brakes

Internal-resistance motion retarder

Combined with surface-friction brake

C188S136000, C267S205000

Reexamination Certificate

active

06364074

ABSTRACT:

The present invention relates to the field of mechanical systems for controlling displacement. For example a device of the invention can be used to control rapidly accelerated displacement that could give rise to an operational problem or to a safety problem.
More particularly, but in non-limiting manner, the device can be used in high-impulse projectile launchers that need to have two different dynamic behaviors in damping.
BACKGROUND OF THE INVENTION
The invention is particularly, but not exclusively, applicable to friction dampers of the type described in document FR 2 697 881. A damper device of that type comprises a fixed portion, a moving portion, and friction means interposed between the fixed portion and the moving portion.
OBJECTS AND SUMMARY OF THE INVENTION
The object of the invention is to improve the dynamic behavior in damping. This object is achieved by a mechanical device that has two modes of relative displacement between one assembly and another, with the transition between the two modes being controlled and determined by the time profile of the relative displacement.
More precisely, the object of the invention is to propose a mechanical device making it possible to manage response to external stress as a function of the amplitude of the impulse generated:
if the external stress generates low impulse (below a pre-established threshold), then the system should remain in a first relative displacement mode, i.e. it should move freely;
if the external stress generates a high impulse (greater than a pre-established threshold), then the system must change over to a second relative displacement mode, i.e. with damping or blocking.
In the context of the present invention, this object is achieved by a mechanical device for controlling changeover between two modes of relative displacement between two objects comprising:
two assemblies capable of moving in guided relative translation, one assembly being said to be fixed, and the other being said to be moving,
the device further comprising:
resilient control means interposed between the two assemblies with a controlled clearance to define the mode of relative displacement; and
an inertial mass associated with one of the assemblies and adapted to act selectively on the control means as a function of the time profile of moving assembly displacement in order to modify the clearance and the mode of relative displacement.


REFERENCES:
patent: 2459537 (1949-01-01), Oberstadt
patent: 2539275 (1951-01-01), Sahlin et al.
patent: 3783738 (1974-01-01), Pelat
patent: 5655632 (1997-08-01), Valembois
patent: 548536 (1956-06-01), None
patent: 2240943 (1974-02-01), None
patent: 0407755 (1991-01-01), None
patent: 1122015 (1956-08-01), None
patent: 2697881 (1994-05-01), None
patent: 2333165 (1997-06-01), None
patent: XP-002080223 (1981-09-01), None
NASA: “Improved Coulomb-Friction Damper” No. 12, part F, 12/85 p. 1424.

Affiliated with

Also associated with

Rating

Mechanical device having two modes of displacement does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Mechanical device having two modes of displacement, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mechanical device having two modes of displacement will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2847865