Collapsible And Expandable Enclosure

Abstract

A collapsible and expandable enclosure is made of rigid panels. Two rectangular panels form the top and bottom. Other panels form side and end walls of sectional construction. The end walls are in two upper and lower rectangular sections which are hinged to each other on a horizontal axis and also to the end edges of the top and bottom. The side walls are in six sections, three upper and three lower. The center side wall sections are trapezoidal in shape and are hinged to the side edges of the top and bottom. The end side wall sections are in the shape of isosceles triangles and are hinged to adjacent end wall sections and also to adjacent center side wall sections. In the collapsed condition of the enclosure all the end and side wall sections are folded inwardly between the top and bottom. In the expanded condition the wall sections unfold outwardly, with the side wall sections being pulled outwardly automatically by their hinged connection with the end wall sections until the three upper and three lower side wall sections abut along a horizontal parting line.

Description

BACKGROUND OF THE INVENTION

1. Field Of The Invention

This invention relates to expandable and collapsible enclosures and, more particularly, to an improved enclosure especially useful as a shelter which combines hard wall construction with a low profile in the collapsed state. Although the invention will be disclosed with relation to mobile trailers of the so-called "camper" type, it will be realized that the invention is applicable to many other types of enclosures, especially other types of shelters.

2. Description Of The Prior Art

Collapsible and expandable shelters have been known to mankind since ancient times. Most often such shelters had a roof and walls of a flexible material such as cloth or animal hides. The problems generated by soft wall construction, such as high heat loss from the shelter's interior, limited privacy and protection against intruders, poor noise insulation characteristics, poor adaptability to glass window installations and poor adaptability to roof or wall mounted interior accouterments have caused the almost universal abandonment of soft wall shelters in favor of hard wall shelters for permanent residences.

Now a great number of people are attempting to escape to the blandishments of the countryside and forest without completely abandoning the comfort of the city. Some of these people find the soft wall tent which has been the mainstay of the camper to be inferior to hard wall constructions for the reasons set forth above. Yet, at least in the travel-trailer or camper class of recreational vehicles, the tent camper has traditionally offered advantages over hard wall constructions which usually had no collapsed state. For example, the tent camper in its collapsed state has a low center of gravity and a low profile for less resistance to both head and cross winds for improved towing stability and visibility, and for greater ease of road handling and parking due to compact dimensions. In order to combine the advantages of the tent camper with those of a hard wall construction, a certain type of camper has been developed having a hard roof and base sections but soft wall sections. In this camper, of course, the walls retain the disadvantages listed above for soft wall construction.

Other collapsible camper type structures have been devised in an effort to combine the advantages of hard wall construction and collapsibility. Prior structures of this nature, however, have certain disadvantages concerning deployment or conversion of the structure from its collapsed to its expanded state. In a first type of such a structure, the deployment operation requires basically as much manual work and operations as the soft-walled camper. Specifically, hard slide-out end wings are used in this type of construction to constitute horizontal flat bunk surfaces. In order to assure sufficient structural rigidity for these horizontal end wings, external braces are affixed as part of the development process. In conjunction with the end wings a number of side, roof and end panels are subsequently moved into position to effect the resultant fully-enclosed hard wall expanded configuration. The time required to perform the foregoing manual deployment operations is approximately the same as that required for the more conventional soft-walled tent camper. In addition, the slide-out end wings involve relatively complicated and expensive channels, tracks and/or guides to effect the slide-out operation. Finally, there are a number of mating edges or surfaces between the various side, roof and end panels. Butt-type, or overlapping panel-to-panel interfaces between the various surfaces are thus required and, as such, present certain design and mechanical complexities attendant with sealing and/or "weatherproofing" these joints or interfaces.

Other attempts to provide collapsible hard wall camper constructions involve "telescoping" and "in-folding wall" arrangements. These also generally require channels, guides, tracks, and/or the mechanical equivalent for the erection or deployment operation. In addition, these constructions also generally involve a number of edges which must be mated or sealed against one another to effect the closed, fully-expanded configuration. Such constructions do not, however, offer a very large ratio of fully-expanded volume to stowed volume as compared with the slide-out end wing type. For this latter type, such ratio can easily exceed two because of the extra volume realized by the deployable "wing" sections of the unit. The "telescoping" and "in-folding wall" units have a deployed volume of, at best, only twice that of the stowed volume.

SUMMARY OF THE INVENTION

The applicant's invention combines hard wall construction, high ratio expanded to collapsed volume, and ease of deployment in a single enclosure. This combination provides advantages heretofore not singularly available in the prior art.

Over known prior art arrangements which offer both hard-walled construction and low profile stowability, such as those described above, it is an object of the applicant's invention to offer greater ease of deployment due to the absence of slide-out mechanisms, telescoping members, and externally mounted end wing supports or braces.

Another object is to provide more simplicity of construction by the extensive use of an ultra-simple self-sealing hinge device in lieu of more complex sliding guides and telescoping members. This makes for less complicated panel-to-panel sealing or weatherproofing requirements and less complicated panel-to-panel mechanical interfaces.

Another object is to provide a unique over-the center arrangement of articulated hard wall panels to form an expandable and collapsible enclosure which is gravity retained or locked in expanded as well as in collapsed condition.

In summary, it is the object of the applicant's invention to permit incorporation of virtually all of the advantages of the prior art into one structural embodiment.

The applicant's invention accomplishes the above stated objects by a unique articulated arrangement of hard wall panels which can be transformed rapidly and easily from a collapsed (stowed) configuration into a fully-expanded (deployed) configuration.

The entire articulation arrangement requires no sliding or telescoping elements -- only a single folding of hinges between adjacent panels. The individual panels, being rigid elements, comprise the basic mechanical "links" of the articulation mechanism. The primary links in the mechanism are a base, two base end wall sections, a roof or top, and two roof end wall sections. The base and the two base end wall sections constitute an open three-bar linkage mechanism which is, in effect, a kinematic "mirror image" of the roof and its two roof end wall sections. Two hinge joints interconnect the respective base and roof end wall section to form a six-bar linkage. Side wall panels constitute secondary elements which are articulated in slave-fashion by motion of the respective end wall sections. The motion of these side wall panels has the reciprocal effect of restraining the opposing end wall sections to articulate in a "synchronous" or complementary type motion, as will be discussed in greater detail subsequently.

The six-bar linkage mechanism desirably is arranged to have an over-the-center position in expanded condition to provide a gravity lock to retain the enclosure in this condition.

The deployment of the panels may be manually accomplished if the size of the enclosure and the weight of the materials of construction so allow. Alternatively, the deployment may be accomplished by well known force-multiplying or power-actuated mechanisms.

BRIEF DESCRIPTION OF THE DRAWINGS

A preferred embodiment of the applicant's invention will now be described with reference to the drawings wherein:

FIG. 1 is a perspective view of a camper-trailer unit embodying this invention with the unit being shown in a fully-collapsed condition.

FIG. 2 is a view corresponding to FIG. 1 but showing the unit in a fully-expanded condition.

FIGS. 3 through 7 are side views of the unit shown in FIGS. 1 and 2 showing successive stages in a deployment sequence.

FIGS. 8 through 10 are fragmentary side views of enclosures embodying this invention showing various end configurations in the expanded condition.

FIG. 11 is a fragmentary perspective view of an end portion of an enclosure embodying this invention in its expanded condition and showing a torsion spring arrangement for facilitating movement between collapsed and expanded conditions.

FIG. 12 is a view corresponding to FIG. 11 but showing a tension coil spring arrangement.

FIG. 13 is a view corresponding to FIG. 11 but showing a power-operated linear actuator arrangement for moving the enclosure between collapsed and expanded conditions.

FIG. 14 is a fragmentary side view of an end portion of an enclosure embodying this invention in its expanded condition showing a modified configuration of the end wall sections.

FIG. 15 is a fragmentary plan view of the enclosure shown in FIG. 14.

FIG. 16 is a fragmentary vertical sectional view of the enclosure shown in FIG. 14.

FIG. 17 is a view corresponding to FIG. 16 but showing the enclosure in its collapsed condition.

FIG. 18 is an enlarged fragmentary sectional view taken substantially on line 18--18 of FIG. 14 to illustrate details of construction.

FIG. 19 is a somewhat diagrammatic elevational side view of an enclosure embodying this invention showing another spring arrangement for facilitating movement between collapsed and expanded conditions and another actuator arrangement for effecting such movement.

FIG. 20 is an enlarged fragmentary view of a portion of FIG. 19.

FIG. 21 is a fragmentary sectional view taken substantially on line 20--20 of FIG. 19.

FIG. 22 is a fragmentary view corresponding to a portion of FIG. 19 showing another spring arrangement.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to FIGS. 1 to 7 of the drawings there is shown a camper-trailer unit embodying this invention. The unit includes the usual base 20 having ground-engaging wheels 22 and a towbar 24 adapted to be attached to a towing vehicle (not shown). The base 20 is generally rectangular in plan view, has a floor (not shown), and preferably is provided with upstanding fixed end and side wall portions 26 and 28, respectively, so that it generally has a tray-like configuration. The unit has the usual roof or top 30 that is coextensive with the base 20, normally arranged parallel thereto, and is separable vertically upwardly from the base from the collapsed position, shown in FIG. 1, to the fully-deployed or expanded condition shown in FIG. 2. Both the base 20 and top 30 are of rigid or hard wall construction.

The unit also includes a pair of generally rectangular panel-like end wall sections 32 for the base 20, and generally rectangular panel-like end wall sections 34 for the top or roof 30. All of these wall sections 32 and 34 are of generally the same planar dimensions and are of rigid or hard wall construction. The base end wall sections 32 are hinged along generally parallel horizontal axes 36 to the upstanding fixed end wall portions 26 of the base 20, while the roof end wall sections 34 are similarly hinged about parallel horizontal axes 38 to the opposite ends of the roof 30. The two end wall sections 32 and 34 at each end of the unit are also hinged to each other along parallel horizontal axes 40. Thus, the base 20, top 30, and four end wall sections 32 and 34 form a six-bar linkage arrangement.

The arrangement is such that in the stowed or fully-collapsed condition of the unit, the end wall sections 32 and 34 are folded inwardly and are disposed between the base 20 and the top 30 and generally parallel thereto, as shown in FIG. 1. In this condition the fixed wall portions 26 and 28 of the base 20, together with its floor, provide a storage compartment in the base beneath the infolded wall sections 32 and 34. In the expanded condition of the unit, the end wall sections 32 and 34 associated with the base 20 and with the top 30 are extended at an angle of at least 90.degree. with respect thereto, as shown in FIG. 2. In this latter figure the base and top end wall sections 32 and 34 extend respectively at equal obtuse angles with respect to the base 20 and with respect to the top 30, but as will be described hereinafter, this angle may be of the order of 90.degree. or more. In the arrangement shown in FIGS. 2 to 7, the end wall sections 32 and 34 which are hinged together are at an angle of the order of 90.degree., when the unit is fully expanded but, again, this angle may vary from an acute angle to one which is of the order of 180.degree..

Associated with the base 20 are a pair of panel-like side wall main sections 42, one on each side of the unit. These sections 42 are hinged to the upper edges of the corresponding upstanding fixed side wall portions 28 for pivotal movement about longitudinal horizontal parallel axes 44. The top 30 is similarly provided with panel-like side wall main sections 46 which are hinged to the longitudinal side edges of the top for pivotal movement about longitudinal horizontal parallel axes 48. All the side wall main sections 42 and 46 are of hard wall construction, of essentially the same planar dimensions and are arranged for pivotal movement from a stowed or collapsed position wherein they are folded inwardly into a position generally parallel to and between the base 20 and top 30 of the unit to an expanded position at an angle of substantially 90.degree. to the base and top, as shown in FIG. 2. In this position the two side wall main sections 42 and 46 on each side of the unit are coplanar and have opposed edges 50 and 52, respectively, which are substantially abutting.

As will be seen from the showings of FIGS. 2 and 7, the side wall main sections 42 and 46 are generally trapezoidal in shape having longitudinal short and long parallel edges, with the long edge being hinged to the associated base 20 or top 30.

Associated with each side wall main section 42 and 46 are a pair of panel-like side wall end sections 54 of hard wall construction, all triangular in configuration and of the same planar dimensions. Each side wall end section 54 is in the shape of an isosceles triangle, as shown best in FIG. 7, having its base 56 hinged to the corresponding end edge of the associated side wall main section 42 or 46 for folding movement relative thereto. One of the other edges of the triangle, i.e., edge 58, is similarly hinged to the associated end wall section 32 or 34 for inward and outward folding movement relative thereto. The other edge 60 of the triangle defined by each side wall end section 54 is arranged to be substantially horizontal and in opposed relation to the corresponding edge of the adjacent side wall end section when the enclosure is in the expanded condition shown in FIG. 2.

As stated above, when the unit is in its collapsed condition, all of the aforedescribed hinged wall sections, i.e., end wall sections 32 and 34, side wall main sections 42 and 46, and side wall end sections 54, are arranged to be folded inwardly into a position generally parallel to and arranged between the base 20 and top 30 of the unit, as shown in FIGS. 1 and 3. In order to enable the folding of the hinged wall sections to such collapsed condition, the underside of the top 30 and the upper side of the base 20 are recessed (the base by its upstanding fixed wall portions 26 and 28) to accommodate the thickness of their associated side wall main sections 46 and 42. Similarly, the inner sides of the end wall sections 32 and 34 are recessed to accommodate the thickness of their associated side wall end sections 54.

In the collapsed condition the base 20 and top 30 are separated by the folded thickness of the two end wall sections 32 and 34 at each end. This would leave a gap between the base 20 and top 30 along each side between the folded end wall sections 32 and 34. To close this gap the top 30 and base 20 are provided along their sides with depending and upstanding vertical extensions 62 and 64, respectively, which exteriorly overlap their associated side wall main sections 46 and 42 in the expanded condition of the unit. These extensions 62 and 64 have opposed horizontal edges 66 and 68 that substantially abut, and end edges 70 complementary to and which substantially abut the exposed edges of the folded end wall sections 32 and 34, in the collapsed condition of the unit, as shown in FIGS. 1 and 3.

In moving from collapsed to expanded position, the top 30 of the unit normally is translated upwardly to an initial position, shown in FIG. 4, by outward pivotal movement of the end wall sections 32 and 34 about their respective hinges 36 and 38. During this movement it will be seen that the side wall main sections 42 and 46 also commence to pivot outwardly about their longitudinal horizontal hinge axes 44 and 48 while at the same time the side wall end sections 54 tend to pivot outwardly about their hinged connections with their corresponding end wall sections. The movement continues until the roof 30 and the end wall sections 32 and 34 reach the positions shown in FIG. 5 wherein the roof is at a position of maximum separation from the base 20. In this position the hinge axes 36, 38, and 40 at each end of the unit are coplanar, while the end wall sections 32 and 34 which are hinged together attain a nearly coplanar position at an angle of 180.degree. with each other. Desirably, however, the hinged wall sections are proportioned so that outward movement of all of the wall sections continues to the "over-the-center" position shown in FIG. 6 wherein the roof 30 commences to move back downwardly toward the base 20. In this position it will be seen that the side wall end sections 54 are at an angle less than 180.degree. to their associated side wall main sections 42 and 46, and the latter are at an angle less than 90.degree. to their associated base 20 and top 30. Outward movement of the hinged wall sections continues, however, to an over-the-center expanded condition shown in FIG. 7 wherein the end wall sections 32 and 34 of each hingedly connected pair are at an angle less than 180.degree. to each other, all of the side wall main sections 42 and 46 are at an angle of the order of 90.degree. to the base 20 and top 30, and wherein the side wall end sections 54 are coplanar with their associated side wall main sections.

In this fully-expanded position it will be seen that the side wall sections 46 and 54 associated with the roof 30 have edges 52 and 60, respectively, which are in abutting relation with corresponding edges 50 and 60, respectively, of the side wall sections 42 and 54 associated with the base 20. This abutting relationship constitutes stop means which prevents further downward movement of the top 30 relative to the base 20 and constitutes means for retaining, under the weight of the roof 30 and the wall sections 32, 46, and 54 associated therewith, the unit in its fully-expanded condition without any further means which requires adjustment. Preferably, all the free edges of the side wall sections associated with the roof 30 are in abutting relationship with all the free edges of the corresponding side wall sections associated with the base 20 but it will be seen that an abutting relation between the free edges of any pair of upper and lower corresponding side wall sections will perform the aforedescribed stop function. This stop function can also be attained by providing end wall sections 32 and 34 with bevelled edges adjacent their hinge axes 36, 38, and 40 which come into abutting relation with the base 20 and top 30 and with each other adjacent the hinge axes 44 and prevent further outward movement of the end wall sections once the latter have reached the expanded condition shown in FIG. 7.

With the proportion of the various wall sections shown in FIGS. 1-7, when the unit is in its fully expanded condition, the end wall sections 32 and 34 of each hingedly connected pair are of the order of an angle of 90.degree. with each other. By suitably proportioning the wall sections, however, this angle can be varied. For example, as shown in FIG. 8, this angle can be less than 90.degree., e.g., of the order of 70.degree. to provide for a construction which has a rather extended overhang at each end in the expanded condition of the unit. On the other hand, the angle can be increased greater than 90.degree. so as to considerably reduce the overhang, as shown in FIG. 9 wherein the angle between the sections 32 and 34 of each hingedly connected pair is of the order of 120.degree.. The angle can even be increased to the point where it is of the order of 180.degree. and the end wall sections 32 and 34 of each hingedly connected pair are coplanar so that there is no overhang at the ends in the expanded condition of the unit as shown in FIG. 10. In this arrangement, however, it will be seen that the linkage does not provide for an over-the-center expanded condition so that the aforedescribed stop function, achieved by the weight of the parts, is not fully realized.

Obviously depending upon the weight of the roof 30 and wall sections, the unit can be deployed manually from a collapsed condition. Such manual deployment can be facilitated, to some extent, by the use of springs. For reasons later explained such springs desirably are associated with the end wall sections 32 and 34 of each hingedly connected pair to maintain the angle therebetween at that corresponding to some condition between collapsed and expanded condition of the unit.

For example, referring to FIG. 11, there is shown a torsion bar spring 74, one at each end of the unit, constituting the hinge axis 40 between a pair of hingedly connected end wall sections 32 and 34. Opposite ends of the spring 74 are provided with right angle bends 76, one of which is secured to one end wall section, e.g., 32, and the other to the other end wall section, e.g., 34. Other structural arrangements for anchoring opposite ends of the spring 74 to the respective end wall sections 32 and 34 obviously can be had. In the arrangement shown, it will be seen that the springs 74 at each end of the unit can be proportioned and arranged so that they will retain the unit, when under no restraint, in a condition somewhere intermediate collapsed and expanded conditions, for example in the approximate condition shown in FIG. 5, i.e., wherein the roof 30 is in its position of maximum separation from the base 20 and the end wall sections 32 and 34 at each end are nearly coplanar. With such a spring arrangement, depending upon the size and weight of the parts, not too much manual effort would be required, after initially pushing the end wall sections 32 and 34 slightly inwardly, to force the roof 30 downwardly, against the restraining force of the springs 74 to fully collapsed condition of the unit and to retain the unit in collapsed position by some appropriate restraining means, such as a latch (not shown). When such restraining means is released, however, the unit will reassume the position shown in FIG. 5, and in this position not too much manual effort would be required, after initially pushing the end wall sections 32 and 34 slightly outwardly, to move the roof 30 downwardly, against the restraining force of the springs 74, to the expanded condition shown in FIG. 7 in which the unit would be retained by some appropriate restraining means (not shown). If necessary, appropriate manually operated force-multiplying means, such as jack screws having hand cranks (not shown), appropriately connected to the end wall sections 32 and 34 of each hingedly connected pair, could be used to overcome the spring forces.

Referring now to FIG. 12, there is shown another type of spring arrangement which can be used to retain the unit in a condition somewhere between collapsed and expanded conditions. This arrangement includes an elongated housing 78, rectangular in cross section, having a longitudinal slot 80 along one side. The upper end of the housing 78 is connected to a lateral edge of an upper end wall section 34 for pivotal movement about a transverse horizontal axis 82. Longitudinally slidable within the housing 78 is an element 84 connected, through the housing slot 80, to the lateral edge of the lower end wall section 32 for pivotal movement about a transverse horizontal axis 86. Connected between the element 84 and the lower end of the housing 78 is a coil spring 88. The spring 88 is proportioned and arranged so that when the unit is in a predetermined condition intermediate collapsed and expanded conditions, any relative angular movement between the two hingedly connected end wall sections 32 and 34 is restrained by the spring 88. The spring force can be overcome, however, either manually or by manually operated force-multiplying devices of the type described heretofore.

Manual development of the unit can be completely dispensed with, however, and replaced by appropriate power-operated means. Such may constitute any appropriate type of power-operated linear actuator, which can be either mechanical, hydraulic, pneumatic or electric. Thus, for example, an appropriate power-operated actuator may constitute a single acting reciprocating hydraulic motor of the cylinder and piston type. Although such power actuators could be directly connected between the base 20 and roof 30 to raise the latter, it is preferable to connect them to vary the angle between the two hingedly connected end wall sections 32 and 34 at each end of the unit, as shown in FIG. 13. It has been found that synchronous variation of this angle deploys the unit with the top 30 desirably maintained in parallel coextensive overlying relation with the base 20. In this arrangement the cylinder 90 of the motor may be pivotally connected to a lateral edge of the lower 32 of two hingedly connected end wall sections, while the outer end of the piston rod 92 is pivotally connected to the lateral edge of the upper 34 of the two end wall sections. Hydraulic fluid can be supplied under pressure to the cylinder 90 from any appropriate source (not shown) under the control of appropriate valves (not shown).

The various hinge connections of the articulated panels desirably are effected by continuous water-tight hinges which require no additional sealing arrangements at the hinge joints between the parts. A desirable hinge for this purpose is of the type shown in U. S. Pat. No. 3,320,225, to which reference is made for a detailed description of such a hinge. A hinge of this type, however, is shown in FIG. 18 which illustrates its use to connect a side wall main section 46 to the roof 30.

The hinge is in the form of an elongated strip 94 of tough but flexible plastic material having a central longitudinal portion 96, which is thinned or of reduced thickness for enhanced flexibility, substantially constituting a hinge axis while the longitudinal portions 98 and 100 of greater thickness on opposite sides of the thinned portion constitute flanges for securement of the strip to the panels to be hinged. One of these flanges, e.g., 98, is secured, as by appropriate screws 102, beneath and along the undersurface of the roof 30 along its longitudinal edge. The outer flange 100 is secured, as by screws 104, along the top edge of the side wall main section 46 which is offset inwardly from the longitudinal edge of the roof 30. As shown in FIG. 18, the underside of the roof 30 is recessed as at 106 for reception of the side wall main section 46 when the latter is folded inwardly and upwardly, to the position shown in dotted lines, about the thinned portion 96 which constitutes the hinge axis 48 for the wall section 46. From this construction it will be seen that the flexible plastic strip 94 forms a continuous sealed hinge which eliminates the necessity for other types of seals between hingedly connected parts of the unit. Thus, substantially the only edges which need be sealed are the abutting edges 50, 52 and 60 of the side wall sections which meet at a substantially horizontal parting line when the unit is in its expanded condition. These abutting edges can be sealed by any simple conventional type of compression or interfitting resilient weather-tight sealing means (not shown) secured to one or both of the abutting edges.

At that longitudinal extent of each side wall main section 42 and 46 which is exteriorly overlapped by the vertical extensions 64 and 62 along the sides of the base 20 and roof 30, the outer flange 98 of the hinge strip 94 can be shaped for appropriate securement to the interior side of such extensions.

The various end and side wall sections may be provided with windows, e.g, 108, at any desired location. These windows 108 may have glass panes because of the hard wall construction of these sections rather than being formed of a flexible but less transparent and less enduring material which usually is necessitated for soft wall constructions. The enclosure also is readily adaptable for the provision of a sectional side door 110 having two lower sections 112 and 114 which may be hingedly connected together along an axis coaxial with the hinge axis 44 of the corresponding lower side wall main section 42 so that the upper 112 of these door sections can be folded inwardly along with the side wall section 42. The lower two door sections 114 and 112 may be hinged along one side to the fixed side wall portion 28 of the base 20 and to the lower side wall main section 42, respectively, for outward swinging movement. The door 110 may be divided horizontally at the parting line between the lower and upper side wall main sections 42 and 46 to provide an upper door section 116 that is hinged to the upper side wall main section 46 to function in the manner of a Dutch door.

Referring now to FIGS. 14 to 17 of the drawings there is shown a non-planar configuration for the end wall sections 32 and 34 which has the effect of increasing the usable space within the unit. In this configuration the lower end wall section 32, when the unit is in its expanded condition, is provided, intermediate its lateral sides, with a transversely extending exterior bulge 118 having a generally horizontal bottom portion 120 adjacent the lower hinge 36 axis which merges with a generally vertical wall portion 122. These portions 120 and 122 are contoured so as to form a seat and to accommodate removable bottom and back seat cushions 124, as shown in FIG. 16. The upper end wall section 34 also is provided, intermediate its lateral ends, with a transversely extending exterior bulge 126 having a generally horizontal portion 128. The contours of the upper and lower end wall sections 32 and 34 are complementary so that they will closely interfit when the unit is in its collapsed condition and the two end wall sections are folded inwardly, as shown in FIG. 17.

While the top 30 of the unit has been described as having its underside recessed only for accommodation of the side wall sections, it will be seen that such recess can be made deep enough to serve as a storage compartment above the folded side wall sections when the unit is in its collapsed condition. The recess 106 shown in FIG. 18 is an example of such a construction.

Referring now to FIGS. 19-21 of the drawings, there is shown therein another type of actuating mechanism for moving the enclosure between collapsed and expanded conditions, along with another type of spring mechanism for normally maintaining the enclosure in a neutral position intermediate collapsed and expanded conditions. In this arrangement the actuating mechanism is connected to both of the end wall sections of the pair 32 or 34 associated with either the base 20 or the top 30 of the unit so as to synchronously vary the angle between each such end wall section and the base or the top, as the case may be.

In the system illustrated, the actuating mechanism is shown to be connected to the two end wall sections 32 associated with the base 20. Each of these sections 32 is provided, preferably adjacent a lateral edge, with a crank arm 130 which, in the collapsed position of the unit, depends below the axis 36 of the hinge connecting the corresponding section to the base 20. As shown best in FIGS. 19 and 20, these crank arms, when the unit is collapsed, preferably are confined within the peripheral outline of the base 20 and extend downwardly and outwardly toward the corresponding fixed end wall sections 26 of the base. Connected to the ends of both crank arms 130 is an endless cable 132 trained over idler pulleys 134 and 136, there being a pair for each arm, one adjacent each end of the arc of operative swinging movement of the end of the arm when the corresponding end wall section 32 moved between collapsed and extended positions, as shown in solid and dotted lines respectively in FIGS. 19 and 20. From these pulleys 134 and 136 the cable 132 is trained over a pair of idler pulleys 138 and 140 at the one end and within the lower portion of the base 20 and over another pulley 142 within the lower portion of the base adjacent its other end. Adjacent the pulley 142 is a drum 144 around which the cable 132 is wrapped so that rotation of the drum will mobe the cable selectively in opposite directions. The cable is arranged to move the crank arms 130 in opposite directions through the arcs necessary to move the end wall sections 32 between their collapsed and their expanded positions. The drum 144 is connected to an end of a transverse shaft 146 (FIG. 20) which extends through a worm and gear drive unit 148, that may be operated by a manually-operable crank 150 or by any suitable power-operated motor, e.g., electric, hydraulic, or the like (not shown).

The shaft 146 desirably extends transversely across the unit to the other side and has a similar drum (not shown) connected to its other end for operating a cable trained over pulleys and connected to crank arms on the end wall sections 32 on the other side of the unit to duplicate the actuating mechanism on that side.

Also shown in FIG. 19 is a spring-operated counter-balance arrangement for yielding resisting movement of the unit from a position somewhere between collapsed and expanded positions. In the arrangement shown in the drawings in dot-dash lines this intermediate position is one wherein the top or roof 30 of the unit is in its position of maximum separation from the base 20, and where the hinge axes 36, 40, and 38 of the end wall sections 32 and 34 at each end are coplanar, as also shown in FIG. 5.

This counter-balance system also includes crank arms 152 on and adjacent the lateral edge of the end wall sections 34 associated with the top 30. These crank arms 152 in the collapsed position of the unit, extend above their respective axes 38 and outwardly at an angle toward the respective ends of the unit. Preferably, the arms 152 are maintained, in all positions of the unit, within the peripheral outline thereof. A cable 154 is connected, at each end thereof, to the outer ends of both crank arms 152 and trained over idler pulleys 156, one cloasely adjacent the end of each arm when the unit is in its neutral position as shown in dot-dash line in FIG. 19. The cable 154, intermediate its ends, is wrapped around a drum 158 on one end of a transverse shaft 160 preferably having a similar drum 162 (FIG. 21) on its other end around which is wrapped the intermediate part of another cable 164 connected to crank arms (not shown) on the other sides of the end wall sections, 34 in order to duplicate the arm, pulley, cable and drum counter-balance arrangement on each side of the unit. Wrapped around the shaft 160 in end-to-end relation are two coil torsional springs 166 and 168. The adjacent ends of the springs 166 and 168 are secured to the shaft 160 by any appropriate means, e.g., a rivet 170, while the opposite ends of the springs, i.e., adjacent each end of the shaft, are fixed to the top 30, as by being fastened by bolts 172 to a transverse stiffening member 174. It will be seen that rotation of the shaft 160 is yieldingly resisted by the springs 166 and 168. These springs 166 and 168 are arranged so that they normally will retain the parts of the unit in the position shown in dot-dash lines in FIG. 19, i.e., intermediate collapsed and expanded positions.

As shown in FIG. 21, the torsion spring arrangement can be replaced by an appropriate coil tension spring 176, which may extend longitudinally of the unit and have one end anchored to the tope 30, as by being secured to a transverse stiffening member 178 by a bolt 180 having a hook on one end. The other end of the spring 176 is connected by two cables 182 and 184, one of which is trained over an intermediate idler pulley 186 to the outer ends of the crank arms 152 of the end wall sections 34 associated with the roof 30. Of course, the counter-balance spring arrangements could easily be mounted within the base 20 and connected to the crank arms 130 of the end wall sections 32 associated with the base.

It thus will be seen that the objects of this invention have been fully and effectively accomplished. It will be realized, however, that the specific embodiment shown and described is susceptible to modification without departure from the principles of the invention. Hence, the invention encompasses all modifications within the spirit and scope of the following claims.

Claims

What is claimed is:

1. A collapsible and expandable enclosure comprising:

generally rectangular, generally coextensive, and generally parallel top and bottom members movable vertically apart from a closely-adjacent collapsed position to a spaced-apart expanded position, each of said members having associated therewith:

a pair of generally rectangular end wall sections;

a pair of generally trapezoidal side wall main sections; and

two pairs of generally triangular side wall end sections one for each end of each of said side wall main sections,

the planar dimensions of the wall sections associated with one of the members being substantially the same as those of the corresponding wall sections associated with the other of said members,

all of said sections being movable from collapsed positions between and generally parallel to said members,

said end wall sections being hinged to the ends of their associated member for pivotal movement about parallel axis from said collapsed positions to expanded positions at an angle of at least 90.degree. to said member,

the end wall sections associated with one of said members being hinged to the corresponding end wall sections associated with the other of said members for relative pivotal movement about axes parallel to said first-mentioned axes,

said side wall main sections being hinged to the sides of their associated member for pivotal movement about parallel axes from said collapsed positions to expanded positions at an angle of substantially 90.degree. to said member,

said side wall end sections each being generally in the shape of an isosceles triangle having its base hinged to the side of the adjacent end wall section and having one of its sides hinged to the end of the adjacent side wall main section for movement with said sections to which hinged from said collapsed position to an expanded position generally coplanar with said adjacent side wall main section.

2. The structure defined in claim 1 including stop means operative when the end wall sections are in their expanded positions to maintain their said expanded angle of at least 90.degree. with their associated member.

3. The structure defined in claim 2 in which the stop means comprises abutting edges of a side wall section associated with one of said members and of the corresponding side wall section associated with the other of said members.

4. The structure defined in claim 3 in which the end wall sections in their expanded positions are at an angle greater than 90.degree. to their associated members.

5. The structure defined in claim 1 in which the end wall sections in their expanded positions are at an angle greater than 90.degree. to their corresponding members.

6. The structure defined in claim 1 including actuator means connected to each two corresponding hingedly connected end wall sections for adjusting the angle there between to expand or collapse the enclosure.

7. The structure defined in claim 6 including means for synchronizing the operation of both of the actuator means.

8. The structure defined in claim 1 including spring means connected to each two hingedly connected end wall sections for yieldingly resisting relative angular movement therebetween from a neutral relative angular position between collapsed and expanded positions of said end wall sections.

9. The structure defined in claim 1 in which the enclosure is a mobile wheeled shelter adapted to travel in an endwise direction.

10. The structure defined in claim 1 in which the bottom member includes a peripheral upstanding fixed wall to which are hinged the end wall sections and side wall main sections associated with the bottom member to provide a stowage compartment beneath said sections when the enclosure is collapsed.

11. The structure defined in claim 1 in which at least one of the members is provided with fixed sidewall portions along its opposite side extending between the associated end wall sections when the latter are in their collapsed positions to at least partially close peripheral gaps between the members when the enclosure is collapsed.

12. The structure defined in claim 1 in which at least one of the end wall sections hinged to the lower member is contoured intermediate its sides to define in its expanded position an exterior bulge and an interior recess having intersecting generally horizontal and generally upright portions and the end wall section hinged to said one end wall section is complementarily contoured to conformingly interfit with said one end wall section when said sections are in their collapsed condition.

13. The structure defined in claim 1 in which the members and sections are formed of rigid material.

14. The structure defined in claim 1 in which the top member includes a peripheral depending fixed wall to which are hinged the end wall sections and side wall main sections associated with said top member to provide a stowage compartment above said sections when the enclosure is collapsed.

15. The structure defined in claim 1 including actuator means connected to at least one of the members and to the pair of end wall sections associated therewith for synchronously adjusting the angle between said one member and each of said end wall sections to expand or collapse the enclosures.

16. The structure defined in claim 15 in which the actuator means includes a crank arm on each of the sections, and cable means connected to both of said arms, and drum means for moving said cable means.

17. The structure defined in claim 1 including spring means connected to the pair of end wall sections associated with one of the members for yieldingly resisting relative angular movement between said sections and said one member from a neutral relative angular position between collapsed and expanded positions of said sections.

18. The structure defined in claim 17 including a crank arm on each of the sections and cable means connected to said arms and to both of said arms and to the spring means.