Tent structure and suspension means

[57] ABSTRACT

A tent structure with a support means distributing a tensioning force equally across the width of the sidewall membrane, having a floor in free suspension and top supported at its apex by an upward force with a large vent and skylight occupying the apical portion of a top.

Claims, 10 Drawing Figures

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PATENTED JUL29I975

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3,896,830

PATENTED JUL 2 91975

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PATENTEDJUL29I975

SHEET

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3.896.830 part of the tent. Such openings are by necessity closed in inclement weather and not available for ventilation. These factors in turn are aggravated by the small cubic capacity of a tent per occupant increasing the need for 5 a large ventilation factor. In cold or freezing weather water released to the atmosphere of the tent by the bodies of the occupants (up to one quart per day per person) condenses and freezes on the inside of the tent making occupancy unbearable. Adequate ventilation 10 corrects this by passing such moisture continuously to the outside air.

Such ventilation means should be located at the apex of the top, be capable of moving large volumes of air, should vent to all sides of the structure to take advan15 tage of the positive and negative wind pressure effects on opposite sides of the top to encourage the flow of air. Such a ventilator permits use of a waterproof membrane as the top of a tent without the disadvantages of retaining heat, odors and moisture within the structure.

Such a vent functions as a large skylight in fair weather by removing its waterproof cover.

SUMMARY OF THE INVENTION

The invention consists of a novel means of tensioning 25 a membrane at a variable distance from the ground to form an upright wall. Membranes may be attached in free suspension to the lower edge of such a wall to form a floor. Similarly a roof may be attached and held under tension by force applied to the apex of the roof ³⁰ sufficient to support the dead weight of the top. In addition a vent is incorporated into the uppermost part of the top to provide for ventilation and light. Such means for tensioning a membrane allows great force to be applied to the wall without tearing or deformation. This ³- permits heavy external load resistance and the use of a minimum of anchors.

Only a minimal tensioning force is needed to erect the top which permits use of lightweight material, simple seam construction, insertion of a large vent covered ⁴⁰ with insect proof mesh in the apex and lightweight support devices. Such tensioning force is applied to the apical aspect of the top either by an upright pole from within or by suspension from an overhead anchor. No tensioning force is exerted on the floor membrane ⁴⁵ which is attached to the lower edge of the tensioned wall membrane in free suspension. Such a floor can be constructed as a basin without attachments or seams at the junction of the floor with its sidewall extension.

Accordingly, it is an object of the invention to pro⁵⁰ vide an upright substantially rigid support which bears on a membrane at more than two points at opposite ends of its width. Said support to transfer force from a connecting link under tension and anchored at a distance from the membrane. Said force to produce sur³ face tension in the upright membrane making it substantially rigid.

It is another object to utilize a means to join the upright support and the membrane to permit the tension₆₀ ing force to be distributed over the breadth of the membrane.

It is another object to join the upright membrane and support in such a way that the membrane may be positioned at a variable distance from the ground.

₆₅ It is another object of the invention to permit the construction of the sidewall membrane, including all wall structures, from a single and continuous membrane sheet.

TENT STRUCTURE AND SUSPENSION MEANS

BACKGROUND OF THE INVENTION

This invention is a continuation of my co-pending patent application Serial No. 278,034, filed Aug. 4, 1972, and now abandoned.

A membrane utilizing applied forces causing it to assume a predetermined shape to enclose a three dimensional area forms a tensile structure. A tent when erected is such a tensile structure. Such a structure provides wind, water, heat, cold and insect protection from without, ventilation for cooling, odors and moisture from within and a means for entry of light.

A tensioning force may be applied to such a membrane from within the structure, e.g., via upright rigid poles, from an outside frame to which the membrane is suspended, or from lines attached at multiple points on the surface of the membrane. Such force is countered and balanced by multiple anchoring points at a variable distance from the perimeter of the floor.

Disadvantages of such tensioning means includes: localized points of application of force induces tearing of the fabric, requires reinforcement of the seams and points of attachments of the floor and sidewalls, places the floor membrane on tension causing seam strain and increased friction between the floor and ground causing accelerated wear to the stretched membrane.

The apex of the top of such a structure carries the entire loading force required for tensioning. Great strain is thus applied to the seams and membrane of the top necessitating use of heavy materials and reinforcements resulting in disadvantages of heavy weight and costly construction.

Other disadvantages are need for a large number of anchoring devices, complicated support construction, erection means limited to a single system requiring special devices and need for multiple panels and their fabrication in construction of the tent membrane.

To prevent upset or deformation of a light tent structure due to external loading such as wind or snow, firm anchoring to the ground and a rigid membrane under tension are required. Existing tents require up to 27 stakes for an average size structure to insure anchoring. Rigidity is still not provided in most cases due to the many localized points of attachment of the tensioning lines to the tent resulting in great elasticity.

Most existing tent structures are water resistant only. This results from the use of a permeable membrane in the tent to provide ventilation through the pores of the membrane to the exterior. When such a membrane is wetted the pores fill with water and ventilation function is lost. Heavy rain results in leakage to the inside. A waterproof tent uses a nonpermeable membrane resulting in an uncomfortable interior due to retained heat, moisture and odors.

Water protection from the ground requires a waterproof membrane as a floor extending up the sides for a variable distance. Existing tents have seams joining the floor with the sidewalls with numerous attachment devices for anchoring. This introduces weak areas which tear under strain and are difficult if not impossible to waterproof. Such a floor is also under tension increasing its friction with the ground and hence its durability. Ventilation and light are also inadequately provided for in existing tent structures. Doors and windows used for this purpose are located in the lower portions of the structure leaving a large dead space in the upper

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It is another object to permit the construction of a floor with sidewalls in free suspension from the upright walls without seams or attachments at the junction of the floor and sidewalls.

It is another object to permit the construction of a top attached to the upright walls and tensioned by a force acting at its apex.

It is another object to construct a waterproof fly for the entire tent containing a vent in its apex opening to all sides.

It is another object of the invention to permit erection of the tent in a variety of ways utilizing simple and inexpensive support devices.

It is another object to use a novel means as the preferred way for forming and joining the connecting link from the anchor to the upright wall support.

It is another object to use a unique and simple means to construct a vent in the apex of the top.

It is a further object to provide a wall membrane support means which may be of variable shape and height and tensioned at a variable angle to the ground.

It is a further object of the invention to be applicable as a module multiples of which may be used for tent construction of various sizes.

It is another object that the tent shape may be varied in many ways utilizing this erection means.

It is a further object to use a minimum of anchoring devices.

It is a further object to eliminate any tension from the floor and to limit the tension on the top to that necessary to support the dead weight of the fabric.

It is another object to construct a removably fly to cover the vent in the apex of the top.

It is another object for the vent in the apex to function as a skylight with the fly removed.

It is another object to eliminate any attachment devices to the floor.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a tent structure suspended as described in this invention;

FIG. 2 is a horizontal section taken on the line 2 2 of FIG. 1 through a sidewall support unit;

FIG. 3 is a vertical section taken on the line 3—3 of FIG. 1 through a sidewall support unit;

FIG. 4 is a horizontal section taken on the line 4—4 of FIG. 1 through the lower portion of the vent and skylight with the removable waterproof fly in place;

FIG. 5 is a vertical section taken on the line 5 5 of FIG. 1 through the entire vent and skylight with the removable waterproof fly in place;

FIG. 6 is an exploded view of the parts of the tent and detailing the method of inletting the vent panel,

FIG. 7 is a side view of the tensioned and suspended tent structure covered in its entirety by a waterproof fly containing an opening in all sides opposite the vent in the tent top;

FIG. 8 is a horizontal section taken on the line 8 a of FIG. 7 illustrating the relationship between the fly with its opening and the vent in the apical portion of the top proper; .,

FIG. 9 is a vertical section taken on the line 9 9 of FIG. 7 illustrating the relationship between the fly with its opening and the vent in the apical portion of the top of the tent proper;

FIG. 10 is a vertical section taken on the line 10 10 of FIG. 7 through the floor and sidewall.

DESCRIPTION OF THE PREFERRED EMBODIMENT

As shown in FIG. 1 the invention consists of a means 5 for tensioning a membrane forming a sidewall 19 for a tent structure.

The tent as illustrated is eight feet square with a pyramidal top 6 supported at the center by a center pole 26. The center pole 26 may be eliminated by suspending 10 the top via a loop 1 from an overhead anchor (not shown) such as a pole, frame, tree or other support. This structure as illustrated can serve as a module, multiples of which can be joined together producing various sizes and shapes. The sidewalls 19 are tensioned 15 with four corner units, as shown in FIG. 3, tied to four anchoring stakes 9. It is apparent that the height of the sidewalls 19 and the length and width of the tent structure can be varied without departing from the principles of the invention. It is to be noted that only four an20 chors 9 are sufficient for rigid erection of this module in contrast to up to twenty-seven in conventional tent structures.

All tensioned seams 5, 32, 25, etc. are preferably formed as catenary curves to reduce tensioning stresses 25 and reduce the number of tensioned seams required.

The membrane support units as shown in FIG. 3 consist of substantially rigid lightweight tubes 12, such as aluminum pipe, which are passed through membrane folds 11. The tubes preferably are level with the top of ³⁰ the folds 11 and project beyond the bottom of the fold 11 by the extent of the height of the sidewalls above the floor 13. This distance will vary, but four to six inches is usually sufficient. It is readily apparent that any substantially rigid supports can serve the same function as ³⁵ lightweight tubes 12 by attaching the connecting link 8 to their opposite end portions.

The fold 11 in the sidewall membrane 19 is formed by folding the membrane 19 and stitching it together at the base 25 of the fold. This can be done in with contin⁴⁰ uous material thereby avoiding cutting and reassembling separate sidewall panels and folds 11. Such continuous construction of the membrane support folds 11 allows the membrane 19 itself to carry the tensioning force without multiple interposed seams that present ⁴⁵ weak areas and require costly construction. Most of the tensioning force needed for the tent suspension is distributed over the width of the sidewall 19. The floor 13 is free of horizontal tension and the top 6 carries only that needed to support its own weight. Doors 14 and ⁵⁰ windows 15 are cut from the same membrane to form flaps thereby permitting the entire sidewall 19 to be constructed with the single seam to join the ends of the enclosure. Suitable means such as a zipper, may be used to open and close the edge of the flaps forming the doors and windows. A rope line 8 is passed from above downward through the support tube 12 from a loop 7 formed in its end, out through the bottom of the tube 12, a second loop 7' being formed in continuity with the line 8 about a foot from the pole 12. The line 8 is ⁶⁰ then passed around an anchor 9, then angularly upward and through the loop 7 in the end of the line 8, down and through the loop 7' in the horizontal limb and back up to an adjustable fastener 10. Ί his forms a truss-like structure which produces a tensioning force by short⁶⁵ ening the interconnecting link 33 thereby moving the two sections of the line 8 at either end of the connecting link towards each other and forcing the support

3,896,830 weather. It is apparent that the mesh may be placed at other locations to screen the vent and that the edges 5 leading from the corners of the tent to the apex of the tent supporting the tensioning force may be con5 structed of any suitable material able to support such force without departing from the essence of the invention. The top so constructed is then joined to the top edges of the wall membrane 19.

The very peak of the apex is reinforced by stitching 10 in a small disc' of strong material inside and out to which is attached a thin loop of line 1. This provides a reinforced point for the apical tensioning force to act against.

Because of the large ventilation capacity of the vent 15 16 the top of the tent and the vent cover 2 may be made of nonpermeable waterproof material for total protection from external moisture. When a waterproof fly 24 and 25 covering the entire tent is used the tent top 6 is made of a permeable membrane without a vent cover 20 2, which results in lower weight and cost.

The vent cover 2 is made of four panels joined together in the shape of the vent panels 16, their lower edge 37 being curved upward in the center in the shape of a catenary curve and overhanging the lower edge 21 25 of the vent panel 16 for several inches. The peak of the cover has a small opening, such as an O-grommet, to permit the passage of the loop 1 from the apex of the vent 16. The cover 2 has a fastener at point 28, such as velcro, to attach to a point on the raised edge 5 to hold ³θ it in place. A second fastener, such as velcro, is placed at the midpoint of the lower edge 22 to attach to the point 23 on the tent top 6 to provide for closure of the vent opening 3 as needed.

A waterproof fly 24 and 25 covering the entire tent, ³³ projecting beyond the walls 19, with a vent 3 near its apex on all sides opening to the vent 16 in the tent top, with the edges of the lower panels 25 curved upward in a catenary curve. The edges can be tensioned by lines 38 connected to anchors 9 at all four corners. The peak ⁴⁰ is supported by an upward force acting at the apex of the tent top. The cover 24 to the vent opening extending upward to enclose the upper edge of the fly 25 is constructed in an identical way to the cover 2 previously described for the vent 16 except that it is perma⁴³ nently fastened to the corner seams at and below the horizontal line of closure to the vent opening 3.

It is readily apparent that multiple openings 3 can be placed in each side panel of fly 2 or fly 24 thus increasing air flow and ventilation. Such openings 3 placed ³⁰ transversely can be formed by joining the adjacent sides of the fly 2, 24 by means of detachable fasteners such as velcro to the sides of the underlying vent panels 16 thereby inletting the intervening portions of each ₅₅ side 2. A covering membrane is attached at all corners ^J to the above membrane spanning the inletted portion forming an opening 3 and overhanging the upper edge of the inletted portion of the fly sufficient to prohibit the entry of moisture. Said covering membrane extends 6θ to the apex of the tent where a small opening such as an O-grommet is placed for passage of loop 2.