Technical Field

This invention relates to the field of isolators and, in particular, to a light weight, low profile isolator for sensitive electronic equipment which provides superior shock and vibration protection.

Background

Isolators for protecting a mounted structure from shock or vibration forces exerted by another structure are well known and have been used in many industrial and military applications. One class of isolators uses arched flexural elements arranged in a bar-shaped pattern to provide different spring characteristic responses to shock and vibration forces along longitudinal and transverse directions, as shown in U.S. Patent Nos. 4,190,227 and 4,783,038, or in a circular shaped pattern to provide a spring characteristic response alleged to be more uniform and move independent of the direction of origin of the shock and vibration forces, as shown in U.S. Patent No. 5,149,066. It has been found, however, that when the latter isolation is coupled to the corners of a frame supporting sensitive electronic elements inadequate shock and vibration isolation is obtained in a severe environment and excessive installation space is required. Thus, it is a primary object of the present invention to provide an improved shock and vibration isolator.

It is another object of the present invention to provide an improved shock and vibration isolator which can protect sensitive electron packages in very severe elements.

It is a further object of the present invention to provide an improved shock and vibration isolator which requires a minimum of installation space.

It is still another object of the present invention to provide an improved shock and vibration isolator which is extremely light weight.

Disclosure of Invention

A shock and vibration isolator for isolating one or more sensitive elements from a support structure is provided in which frame means having a plurality of corners supports such elements and a plurality of isolator means are coupled to the frame means at the corners and to the support structure, the isolator means including a plurality of arched, individual, flexural support elements configured in an arc opening into the corners. In a particular embodiment, the support elements are configured in a semicircle and the isolator means are grouped into opposing pairs. A damping cushion is contained within and extends from the isolator means to provide additional shock isolation for the frame means. In a second embodiment, the support elements are coupled directly to the sensitive element and the support structure at preselected locations and are configured in an arc opening generally towards the center of gravity of the element.

The novel features which are believed to be

characteristic of the invention, together with further objects and advantages thereof, will be better understood from the following description in connection with the accompanying drawings in which the presently preferred embodiments of the invention are illustrated by way of example. It is to be understood, however, that the drawings are for purposes of illustration and description only and are not intended as a definition of the limits of the invention.

Brief Description of the Drawings

Figure 1 is an isometric view of the present invention.

Figure 2 is a detailed view of the isolator of the present invention.

Figure 3 is a partial isometric view of a second embodiment of the present invention.

Best Mode for Carrying Out the Invention

Referring now to Figure 1, a frame 10 is shown having a plurality of vertical sides 12 and a plurality of horizontal members 14. The frame 10 has mounted therein, shown in phantom, a sensitive electronic package 16, such as a CD-ROM, which it is desired to isolate from shock and vibration forces. Positioned in each corner 18 of the frame 10 is an isolator 20 having an arc-shaped base 22 mounted by screws 24 to a support structure 26, an elevated support 28 mounted by screws 30 to one of the horizontal members 14 and a plurality of arched, individual, flexural support elements 32 coupled to the arc-shaped base 22 and the elevated support

28, as shown in greater detail in Figure 2. The support elements 32 may be coupled to the base 22 and the support 26 as described in U.S. Patent No. 4,149,066, incorporated herein by reference, and act as tensioned springs flexing in response to the transmission of shock and vibration forces between the support structure 26 and the frame 10, as described in the above-referenced patent. The support elements 32 are generally formed from a plurality of stainless steel wires wound to form a stranded rope, while the base 22 and the elevated support are generally formed from aluminum.

As shown in the Figures, each arc-shaped base 22 and its corresponding support elements 32, which are shown having a semicircular configuration, is positioned so that the open portion 34 faces into a corner 18 of the frame 10 and is faced by an opposing base 22 and corresponding support elements 32 facing into an opposing corner 18. This arrangement has several distinct advantages over the use of the above-cited circular isolator. First, it allows the corners of the frame 10 to be open so that electronic packages carefully occupy the frame 10 and not interfere with any of the support elements 32. Second, while the opposing isolators 20 can face one another and act in concert to provide a more uniform spring response independent of direction of origin of the shock and vibration forces, each isolator 20 can be rotated with respect to one another to fine tune the entire structure to random shock and vibration forces or to best tune the entire structure from forces

originating in particular directions. In this regard, the arcuate shape of the base 22 can also be selectively configured, instead of being merely hemispherical, as can the number and placement of the support elements 32. The open nature of the arc-shaped base 22 also permits the containment therein and the extension therefrom of a clamping cushion 36 to isolate the elevated support 28 and the sides 12 if the shock forces cause the frame 10 to bottom out despite the spring action of the support elements 32 of the isolator 20. The damping cushion 36 may be made from a high density cellular urethane, such as provided by E.A.R specialty composites, a division of Cabot Safety Corporation, Indianapolis, Indiana.

Referring now to Figure 3, a second embodiment of the invention is illustrated. In this embodiment, isolator 20 is shown positioned between the sensitive electronic package 16 and the support structure 24 and consists of a plurality of arched, individual flexural support elements 22' coupled directly, as by welding, to the package 16 and the support structure 24 and arranged in an arc-shaped configuration 38 with the open portion 40 of the configuration 38 facing generally toward the center of gravity (C.G.) of the package 16. The number and position of the isolators 20' on the package 16 can be varied depending upon the size and configuration of the package 16 and the direction of the shock and vibration forces, as can the precise shape of the arc-shaped configuration 38, the number and placement of the support elements 22' thereon, and the general orientation of

the open portion 40 toward the center of gravity. As previously stated, a damping cushion 36' may be placed within the arc-shaped configuration and extending therefrom to afford further shock damping if the shock forces cause the package 16 and the support structure to bottom out despite the spring action of the support elements 22' of the isolators 20' .

While the invention has been described with reference to particular embodiments, it should be understood that the embodiments are merely illustrative as there are numerous variations and modifications which may be made by those skilled in the art. Thus, the invention is to be construed as being limited only by the spirit and scope of the appended claims.

Industrial Applicability

The invention has applicability to the shock absorber industry.