CONTAINER SECUREMENT DEVICE WITH VISUAL INDICATOR

BACKGROUND OF THE INVENTION PRIOR HISTORY

This application claims the benefit of pending U.S. Patent Application No. 11/372,670, filed in the United States Patent and Trademark Office on March 10, 2006, and pending U.S. Patent Application No. 11/451,282, filed in the United States Patent and Trademark Office on June 12, 2006.

FIELD OF THE INVENTION

The present invention relates to container securement devices and more particularly to improvements in cargo container securement devices providing automatic securement and release of a cargo container with a visual indicator for indicating whether the device is a container securing configuration or a container releasing configuration.

DISCUSSION OF PRIOR ART

Containerized lading has become immensely popular due to advantages such as labor savings resulting from decreased cargo handling. Modular or standardized containers may be shipped from point to point using a variety of different carriers

including rail cars, trucks and ships. Such cargo containers are conventionally provided with corner castings including locking openings used in securing the containers to the various types of vehicles upon which they are loaded.

One type of container securement device used in the past is a container pedestal including a base portion upon which a corner of the container rests, as well as vertically extending walls within which a corner of the container is captured. A latch pivotable about a horizontal axis engages a locking opening in a vertical wall of the container for holding the container down against the base while permitting automatic entry and release of the container. One example of such a container pedestal is disclosed in U.S. Patent No. 4,382,734.

Another securement device used in the past with cargo containers is a twistlock. This device includes a base upon which the container may rest together with a shear block engageable with a locking opening in the bottom, horizontal wall of the container corner casting. A locking head is manually moved from a released position in alignment with the shear block to a locked position in which the container cannot be lifted away from the base. The head is rotated manually between the locked and the unlocked positions, and automatic entry and release of the container is not possible.

The primary use of container pedestals has been on rail cars where containers are typically loaded and unloaded with a crane and automatic entry and release are important. On the other hand, twistlocks have primarily been used to secure containers to trucks where their small size and light weight is an advantage.

United States Patent No. 4626,155 ('155 Patent), which issued to Hlinsky, et al., discloses an automatic container securement device with a spring biased, cam surfaced

head. The '155 Patent teaches a device for automatically securing a cargo container to a support such as a deck of a vehicle or a second container with which the first container is to be stacked. The device includes a base having a projecting shear block received in the locking opening of the container. A head rotates between an unlocked or loading position in which the head moves through the locking opening and a locked position in which the container is secured. Automatic entry and release are provided by a spring within the base biasing the head to the locked position but permitting movement to the unlocked position when torque is applied by engagement of the container with a cam surface on the head. Visible indication of the locked position and positive locking of the head in the locked position may be provided. For stacked containers, two aligned shear blocks and two angularly offset heads are provided and the spring may be released for manual locking of the device to one container followed by automatic locking to the second container.

It will be seen from a further review of the above-referenced patents and other prior art generally known to exist that the prior art does not teach an automatic twist lock device comprising a uniquely configured shaft member for receiving springs of varying types, which various springs may be interchanged with one another depending on the requirements of the target location. Further, it will be seen that the prior art does not teach the use of spiral torsional springs constructed from tempered steel for effecting substantially uniform spring performance across a wide range of temperatures. The prior art thus perceives a need for an automatic twist lock device comprising a uniquely configured shaft member for receiving and actuating springs of varying types, which various springs may be interchanged with one another depending on the requirements of the target location.

Moreover, the prior art perceives a need for an automatic twist lock incorporating a spiral torsional spring constructed from tempered steel for effecting substantially uniform spring performance across a wide range of temperatures.

SUMMARY OF THE INVENTION

Accordingly, among the objects of the present invention are to provide a cargo securement device providing the advantages of both a pedestal latch and a twistlock; to provide a device achieving automatic cargo container entry and release without the size, weight and expense of container pedestals; to provide cargo securement devices useful for securing a container directly to a support surface of a vehicle; to provide a container cargo securement device providing automatic entry and release without projecting horizontally beyond the container; to provide a cargo securement device having interchangeable, temperature dependent actuating elements; and to provide a cargo securement device overcoming disadvantages of those used in the past. In brief, the above and other objects and advantages of the present invention are achieved by providing a cargo container securement device for securing a cargo container to a support surface. The support surface may be associated with a vehicle such as a rail car, truck or ship. A cargo container securement device in accordance with the invention includes a housing or base adapted to be fixed to the support surface. A shaft is rotatable around an axis extendable through the housing and a cam outer head surface is carried by the shaft and is adapted to move through the cargo container locking opening. The head has a

shape permitting it to move through the locking opening when the cam head is in a first rotational position. When the head is in a second angularly offset position, it cannot move through the opening and serves to secure the container against the housing or base. A spring is connected between the shaft and the housing to resiliently bias the head to the second position while permitting rotation to the first position in response to the application of torque. Upper and lower surfaces of head are engageable with the locking opening to apply torque to the head as the head moves through the locking opening of the cargo container.

The present invention thus provides a container securement assembly for securing a container to a support, which container has a lock-actuating opening, and which lock- actuating opening has opposing head-engaging portions. The container securement assembly comprises a base, a shaft, a head, and a select torsional spring element. The base is adapted to be secured to the support and comprises a spring-receiving cavity and spring end-fixing means. The shaft is supported by the base and is thereby rotatable about an axis of rotation extendable through the lock-actuating opening. The shaft comprises a head-receiving end and a transversely noncircular spring-receiving end.

The spring-receiving end extends into the spring-receiving cavity and comprises certain spring-actuable end-receiving structure such as an aperture or groove extending transversely through the spring-receiving end. The head is carried by the head-receiving end and is adapted to rotate through the lock-actuating opening under forceful contact with the head-engaging portions. The head comprises an upper locking surface and a lower unlocking surface, which differ in their locking/unlocking dynamic(s).

The selected torsional spring element is received in the spring-receiving cavity and comprises a central shaft interface for interfacing with the end-receiving structure. The torsional spring element is thereby made actuable intermediate the spring-receiving end and the spring end-fixing means by container-provided forces as the head-engaging portions contact the head. The head-engaging portions thus apply torque to the shaft via the head, the head being movable through the lock-actuating opening when in an actuated, unlocked, rotational head position and immovable through the lock-actuating opening when in a relaxed, locked rotational head position. The locked rotational head position functions to prevent movement of the head through the lock-actuating opening for enabling the user to selectively secure the container to the support.

Certain visual-indicating means or a combination visual indicator - release mechanism provides visual indication of spring element actuation and enables the user to release or unfix one end of the spring element for enabling manual rotation of the same, in the event, for example, of head twist failure. The visual indicating means are manually operable to enable manual spring element rotation and thus further enable manual rotation of the head intermediate the unlocked, rotational head position and the locked, rotational head position. The visual indicating means may preferably be spring biased for translating a portion of the visual indicating means from a spring-actuated first position to a spring-relaxed second position when the spring element. The base may preferably comprise certain mechanical stop structure such as an integrally formed internal boss and the spring element may comprise certain base- engaging structure such as a tabbed extended arm. The base-engaging structure of the spring element is mechanically stoppable via the mechanical stop structure of the base for

preventing rotation of the spring element in a first direction. The spring element may thus be mechanically stopped intermediate the mechanical stop structure and the visual indicating means or is rotatable intermediate base-based mechanical stop structure and indicator-based mechanical stop structure for preventing the spring element from rotating past the unlocked and locked rotational head positions.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features of my invention will become more evident from a consideration of the following brief description of patent drawings:

Figure No. 1 is a top plan view of a state of the art container securement device showing a container locking head in a relaxed, locked rotational head position.

Figure No. 2 is a side plan view of the container securement device otherwise shown in Figure No. 1.

Figure No. 3 is a top plan view of an improved container securement device according to the present invention showing a container locking head in a relaxed, locked rotational head position with a combination visual indicator - release mechanism indicating that the device is ready for conventional operation of the device via container- provided forces.

Figure No. 4 is a side plan view of the container securement device otherwise shown in Figure No. 3.

Figure No. 5 is a top plan view of the improved container securement device according to the present invention depicting (1) the visual indicator - release mechanism

in a position for releasing the device so as to enable manual rotation of the head and (2) a direction of rotational movement.

Figure No. 6 is a side plan view of the container securement device otherwise shown in Figure No. 5.

Figure No. 7 is a top plan view of the improved container securement device according to the present invention depicting (1) the visual indicator - release mechanism in a position for releasing the device so as to enable manual rotation of the head and (2) the head rotated manually so as to align the head with the shear block of the base housing.

Figure No. 8 is a side plan view of the container securement device otherwise shown in Figure No. 7.

Figure No. 9 is a longitudinal cross-sectional type depiction of a corrosion resistant sleeve for interfacing intermediate the base housing and the combination visual indicator - release mechanism.

Figure No. 10 is an end view type depiction of the corrosion resistant sleeve otherwise depicted in Figure No. 9.

Figure No. 11 is a first end view of a pin element of the combination visual indicator - release mechanism.

Figure No. 12 is a side plan view of the pin element otherwise depicted in Figure No. 11.

Figure No. 13 is a second end view of the pin element otherwise depicted in Figure Nos. 11 and 12.

Figure No. 14 is a first side view of a release knob of the combination visual indicator - release mechanism.

Figure No. 15 is a second side view of the release knob otherwise depicted in Figure No. 14, which second side view is 90 rotational degrees from the first side view.

Figure No. 16 is an end view of the release knob otherwise depicted in Figure Nos. 14 and 15.

Figure No. 17 is a side view of a compression coil type spring element of the combination visual indicator - release mechanism.

Figure No. 18 is a cross sectional bottom view depiction of a state of the art base housing with a first phantom through hole for receiving a spring setting pin or fastener.

Figure No. 19 is a cross sectional side view depiction of the base housing otherwise depicted in Figure No. 18.

Figure No. 20 is a cross sectional bottom view depiction of an improved base housing according to the present invention with (1) a second phantom through hole, which second phantom through hole has a greater diameter relative to the first through hole otherwise depicted in Figure No. 18 for receiving the combination visual indicator - release mechanism, and (2) an integral internal boss.

Figure No. 21 is a cross sectional side view depiction of the improved base housing otherwise depicted in Figure No. 20.

Figure No. 22 is a cross sectional side view depiction of the improved base housing illustrated with the corrosion resistant sleeve installed.

Figure No. 23 is an exploded side view type depiction of the combination visual indicator - release mechanism showing a fragmentary section of the base housing with sleeve installed and compression coil type spring element disposed intermediate the release knob and pin element.

Figure No. 24 is a side view depiction of the assembled combination visual indicator - release mechanism in a spring locking first position for enabling conventional operation of the device via container-provided forces.

Figure No. 25 is a side view depiction of the assembled combination visual indicator - release mechanism in a spring releasing second position for enabling operation of the device via manually provided forces.

Figure No. 26 is a bottom plan type depiction of a state of the art torsional spiral spring element with phantom through hole for receiving a spring setting pin or fastener.

Figure No. 27 is a cross sectional bottom plan type depiction of a state of the art base housing with spring setting pin or fastener installed through the through hole of the base housing.

Figure No. 28 is a bottom plan type depiction of an improved torsional spiral spring element according to the present invention outfitted with a tabbed, extended arm end and a through hole for receiving a first end of the spring setting pin element of the combination visual indicator - release mechanism.

Figure No. 29 is a cross sectional bottom plan type depiction of an improved bas housing and combination visual indicator - release mechanism in an assembled state.

Figure No. 30 is a bottom view depiction of a state of the art base housing with state of the art torsional spiral spring element received therein and set via a spring setting pin or fastener received through the through holes of the housing and spring element.

Figure No. 31 is a bottom view depiction of the improved base housing outfitted with improved torsional spiral spring element according to the present invention showing a combination visual indicator - release mechanism in a spring setting first position for enabling conventional operation of the device via container provided forces.

Figure No. 32 is a bottom view depiction of the improved base housing and torsional spiral spring element showing the combination visual indicator - release mechanism in a spring releasing second position and torsional spring element being rotated in a first, undesired direction, which movement is prevented via the integral, internal boss and tabbed, extended arm.

Figure No. 33 is a bottom view depiction of the improved base housing and torsional spiral spring element showing the combination visual indicator - release mechanism in a spring releasing second position and torsional spring element being rotated in a second, desired direction, which movement is limited via the first end of the pin element and the tabbed, extended arm.

Figure No. 34 is a fragmentary perspective view of a support surface and a number of cargo containers to be supported by container securement devices of the present invention

Figure No. 35 is a fragmentary, bottom perspective view of a container outfitted with a head-actuating opening.

Figure No. 36 is an enlarged side plan view of the device otherwise depicted in Figure No. 2.

Figure No. 37 is an enlarged side view of a container securement device with certain parts broken away to show otherwise hidden internal structure.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawings, the preferred embodiment of the present invention concerns a container securement device or assembly 24 for securing an ISO type container 22 to a support structure 20 such as a carrier deck, which carrier deck is designed to haul ISO type containers through all types of environmental conditions, including often highly variable temperature conditions. Two ISO type containers 22 are illustrated and referenced in juxtaposed, end-to-end relation in superior adjacency to a support structure 20 in Figure No. 34. Notably, the International Organization for Standardization (ISO) is an international standard-setting body composed of representatives from national standards bodies. The organization produces world- wide industrial and commercial standards, the so-called ISO standards. A standardized ISO type container (also known as an isotainer) can be loaded on support structures 20 of container ships, railroad cars, and trucks. There are five common standard lengths of an ISO container, namely, 20 ft (6.1 m), 40 ft (12.2 m), 45 ft (13.7 m), 48 ft (14.6 m) and 53 ft (16.2 m). US domestic standard containers are generally 48 ft and 53 ft. Container capacity (of ships, ports, etc) is measured in twenty-foot equivalent units (TEU, or sometimes teu). A twenty-foot equivalent unit is a measure of containerized cargo capacity equal to one standard 20 ft (length) x 8 ft (width) x 8.5 ft (height) container. In metric units this is 6.10 m (length) x 2.44 m (width) x 2.59 m (height), or approximately 39 m ³ . Most containers today are of the 40-ft variety and thus are 2 TEU. Forty-five ft containers are also designated 2 TEU. Two TEU are referred to as one forty-foot equivalent unit (FEU). These two terms of

measurement are used interchangeably. So-called "high cube" containers have a height of 9.5 ft (2.9 m), while half-height containers, used for heavy loads, have a height of 4.25 ft (1.3 m).

Of critical structural importance to the present invention is the fact that standard ISO type containers comprise a lock-actuating opening as generally illustrated and referenced at 32 in Figure No. 35. From an inspection of Figure No. 34, it will be seen that each of the eight corners of each container 22 comprises a corner casting 28 having an upwardly or downwardly facing horizontal wall 30 in which is formed the noncircular lock-actuating opening 32. The lock-actuating openings 32 are engageable by the securement devices 24 to achieve securement and automatic entry and release of the containers 22.

As will be seen from an inspection of Figure No. 35, the lock-actuating opening 32 is of a generally elongated or rectangular shape having a major axis generally parallel to the longest dimension of the container 22. Each lock-actuating opening 32 is defined by a perimeter including two relatively long side walls or head-engaging portions 34, which head-engaging portions 34 are joined by two somewhat rounded relatively short end walls 36. The head-engaging portions 34 and the end walls 36 of the lock-actuating openings 32 extend between the external and internal surfaces of the horizontal wall 30 of a corner casting 28. In order to effect securement of a container 22, the lock-actuating openings 32 should preferably comprise substantially parallel, opposing head-engaging portions 34.

In Figure No. 35, it will be seen that there is illustrated in somewhat schematic form a support structure 20 upon which cargo containers 22 are to be secured by

securement devices 24 constructed in accordance with the principles of the present invention. Support structure 20 may, for example, be the deck or floor of a rail car or other transport vehicle. When each container 22 is lowered onto support structure 20, the securement devices 24 automatically secure the containers 22 in place. The principles of the present invention are applicable to devices for securing various types of containers to various types of supports. In the illustrated embodiments of the invention, the containers 22 are of a standard and modular type.

As earlier noted, the present specification claims the benefit of earlier filed patent applications in the United States Patent and Trademark Office, namely U.S. Patent Application No. 11/372,670, filed in the United States Patent and Trademark Office on March 10, 2006, as well as U.S. Patent Application No. 11/451,282, filed in the United States Patent and Trademark Office on June 12, 2006. The specifications thereof may be considered hereby incorporated by reference thereto insofar as certain common matter between the devices of the earlier filed applications extends to the subject matter contained in this specification.

The securement device 24 according to the present invention is illustrated in Figure Nos. 3 - 8. The prior or state of the art devices 124 are generally depicted in Figure Nos. 1, 2, and 36 for clarity of comparison. Securement device 24 preferably comprises a base or housing 42, and a head 44. It is contemplated that head 44 is substantially identical to the specified heads of the earlier filed applications and thus rotatable between a locked rotational head position and an unlocked rotational head positions to effect selective securement or release of a cargo container 22. Figure Nos. 3 - 6 generally depict the head 44 in a relaxed, locked rotational head position.

In the illustrated arrangement, each securement device 24 is adapted to be attached or secured to the support structure 20 by welding or fastening the base 42 to the support structure 20. Preferably, one securement device 24 is positioned in alignment with each of the four lower corner castings 28 of a container 22 as generally depicted in Figure No. 35.

Base 42 preferably comprises upper and lower housing portions, and certain spring end-fixing means. The spring end- fixing means may preferably be defined by a combination visual indicator - release mechanism 70 and an indicator-receiving tunnel or through-hole 56, which receiving tunnel or hole 56 is formed in lower housing portion as generally depicted in Figure Nos. 20 and 21. It may be seen from a comparative inspection of Figure Nos. 18 and 19 versus Figure Nos. 20 and 21 that the state of the art through-holes 156 are generally smaller in diameter than through holes 56. Though the diameter of holes 56 is not necessarily of critical importance to the essence of the invention, it is here being noted that the through holes 56 are of somewhat different design as compared to through holes 156 so as to allow for receipt of alternative, improved structure.

The upper and lower housing portions and are preferably secured together by suitable fasteners such as bolt down mechanisms and/or assemblies. For example, certain bolts 10, and certain cooperative bolt-locking nuts 11 are illustrated and referenced in Figure Nos. 2, 4, and 36. The upper and lower housing portions preferably define an internal spring-receiving chamber or cavity 58 as generally depicted and referenced in Figure Nos. 20 - 23, 29, and 31 - 33. From a comparative inspection of the noted figures versus Figure Nos. 18, 19, 27, and 30, it may be seen that the cavity 58 essentially differs

from the state of the art cavities 158 in that cavity 58 comprises an integrally formed, internal boss as at 59. The internal boss 59 functions as a torsion spring stop to prevent the twist head 44 from rotating in an/the undesired direction.

Notably, upper housing portion preferably comprises a projecting shear block or base 60. It is contemplated that shear block 60 preferably comprises a shape similar to, but slightly smaller than, the lock-actuating opening 32. With the container 22 secured in the locked position, the shear block 60 is received in lock-actuating opening 32 to prevent movement of container 22 in any horizontal direction. In other words, the base 42 comprises a shear block 60 having a shape that is cooperable with the lock-actuating opening 32. Thereby, the shear block 60 may be received in the lock-actuating opening 32 when the container 22 is secured for preventing lateral container movement relative to the base 42. It is thus contemplated that the shear block 60 effectively functions to enhance container securement.

A shaft 62 is journalled for rotation in an opening defined at the center of shear block 60 as illustrated in phantom and referenced in Figure No. 37. Shaft 62 is believed substantially identical to the state of the art shaft(s) for receiving torsional spiral springs as set forth in the earlier filed applications to which this specification claims a benefit, and thus shaft 62 comprises a head-receiving end and a spring-receiving end. The spring- receiving end extends into the spring-receiving cavity 58. Head 44 is received by the head-receiving end and is preferably attached thereto by means of a groove pin (as at 64 in Figure No. 37) or key so that shaft 62 and head 44 may rotate as a unit. Within chamber 58, shaft 62 includes an enlarged hub portion. A select spring element, as may be preferably defined by a torsional spiral type spring element 46 is connected between

the hub 66 and the base 42 in order to resiliently hold the shaft 62 and head 44 in the locked rotational head position. It should be noted that spring-receiving end or hub 66 may comprises a chamfered spring-actuable transverse cross-section and/or a spring- actuable groove. In accordance with features of the present invention, the securement device 24 preferably comprises a select spring element 46 for biasing or actuating the head 44 to the locked rotational head position. The select spring element 46 is received in the spring- receiving cavity 58 and actuable intermediate the spring-receiving end or hub 66 and certain spring end-fixing means (as may be preferably defined by the combination visual indicator - release mechanism of the present invention).

In this last regard, it is contemplated that the spring element 46 may be selected based upon its particular suitability for locale-specific temperature ranges. In other words, it is noted that containers 22 are displaced from one locale to another and thus are exposed to differing climactic conditions depending on the origin, destination, and route conditions. Certain spring elements are better equipped to respond to actuating forces depending on the ambient temperature and properties inherent in the material used in the construction of the spring element. For example, it is contemplated that sturdier, materials such as steel, may be preferred for use in regions exposed to relatively more extreme weather conditions with wide-ranging temperatures primarily as a means to decrease the likelihood of element failure and to enhance the predictability of lock performance to operators in the field who load and unload containers 22 in varying environmental conditions.

Conversely, less sturdy materials such as rubber may be preferred for use in regions exposed to relatively temperate weather conditions with narrowly ranging temperatures. In any event, it is contemplated that locale-specific temperature ranges may be definable or groupable into two ranges, namely, a temperate (or narrow) range and an extreme (or broad) range, the temperate and extreme ranges being defined relative to one another. In other words, that which is not temperate is extreme and that which is not extreme is temperate. For example, a certain extreme type temperature range may include an origin exposed to temperatures exceeding 110° (or an upper limit at +130° Fahrenheit (~ +55° Celcius)) and a destination exposed to temperatures below 0° Fahrenheit (or a lower limit at -50° Fahrenheit (~ -45° Celcius) (notably, in this last regard, the Association of American Railroads (AAR) requires that container securement devices, such as securement device 24, satisfy certain performance load ranges for a temperature range of +130° F to -50° F).

If the foregoing scenario may describe an extreme temperature range, a temperature range of 40° Fahrenheit to 80° Fahrenheit could very well describe a temperate temperature range (i.e. a range falling within the extreme temperature range). The central notion being addressed is that differing spring elements may be used for differing temperature ranges, the differing spring element being actuable via a single, uniquely configured shaft member, such as shaft 62. Thus, while a metallic, or preferably steel, torsional spring may be specified for use in target locations typically having a wide fluctuation in temperatures (such as North America or Asia), an elastomeric, or rubber, torsional spring may be well suited for use in target locations typically having a more tempered or narrow fluctuation in temperatures (such as Ireland).

As a rule of thumb, non-strained elastomers typically have a coefficient of expansion ten times that of steel, a fact that has been considered in the choice of materials used in the construction of the selectable spring elements of the present invention, as well as the spring-receiving cavity 58. Certain rubber materials, for example, may have an average coefficient of linear expansion on the order of 80 x 10 ^'6 (°C) ^" ' while steel has an average coefficient of linear expansion on the order of 10 - 13 x 10 ^"6 ( ⁰ C) ^"1 . The behavior of rubber in response to temperature changes, however, is more complex than the foregoing would seem to suggest. Whereas most materials exhibit a positive coefficient of linear expansion, that of elastomers changes from positive to negative values with increasing strain. The process effecting a change in sign of the coefficient of expansion is given the term "thermoelastic inversion".

It is further noted that elastomeric torsional springs tend to become more brittle and/or resistant to deformation at relatively low temperatures (-3O ⁰ F - -40 ⁰ F) and thus often adversely affect the magnitude of entry and exit forces required to actuate the rotational movement of the head 44. When temperatures drop below 40° Fahrenheit, rubber springs require a marked increase in entry and/or exit force to effect rotational movement of head 44. Indeed, at temperatures approaching the lower limit of the AAR specifications, the required exit force may approach 4,000 pounds for a rubber spring element. Even if a rubber or elastomeric spring were to remain functional at this temperature, it is doubtful whether many lift systems could provide the necessary exit force(s) to successfully remove secured containers 22 from support structures 20.

Given the complexity of principles relating to thermoelastic inversion as applied to an elastomeric torsional spring experiencing temperature fluctuations, and the fact that

elastomeric torsional springs become more unpredictable in fluctuating temperatures, it is believed preferable to incorporate a metallic (or preferably steel) spiral spring into the securement device where practicable. Excellent results have been achieved utilizing certain annealed or tempered steel strips, such as 1090 annealed steel strip, but it is noted that certain alloyed steels have also been effective. Further, it is contemplated that certain stainless steels could be used when improved corrosion resistance is desired. Notably, the preferred steel is tempered to effect substantially uniform spring-actuating performance within a temperature range of +130° F to -50° F. In all cases, spring- receiving cavity 58 is formed to volumetrically accept the dynamic temperature- dependent nature of the selected spring element 46 and allow for thermal expansion and contraction (whether linear or volumetric) of the materials composing the selected spring element 46.

The select spring element 46 may thus be preferably defined by a spiral, torsional spring formed of relatively more predictable metallic material such as steel. At the inner periphery of the spiral, torsional spring is a central shaft interface or first spring end 67. It will be seen from an inspection of the noted figures that first spring end 67 is designed to mate with a groove formed in the hub 66. From a comparative inspection of Figure Nos. 26 and 28, it may be seen that first spring end 67 is substantially identical as compared to state of the art first spring ends 67 of the spring element. Opposite the first spring end 67 of spiral torsional spring is a second spring end 57. The second spring end is extended and tabbed for reasons discussed hereinafter. Adjacent the second spring end is certain structure for cooperating with the spring end-fixing means or combination visual indicator - release mechanism for preventing rotational movement of the second

spring end 57. The structure may be defined by a certain spring setting through hole 59 for accepting or receiving a first end of the visual indicator - release mechanism.

The select spring element 46 serves as a torsion spring biasing head 44 continually to its locked position. The spring force or spring constant is chosen to cooperate with the cam outer surface of head 44 to provide a desired entry and exit force encountered when the container 22 is lowered onto or lifted off of support structure 20. The spring force or constant may be varied by selection of the configuration and characteristics of materials of the spring body.

The head 44 and the cam outer surface is generally symmetrical about its axis of rotation and the axis of shaft 62. In the spring-relaxed, locked rotational head position, head 44 is not aligned with lock-actuating opening 32, and container 22 is secured in position because head 44 overlies portions of the corner casting horizontal wall 30. By interaction of the outer cam surface and the perimeter of the lock-actuating opening 32, the head 44 can be rotated (via spring-actuation) to an unlocked or loading rotational head position during the action of which the head 44 can move relative to the container 22 through the lock-actuating opening 32.

The outer cam surface preferably comprises an upper locking or loading surface 48A; and a lower unlocking or unloading surface 48B. The upper locking or loading surface 48A is directed generally away from base 42, and the lower unlocking or unloading surface 48B directed generally toward the base 42. The upper and lower surfaces 48 A and 48B are shaped to interact with the perimeter of the lock-actuating opening 32 as the head 44 moves into or out of the corner casting 28. Furthermore, the upper and lower surfaces 48A and 48B are shaped somewhat differently from one

another so that the force required for the head 44 to enter the lock-actuating opening 32 is smaller than the force required for the head 44 to exit from the lock-actuating opening 32. In this regard, it should be noted that the locking surface 48A is convexly shaped relative to the unlocking surface 48B for effecting a dynamically (or continually-changing) forced locking engagement and the unlocking surface comprises a substantially planar contact portion for effecting a substantially statically (or unchanging) forced unlocking engagement.

The select spring element 46, when in a relaxed, unactuated state, normally holds head 44 in the locked rotational head position as has been illustrated. In this position, the head 44 is angularly offset from the shear block 60 and cannot freely move through the lock-actuating opening 32. As a container 22 is lowered toward support structure 20, the perimeter of the lock-actuating opening 32 and specifically the head-engaging portions 34 engage the upper locking surface 48 A. As lowering of container 22 continues the reaction between the upper locking surface 48A and the lock-actuating opening 32 results in a torque applied around the axis of head 44 and shaft 62.

This torque results in deformation of the select spring element 46 as head 44 rotates from the relaxed, locked rotational head position toward the actuated, unlocked rotational head position. As head 44 reaches the loading position, it is able to move through lock-actuating opening 32 and beyond wall 30 into the corner casting 28. As head 44 clears wall 30, the select spring element 46 returns the head 44 to the relaxed, locked rotational head position so that the container 22 is thereafter secured in place. The variable entry force required to rotate head 44 during loading of container 22 onto support surface 20 may range from 100 up to about 800 pounds.

When container 22 is removed from support structure 20, a substantially larger force is required due to the configuration of the lower unlocking surface 48B. More specifically, as container 22 is lifted, the perimeter of lock-actuating opening 32 engages lower unlocking surface 48B. The resultant force applies a torque about the axis of shaft 62 deforming the select spring element 46 and permitting head 44 to rotate from the relaxed, locked rotational head position to the actuated, unlocked rotational head position.

Head 44 thereby moves out of corner casting 28 through the lock-actuating opening 32 and beyond wall 30. Thereafter, the select spring element 46 returns the head 44 to its locked rotational head position. The exit force required during lifting of container 22 from the support structure 20 may, for example, preferably ranges up to about 2,200 pounds. It will thus be seen that the locking surface 48A effects a variable entry force during insertion of the head 44 into the lock-actuating opening 32 and the unlocking surface 48B effects a substantially uniform exit force during removal of the head 44 from the lock-actuating opening 32, the ratio of the required exit force to the required entry force ranging from about 1 to 22.

It will thus be understood that the container securement system of the present invention preferably comprises a base 42; a shaft 62; a head 44; a (spiral type torsional) spring element 46, and certain visual-indicating means, as described in more detail hereinafter. The base 42 is adapted to be secured to a support 20. The shaft 62 is supported by the base 42 and rotatable about an axis of rotation extendable through the lock-actuating opening 32 of a container 22. The shaft comprises a head-receiving end and a spring-receiving end.

The head is carried by the head-receiving end of the shaft 62 and is adapted to rotate through the lock-actuating opening 32 under forceful contact with the head- engaging portions 34. The head comprises an upper locking surface as at 48A and a lower unlocking surface as at 48B. The locking surface 48 A is convexly shaped relative to the unlocking surface 48B for effecting a dynamically forced locking engagement. The unlocking surface 48B comprises a substantially planar contact portion for effecting a substantially statically forced unlocking engagement.

The spring element 46 comprises a central shaft interface as at 67 for interfacing with the spring-receiving end or hub 66 of the shaft 62. The spring element 46 is actuable via the spring-receiving end by container-provided forces as the head-engaging portions 34 contact the head 44. The head 44 is thereby movable through the lock- engaging opening 32 when in an actuated, unlocked, rotational head position and is immovable through the lock-engaging opening 32 when in a relaxed, locked rotational head position. The locked rotational head position thus prevents head movement through the lock-actuating opening 32 for selectively securing the container 22 to the support 20. The visual-indicating means essentially function to provide a visual indication of the spring element configuration and enable the user to manually release the spring from an actuated state if the head 44 becomes otherwise lodged and prevents unlocking movement of the container 22 from the support 20. The visual-indicating means as preferably defined by combination visual indicator - release mechanism 70 is generally depicted in Figure Nos. 3 - 8, 24, 25, 29, and 31 - 33. The mechanism 70 is cooperable with the spring element 46 and operable via spring element movement for providing a visual indication of spring element configuration.

In other words, when the spring element 46 is rotated so that the hole or structure 59 becomes frictionally disengaged from the pin 71 of the mechanism 70, the otherwise actuated compression coil type spring element 72 restores itself toward a relaxed state thereby displacing the pin 71 from a first pin position (as generally depicted in Figure Nos. 3, 4, 24, 29, and 31) to a second pin position (as generally depicted in Figure Nos. 5 - 8, 25, 32, and 33) for visually indicating when the device is ready for use or when the internal spring element 46 has been released so as to allow the manual rotation of the twist head 44.

Referencing Figure Nos. 9 - 17, it may be seen that the mechanism 70 preferably comprises a corrosion resistant sleeve 73, a pin 71, a knob/head 74, and a spring 72. The mechanism is assembled as generally depicted in Figure No. 23. Figure Nos. 3 and 4 show the mechanism 70 in the engaged position for normal or conventional use of the device for automatic engagement and removal of containers 22. Figure Nos. 5 and 6 illustrate the mechanism 70 pulled out or in the second pin position for enabling the twist head 44 to be manually rotated as at arrow 100. Figure Nos. 7 and 8 illustrate the mechanism 70 pulled out or in the second pin position with the head 44 manually rotated so as to align the head 44 with the shear block 60 of the housing 42.

To achieve these functions, the sleeve 73 is received in the through hole 56 and flush with the side of the housing 42 as comparatively depicted in Figure Nos. 21 and 22. The sleeve 73 may be secured in place by mechanical means or by way of a tack weld. The pin comprises first and second pin ends, which first pin end may oriented internally to the cavity 58 and which second pin end may receive the knob/head 74. The indicator

spring 72 is installed or received in radially inward adjacency to the sleeve 73 and the pin is installed or received in radially inward adjacency to the spring 72.

Figure No. 30 depicts a state of the art securement device in which the spring element 146 is fixed and cannot be released. Figure No. 31 depicts the improvement of the present invention with related spring setting components in a normal or conventional operating configuration. Figure No. 32 depicts the improved base housing 42 and torsional spiral spring element 46 showing the combination visual indicator - release mechanism 70 in a spring releasing second position and torsional spring element being rotated in a first, undesired direction, which movement is prevented via the integral, internal boss 59 and tabbed, extended arm 80. Figure No. 33 generally depicts the improved base housing 42 and torsional spiral spring element 46 showing the combination visual indicator - release mechanism 70 in a spring releasing second position and torsional spring element 46 being rotated in a second, desired direction, which movement is limited via the first end of the pin element 71 and the tabbed, extended arm 80.

While the above description contains much specificity, this specificity should not be construed as limitations on the scope of the invention, but rather as an exemplification of the invention. For example, as is described hereinabove, it is contemplated that the present invention essentially discloses a container securement device for securing a container to a support, the container having a lock-actuating opening, the lock-actuating opening comprising opposing head-engaging portions. The container securement device comprises a base, a shaft, a head, and a spring element. The base is adapted to be secured

to the support. The shaft is supported by the base and is rotatable about an axis of rotation extendable through the lock-actuating opening. The shaft comprises a head- receiving end and a spring-receiving end, the spring-receiving end comprising spring- actuable end-receiving structure. The head is carried by the head-receiving end and adapted to rotate through the lock-actuating opening under forceful contact with the head-engaging portions. The head comprises an upper locking surface and a lower unlocking surface, the locking surface being convexly shaped relative to the unlocking surface for effecting a dynamically forced locking engagement and the unlocking surface comprising a substantially planar contact portion for effecting a substantially statically forced unlocking engagement. The spring element 46 interfaces with the shaft 62 and is thereby actuable by container-provided forces as the lock-actuating opening 32 contacts the head 44. The head 44 is thereby movable through the lock-actuating opening 32 when in an actuated, unlocked, rotational head position and is immovable through the lock-actuating opening 32 when in a relaxed, locked rotational head position. The locked rotational head position prevents head movement through the lock-actuating opening 32 for selectively securing the container 22 to the support 20.

The visual-indicating means providing visual indication of spring element 46 actuation and enable the user to release or unfix one end of the spring element 46 for enabling manual rotation of the same, in the event, for example, of head twist failure. The visual indicating means are manually operable to enable manual spring element 46 rotation and thus further enable manual rotation of the head 44 intermediate the unlocked, rotational head position and the locked, rotational head position. The visual indicating

means may preferably be spring biased for translating a portion of the visual indicating means from a spring-actuated first position to a spring-relaxed second position when the spring element 46. The visual-indicating means may be preferably defined by the mechanism heretofore specified. The base 42 may preferably comprise certain mechanical stop structure such as the boss 59 and the spring element 46 may comprise certain base-engaging structure such as the tabbed extended arm 80. The base-engaging structure of the spring element 46 is mechanically stoppable via the mechanical stop structure of the base 42 for preventing rotation of the spring element in a first direction. The spring element 46 is thus mechanically stoppable intermediate the mechanical stop structure and the visual indicating means or is rotatable intermediate base-based mechanical stop structure (e.g. boss 59) and indicator-based mechanical stop structure (a first pin end of the pin 71) for preventing the spring element 46 from rotating past the unlocked and locked rotational head positions. Notably, from an inspection of Figure No. 37, it may be seen that the shaft 62 and the spring element 46 are internal to the device 24, and thus otherwise hidden from view. In other words, it is often difficult to ascertain the spring element actuation or configuration state from an external vantage point, and thus was conceived the visual- indicating means or means for providing a visual indicator of the configuration state of internal components.

The visual-indicating means, as heretofore preferably defined, essentially function to visually indicate the state of internal spring element actuation or configuration (and degree of shaft rotation) so that passersby may quickly ascertain whether a device 24 is in

a proper operative state. If, for example, the visual-indicating means indicate that the internal components are not properly configured or actuate, the passerby or technician may rotate the head 44 via some head-rotating means so that the shaft 62 and spring element 46 are more properly configured. The combination visual indicator-release mechanism 70, as heretofore described, is cooperable with the spring element 46 via through hole 56 for externally indicating the configuration state of internal components and for enabling the user to manually reconfigure the spring element 46 by enabling manual rotation of the head 44 intermediate the unlocked and locked rotational head positions.

Accordingly, although the invention has been described by reference to a preferred embodiment, it is not intended that the novel device be limited thereby, but that modifications thereof are intended to be included as falling within the broad scope and spirit of the foregoing disclosure, the following claims and the appended drawings.