This invention relates to packaging materials, and more particularly to a cushion design, packaging in which the cushion design is used, and methods by which products are protected against damage otherwise possibly occurring due to shock loads (i.e. during distribution).
In developing a package for product protection, some fundamental information about the product is needed. To protect the product from shock, a fragility level must be determined. Fragility is the maximum acceleration and velocity change the product can withstand before damage occurs. This information is charted to form a damage boundary curve. Ideally the fragility level is determined experimentally through a test procedure such as American Society for Testing Materials (ASTM) D 3332 “Test Method for Mechanical-Shock Fragility of Products, Using Shock Machines.” Fragility is usually expressed in units of “g's” (gravitational acceleration) and indicates the maximum acceleration the product can withstand without being damaged. Therefore, the more fragile a product is the lower its fragility level or g-factor. Ranges of a typical cushioning system include very delicate (25-40 g's), delicate (40-60 g's), and moderately delicate (60-85 g's)
Once the shock fragility is known for the product, a cushioning material and package configuration that will provide the necessary protection can be developed. Historically, the use of cushion curves helps a designer identify a material, thickness and loading range based on a pre-determined drop height and required acceleration level.
Packaging material and packages capable of handling determined loads are here referred to as having fragility capability. As will be understood, one of the tasks facing a packaging designer is to provide fragility capability suitable for the product to be packaged and the loads which may be imposed during handling. Another of the tasks facing the designer is that of providing material which can be easily fabricated and easily handled by persons preparing products for shipment.
One conventional type of cushion design is known as an end cap. An end cap is used to cover or receive the end of a product being inserted into a box, and in use a pair are positioned between the ends of a (typically) elongated product and the enclosing box. One use of end caps is in packaging notebook computers and computer components such as hard disk drives.
With the foregoing in mind, it is one purpose of this invention to provide an end cap which imparts fragility capability and which derives favorable characteristics by combining several cushioning effects. In particular, the end cap of this invention achieves cushioning by combining the effects of material compression, deformation of an arch, an expansion of contact area as cushioning occurs.
Some of the purposes of the invention having been stated, others will appear as the description proceeds, when taken in connection with the accompanying drawings, in which:
While the present invention will be described more fully hereinafter with reference to the accompanying drawings, in which a preferred embodiment of the present invention is shown, it is to be understood at the outset of the description which follows that persons of skill in the appropriate arts may modify the invention here described while still achieving the favorable results of the invention. Accordingly, the description which follows is to be understood as being a broad, teaching disclosure directed to persons of skill in the appropriate arts, and not as limiting upon the present invention.
Before proceeding with discussion of the characteristics of end caps and packaging in accordance with this invention, it will be helpful to establish some terminology related to the illustrations to be described. A product with which end caps are used typically has a pair of such caps mounted on opposite ends of the product. Here, the end of an end cap which faces an opposing end cap is referred to as the “inside” end. The end which faces away from the product is referred to as the “outside” end. As the product is inserted into a box, typically by inserting the product into an opened one of the larger sides of a rectilinear enclosure, the side of the end cap which becomes proximal to the bottom of the box is referred to as the “bottom” side. The opposite side of the end cap is referred to as the “top” side. Finally, the remaining sides of the end cap are here referred to as the left and right sides.
Persons familiar with end caps will readily understand that such caps are conventionally made in a single configuration, which is then used at opposite ends of a product being packaged and oriented appropriately for such use. Further, end caps are also used where products are inserted into boxes through an opened one of the smaller sides of a rectilinear enclosure. Therefore the terminology introduced here is to be understood as being solely an aid in understanding some of the configurations to be described, and not as limiting on the invention. The physical characteristics of the invention to be described here are what is significant, as distinguished from the terminology used in an effort to assure understanding.
As will become clear from the discussion which follows, an end cap protects a product with which it is engaged from potential damage which may otherwise occur from loads imposed (or resolved) along three orthogonal axes. Using the orienting terminology set out above, those orthogonal axes are directed end to end of the product, up and down, and left and right. The loads imposed may be borne by crushing or deformation of the material of the end cap. In accordance with this invention, the loads are also borne by the spring effect of an arched portion of the end cap material and by a resulting enlargement of the area of contact between the end cap and the enclosing box.
With this discussion as background,
The body of material which forms the end cap device may be cast or molded from an appropriate foam or other material or may be fabricated by assembling parts to form the unitary body. It is contemplated for this invention that the end caps here described will enable a reduction in the quantity of material needed to form the end cap and also enable a reduction in the size of packaging for components packaged with this end cap as a consequence of the use of three characteristics to bear loads possibly imposed—material crush, arch spring, and arch expansion of contact area with an enclosing box.
Another type of end cap in accordance with this invention is shown in
This invention contemplates a third type of end cap device, shown in
As applied, end cap bodies 50 in accordance with this invention are shown in
The present invention contemplates that the techniques here disclosed are amenable to practice of packaging methods. More particularly, one method which implements this invention involves mounting a pair of end cap bodies as here taught on opposite ends of a fragile product and inserting the bodies and product into an enclosing box as shown in
As practiced, this method includes forming an end cap body as a unitary body of cushioning packaging material defining a product receiving and supporting recess, mounting a pair of the end cap bodies on opposite ends of a fragile product, and inserting the product and the end cap bodies into an enclosing box. As here taught, the body defines a pair of arched portions disposed on opposite sides of the recess and defining a central axis transverse to the recess, each of the arched portions having a curved inner surface spaced from and concave toward the recess and an outer surface lying generally parallel to the inner surface and defining an outer boundary for the body, and an outer surface defining a contact surface for an enclosing box. The end caps achieve a fragility capability by combined effects of the crush characteristics of the material, the deformation characteristics of the arched portions, and the enlargement of the contact surface upon deformation of the arched portions;
In the drawings and specifications there has been set forth a preferred embodiment of the invention and, although specific terms are used, the description thus given uses terminology in a generic and descriptive sense only and not for purposes of limitation.