The damping means also resists said external forces and performs the further function of damping the natural oscilla- tion of the air spring. Without the damping means, the natural oscillation of the air spring is undamped. Without the air spring, the damping means cannot restore the top and bottom plates to their respective positions of repose.
In a second embodiment of the invention, a seat bottom construction eliminates the air spring of the first embodiment so that the top plate and bottom plate may be spaced closer to one another when a shock is applied to the platform. If the plates can come closer together, a greater amount of shock is absorbed.
In the second embodiment, the bias means includes at least one spring having a shape something like a conventional leaf spring but with an arch formed mid-length thereof. In a first variation of the second embodiment, the at least one arched leaf spring has opposite ends secured to the top plate and the at least one arched leaf spring is connected at its mid-point to the bottom plate.
Alternatively, the at least one arched leaf spring has oppo- site ends secured to the bottom plate and the at least one arched leaf spring is connected at its mid-point to said top plate.
Any number of such arched leaf springs may be employed. In another variation of the second embodiment, the bias means includes at least one set of opposed arched leaf springs. A first arched leaf spring of the set of opposed arched leaf springs has a mid-point secured to the bottom plate and a second arched leaf spring of the set of opposed leaf springs has a mid-point secured to the top plate. The first and second arched leaf springs have respective opposite ends secured to
one another.
In still another variation of the second embodiment, the bias means includes at least one set of opposed arched leaf springs where a first arched leaf spring of said set of opposed arched leaf springs has opposite ends secured to the bottom arched leaf springs has opposite ends secured to the top plate. The first arched leaf spring has a mid-point secured to a mid-point of the second arched spring.
The damper means of the first embodiment is employed in the second embodiment to damp the oscillations of the arched leaf spring or springs.
The second embodiment also employs a simpler set of brackets than the “U”-shaped brackets of the first embodi- ment. The brackets of the second embodiment are essentially flat. Each flat bracket is apertured to receive an axle upon which is secured an apertured end of a truncate link, the apertured end of an elongate link, or the collar of a damper. The axle and hence the link or collar is retained by a suitable cotter pin, a “C”-clip, or the like.
An important advantage of the first embodiment of this invention is that it provides a platform that has an adjustable air spring shock absorber and an adjustable shock absorber damper that has an infinite number of self-adjusting damping rates due to internal valving provided by a damper piston that is slideably mounted in the damper main body.
Another advantageous feature is that the novel platform is made of a small number of readily available, inexpensive parts.
Still another advantage is the provision of a platform that may be directly supported by a boat deck or other vehicle surface, in the absence of pedestals, so that it may be stood upon.
A closely related advantage is the provision of a platform that is sized to fit within the confines of a bolster chair so that a user can simultaneously gain the benefits of a bolster chair and the shock absorbing platform when the seat part of the bolster chair is folded into a storage position.
Still another advantage is the provision of a platform upon which a user can sit upon in a boat or other vehicle lacking a shock absorbing seat.
Additional advantages are derived from the ability of the structure to have as few as only two scissors-like elongate links, only one damper and only one air spring.