GB2091095A

GB2091095A - Umbrellas

Info

Publication number: GB2091095A
Application number: GB8101707A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1981-01-21
Filing date: 1981-01-21
Publication date: 1982-07-28

Abstract

An air-inflatable umbrella 1 includes a piston 24 within the shaft and, preferably, a telescopic tube system 16, 17 so dimensioned that a single stroke will inflate collapsible air-sacs 2-5 supporting a pliable canopy. The air volume, and hence the overall size of the umbrella in its closed position, is minimized by using a square canopy and only four air sacs. The latter are formed as 30-cm long wedge-shaped envelopes, with the walls constrained by rib-welding, the open side of each being about 5cm in extent and bonded to a manifold connecting member having four air ways connecting with an axial bore. This member contains a valve and is fixed into the shaft. The piston 24 is withdrawable to act as a handle and may contain a further extension rod. <IMAGE>

Description

SPECIFICATION Improvements in umbrellas The use of air under slight pressure to distend pliable sheet material into structures is well-known.

The principle has obvious application for temporary structures such as awnings and umbrellas. To date there exists no practicable umbrella construction using this principle that possesses an efficient and quick mode of inflation and which is conveniently small when deflated. The present invention discloses an umbrella construction comprising a pliable membrane to serve as a canopy characterized in that the shaft is hollow and formed to contain air that will be used for inflation when a piston-like member contained within the shaft is pushed in.

In a preferred embodiment of the invention the shaft comprises an outer casing housing a telescopic system of tubes and is so dimensioned that after the system of tubes is fully opened out sufficient air is contained for a single stroke of the tube-piston arrangement to inflate with sufficient rigidity a plurality of air-sacs that are attached to the canopy and extend it as they themselves distend.

The central feature of the embodiment herein disclosed is the optimization of all dimensions by an integral design to give the smallest possible size when the umbrella is closed when not in use, consistent with a total air-volume of the telescopic system sufficient to inflate the air-sacs at a single stroke. To this end the overall volume of the air-sacs is minimized by (a) using a minimum number and (b) using minimum dimensions. Thus Fig. 1 shows a canopy 1 that because of its generally square shape requires onlyfourwedge-shaped air-sacs 2,3,4 and 5, about 30cm in length, to extend it. The air-sac is shown in Fig. 2 and consists of two thin wedge-shaped walls 6, 7 joined at their common hypotenuse but separated by a narrow wedge-shaped section 8 so that when distended the cross-section is roughly triangular.

The walls are prevented from distending too far by welds, or adhesive contact forming 'ribs' 9.

Fig. 3 is a cross-section through the umbrella shaft showing the telescopic tube system fully closed. The head 10 is shown in perspective in Fig. 4 and connects the tube system with the air-sacs. The latter are fixed by welding, or by adhesive, to projecting rims 11 (Figs. 3 and 4) framing openings in a connecting manifold (See Fig. 4, described later) which is itself fixed into the outer casing 15 of the umbrella. The latter is approximately 18cm in length and houses two telescopic tubes 16, 17 slightly thickened at the top as shown at 18 and 19 where the overall thickness is 2 mm. The slight gap between the tubes facilitates easy sliding. Rims 21, 22, 23 at the lower ends of the tubes prevent separation in the fully extended position.

A central piston comprises a head 24 with an axial bore 25 supported on a tube 26 of 1.5mm wall thickness and housing a solid rod 28 which is movable by means of its lower end 29 which projects when the tube system is fully closed. The system is held in its closed condition by means of the cap 30 which has slots (not shown) at its periphery 31 engaging with studs (not shown) on the casing tube 15 in bayonet connexion.

Thepumping action is commenced by releasing the cap and pulling it downwards to extend the entire tube system. At this stage the piston-tube 26 will move with the cap because of its tight frictional engagement with the latter in the thickened portion 32. The cap and piston are then together pushed home closing tubes 16, 17 in the process and all the air that was contained in the opened-out system will thus be driven through the bore in the connecting member 10 (Figs. 3 and 4) into the air-sacs.

The connecting member 10 is formed as a unitary piece with an axial bore and seating 13 fixed into the tube 15, the flange 14 giving accurate engagement so that the bevelled head 24 of the piston will just abut a matching bevel in the connecting member.

The axial bore 12 connects with four openings in the cylindrical wall which are surrounded by rims 11 to which the air-sacs are attached as already described.

Just below these openings is fixed a non-return valve 33.

An inlet valve 34 is also provided so that no vacuum will form when the piston is withdrawn, once the canopy has been distended, for the purpose of providing a handle. To this end, the cap 30 is twisted to lock the tube system and the piston tube pulled out of its frictional engagement with the cap. Further extension of the handle may be obtained by then pulling the rod 28 from inside the piston 26. Its complete withdrawal is prevented by circlips and grooves in known manner. This rod is preferably of metal, for example, aluminium and may carry a ring (not shown) for convenience. The axial bore 25 in the piston head allows entry of air when the rod 28 is being withdrawn.

The umbrella may be deflated by withdrawing a bung 35 from the upper end of the axial bore in the connecting member, when the air-sacs will collapse and may be folded around the shaft.

The overall length of the umbrella is about 20cm and the diameter of the casing 15 is about 30mm so that it may truly be described as pocket-size. The tubes and head 10 are preferably constructed from rigid P.V.C. so that the air-sacs may be of thin plasticized P.V.C. and easily bonded by adhesive. It is emphasized, however, that any suitably rigid plastics, or other, material may be used for the rigid parts while any pliable material, including rubber, may be used for the air-sacs and the canopy.

Although no details are here disclosed the invention may easily be adapted by those skilled in the art to include a simple compression spring or gas-filled compression chamber which is loaded by the closing of the umbrella's tube system and which, on release, will automatically extend the shaft in known manner.

Within the scope of the invention is also envisaged a tube system including a chamber for compressing air that will subsequently be used for distending the air-sacs.

1. An umbrella comprising a pliable membrane to serve as a canopy and inflatable air-sacs adapted to extend and support the canopy, characterized in

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Improvements in umbrellas The use of air under slight pressure to distend pliable sheet material into structures is well-known. The principle has obvious application for temporary structures such as awnings and umbrellas. To date there exists no practicable umbrella construction using this principle that possesses an efficient and quick mode of inflation and which is conveniently small when deflated. The present invention discloses an umbrella construction comprising a pliable membrane to serve as a canopy characterized in that the shaft is hollow and formed to contain air that will be used for inflation when a piston-like member contained within the shaft is pushed in. In a preferred embodiment of the invention the shaft comprises an outer casing housing a telescopic system of tubes and is so dimensioned that after the system of tubes is fully opened out sufficient air is contained for a single stroke of the tube-piston arrangement to inflate with sufficient rigidity a plurality of air-sacs that are attached to the canopy and extend it as they themselves distend. The central feature of the embodiment herein disclosed is the optimization of all dimensions by an integral design to give the smallest possible size when the umbrella is closed when not in use, consistent with a total air-volume of the telescopic system sufficient to inflate the air-sacs at a single stroke. To this end the overall volume of the air-sacs is minimized by (a) using a minimum number and (b) using minimum dimensions. Thus Fig. 1 shows a canopy 1 that because of its generally square shape requires onlyfourwedge-shaped air-sacs 2,3,4 and 5, about 30cm in length, to extend it. The air-sac is shown in Fig. 2 and consists of two thin wedge-shaped walls 6, 7 joined at their common hypotenuse but separated by a narrow wedge-shaped section 8 so that when distended the cross-section is roughly triangular. The walls are prevented from distending too far by welds, or adhesive contact forming 'ribs' 9. Fig. 3 is a cross-section through the umbrella shaft showing the telescopic tube system fully closed. The head 10 is shown in perspective in Fig. 4 and connects the tube system with the air-sacs. The latter are fixed by welding, or by adhesive, to projecting rims 11 (Figs. 3 and 4) framing openings in a connecting manifold (See Fig. 4, described later) which is itself fixed into the outer casing 15 of the umbrella. The latter is approximately 18cm in length and houses two telescopic tubes 16, 17 slightly thickened at the top as shown at 18 and 19 where the overall thickness is 2 mm. The slight gap between the tubes facilitates easy sliding. Rims 21, 22, 23 at the lower ends of the tubes prevent separation in the fully extended position. A central piston comprises a head 24 with an axial bore 25 supported on a tube 26 of 1.5mm wall thickness and housing a solid rod 28 which is movable by means of its lower end 29 which projects when the tube system is fully closed. The system is held in its closed condition by means of the cap 30 which has slots (not shown) at its periphery 31 engaging with studs (not shown) on the casing tube 15 in bayonet connexion. Thepumping action is commenced by releasing the cap and pulling it downwards to extend the entire tube system. At this stage the piston-tube 26 will move with the cap because of its tight frictional engagement with the latter in the thickened portion 32. The cap and piston are then together pushed home closing tubes 16, 17 in the process and all the air that was contained in the opened-out system will thus be driven through the bore in the connecting member 10 (Figs. 3 and 4) into the air-sacs. The connecting member 10 is formed as a unitary piece with an axial bore and seating 13 fixed into the tube 15, the flange 14 giving accurate engagement so that the bevelled head 24 of the piston will just abut a matching bevel in the connecting member. The axial bore 12 connects with four openings in the cylindrical wall which are surrounded by rims 11 to which the air-sacs are attached as already described. Just below these openings is fixed a non-return valve 33. An inlet valve 34 is also provided so that no vacuum will form when the piston is withdrawn, once the canopy has been distended, for the purpose of providing a handle. To this end, the cap 30 is twisted to lock the tube system and the piston tube pulled out of its frictional engagement with the cap. Further extension of the handle may be obtained by then pulling the rod 28 from inside the piston 26. Its complete withdrawal is prevented by circlips and grooves in known manner. This rod is preferably of metal, for example, aluminium and may carry a ring (not shown) for convenience. The axial bore 25 in the piston head allows entry of air when the rod 28 is being withdrawn. The umbrella may be deflated by withdrawing a bung 35 from the upper end of the axial bore in the connecting member, when the air-sacs will collapse and may be folded around the shaft. The overall length of the umbrella is about 20cm and the diameter of the casing 15 is about 30mm so that it may truly be described as pocket-size. The tubes and head 10 are preferably constructed from rigid P.V.C. so that the air-sacs may be of thin plasticized P.V.C. and easily bonded by adhesive. It is emphasized, however, that any suitably rigid plastics, or other, material may be used for the rigid parts while any pliable material, including rubber, may be used for the air-sacs and the canopy. Although no details are here disclosed the invention may easily be adapted by those skilled in the art to include a simple compression spring or gas-filled compression chamber which is loaded by the closing of the umbrella's tube system and which, on release, will automatically extend the shaft in known manner. Within the scope of the invention is also envisaged a tube system including a chamber for compressing air that will subsequently be used for distending the air-sacs. CLAIMS

1. An umbrella comprising a pliable membrane to serve as a canopy and inflatable air-sacs adapted to extend and support the canopy, characterized in that air used to initially inflate the sacs is, in the stage prior to inflation, contained in the shaft, the latter including at least one movable member serving as a piston for driving the air into the said air-sacs.

2. An umbrella as in Claim 1 in which the shaft comprises an outer cylindrical casing housing a plurality of tubes telescopically engaging in substan tally air-tight manner.

3. An umbrella as in Claim 1 or Claim 2 in which the piston member is adapted for withdrawal after the driving stroke for the purpose of providing a handle for gripping and is adapted to remain in air tight engagement with the shaft or tube in which it moves.

4. An umbrella as in any preceding claim in which the piston member is itself hollow and houses a withdrawable rod for the purpose of serving as an extension handle.

5. An umbrella as in any preceding claim in which the piston near its outer end is in a tight frictional engagement with a cup-shaped member adapted for fitting over the outermost shaft when the piston is fully driven home.

6. An umbrella as in Claim 2,3,4 or 5 in which the piston near its outer end is in tight frictional engagement with a cup-shaped member adapted for fitting over the shaft when the piston, together with the telescopic tubes have been fully driven home, the cup-shaped member being provided with slots and the adjacent portion of the outer tube with stubs, or vice versa, for engaging in bayonet connexion.

7. An umbrella as in any preceding claim in which the shaft, tube members and air-sacs are so dimensioned that a single stroke will inflate the sacs.

8. An umbrella as in any preceding claim including a connecting piece with manifold air-ways com municating with an axial bore adapted to connect in air-tight engagement with the shaft and to have an air-sac connected, in air-tight engagement with each air-way.

9. An umbrella as in Claim 8 in which the airways vents on the outer surface of the connecting member are surrounded by a raised rim that serves as a hollow stub for attaching thereto of the air-sac.

10. An umbrella as in Claim 9 in which the air-sac is secured by welding or adhesive.

11. An umbrella as in Claim 9 in which the airsacs are integrally formed with the connecting member.

12. An umbrella as in any preceding claim in which each air-sac is formed with two walls of roughly wedge shape, these two walls being everywhere around their periphery in air-tight connexion except at the wide end.

13. An umbrella as in Claim 10 or 11 in which the walls are held fast together at isolated points by welding or adhesive to prevent excessive separation of the walls when the air-sac is inflated.

14. An umbrella as in Claim 13 in which the wedge shape is roughly a right-angled triangle in which the hypotenuse side is presented upwards and secured to the canopy.

15. An umbrella as in any preceding claim in which the canopy is bounded by four sides and there are four air-sacs disposed along the diagonal directions in such a manner as to hold the canopy in a shallow pyramidical disposition when the air-sacs are inflated.

16. An umbrella as in any preceding claim in which the air-sacs are formed of thin membranes that may be wrapped around the shaft when the airsacs are empty of air.

17. An umbrella as in any preceding claim in which a non-return valve is provided for the passage of air therethrough to the air-sacs.

18. An umbrella as in any preceding claim in which a further air valve is provided either in the connecting member or the outermost tube to allow ingress of air when the telescopic tube system is extended.

19. An umbrella as in any preceding claim in which a removable bung is provided for releasing air from the air-sacs.

20. An umbrella as in any preceding claim including a compression spring or compressed airchamber loaded by closing the umbrella and adapted to automatically extend and inflate it when released.

21. An umbrella substantially as described in the above specification with reference to the accompanying drawings.

22. An air-sac for an inflatable umbrella substantially as described.

23. Atelescopictube system for an inflatable umbrella substantially as described.

24. Aconnecting member with a central base and communicating airways substantially as described.

25. An umbrella as described including any of the modifications contained in the final paragraphs ofthe specification.