US1485400A - Parachute - Google Patents

Description

March 4 1924.

O. D. LUCAS PARAcHU'rE Filed Sept. 28

1922 3 Sheets-Sheet 1 0. D. LUCAS PARACHUTE March 4 1924.

3 Sheets-Sheet 2" Filed ept. 28', 1.922

March 4, 1924. 1,485,400

4 O. D. LUCAS PARACHUTE Filed Sept. 28 1922 3 Sheets-Sheet 3 OWEN DAVID LUCAS, OF BAYSWATER, LONDON, ENGLAND, ASSIGNOR T9 VQIH. L. PERIMEINTAL LIMITED, OF WESTMINSTER, LONDON, ENGLAND.

PABACHUTE.

application filed September 28, 1922. Serial iillo. 591,611.

To all whom it may concern:

Be it known that I, Owen DAVID Lucas, a subject of the Kin of Great Britain, residing at 49 Linden gardens, Bayswater, in the county of London, England, have invented certain new and useful Improvements in or Relating to Parachutes, of which the following is a specification.

This invention relates to the manufacture of parachutes, especially such as are intended for pyrotechnic purposes, where light or smoke signals or flares are to be shown in the air, the chief objects of the invention being to increase the strength of the parachute while reducing its weight to a minimum and to allow the parachute to bemade in a very economical manner.

Parachutes for this purpose are usually made of silk, mercerized lawn or, in the case of small parachutes, of tough paper such as Japanese paper, in the latter case the seams and reinforcing strips being secured by paste or gum which greatly increases the stiffness and reduces the freedom with which the parachute opens. To obtain satis-' factory freedom of opening it is nece$ary to keep the whole parachute very light and flexible and in the constructions Hitherto emloyed this is difficult owing to the fact that the fabric, especially in parachutes of substantial size, has to be of considerable strength as the stresses are taken mainly by the fabric itself.

Small parachutes made on the lines hereinafter described may be wholly of paper but in larger parachutes made according to this invention the chief stresses during the opening and fall of the parachute are taken by reinforcing cords which pass across the fabric and are attached b gripping to the edges of the parachute. he surface of the parachute is therefore in effect divided into comparatively small sectors and the' fabric in one sector takes little of the stress due to pressure on another sector owing to the support given bfy the intervenin cords and the gripping o the cords to t e edges of the parachute, while firm enough to resist ordinary stresses on the parachute opening out, ensures yielding of the attachment in the event of a sudden excessive stress which would otherwise rip the fabric even in its reinforced condition. Such excessive stresses frequently occur, owing to the liability of the parachute to drop a substantial distance before opening out, when the sudden check on opening may give rise to violent tearing forces. The yield provided for under considerable resistance by the grip at the edges prevents such forces exceeding the strength of the fabric. Owing to the fact that the stresses.

are made and the reinforcing strips applied by means of paste, or gum, which on drying hardens and renders the parachute much stiffer at such points, the stiffness preventing the free opening which is so important for the efficiency of the parachute in use.

- To avoid this disadvantage I make a tough pa er parachute in which all joints and rein orcing strips are secured by means of a cementing composition which on drying is elastic and flexible so that the flexibility of the material is notmaterially affected at such parts. serviceable for this purpose, but airship dope or other elastic varnish may also be used. The reinforcing of the parachute is required especially around the outer edge, but it may also be applied around the small central hole and in both cases the strengthening strips of paper or other flexible-fabric are secured by the elastic and flexible cement. For larger. parachutes reinforcing strips may be cemented at suitable positions onthe surface as well as at the edges. With the rubber solution or equivalent elastic cement the parachute can be folded up into a greatly reduced space as compared with a silk or ordinary paper parachute of the same size, such reduction of bulk in the packed condition being a great advantage, especially when the parachute is to be enclosed with the signal charge in a casing adapted for dischar e from a I have foun also that paper parachutes Rubber solution is especiallyresistfree opening on falling through the air owing to a large extent to the factthat the contacting surfaces of the parachute in its folded up condition do not readily slip past one another, so that the folds are not opened up readily enough in flight. To remedy this I propose to cover the whole surface of the parachute with a lubricating material, for example French. chalk, aluminium powder or a soapy substance, the lubricant ensuring ready slipping of the surfaces past one another so that there is no tendency for the parachute to stick at the folds.

I also propose to coat the whole paper surface of the parachute with rubber solution, airship dope or elastic varnish, by the brush or spraying method, so as to form a thin waterproofing film which adds considerably to the strength of the paper and protects it from atmospheric action.

In order that the said invention may be clearly understood and readily carried into effect, the same will now be described more fully with reference to the accompanying drawings, in which Figure lis an elevation of the larger type of parachute in accordance with this invention, in dropping or extended position.

Figure 2 is a plan of the parachute in its fiat condition showing the arrangement of cords.

Figures 3 to 7 are details of the cord attachments; and

Figures 8, 9 and 10 show a small parachute without reinforcing cords, Figure 8 being an elevation of the parachute as in flight, Figure 9 a plan ofthe fiat parachute and Figure 10 a'detail of a suspension cord attachment. v

Referring first to the parachute illus trated in Figures 1 to 7, A is the main sheet or disc of the parachute formed with a small central opening a. B, B are two sets of reinforcing cords, an". outer and an inner set, as shown in Figure 2. C, C are eyelets round the edges of the parachute, which serve for attachment of the reinforcing cords B. D, D are suspending cords or guys carried by the edges of the parachute by means of the eye-lets E. The eyelets C and E are shown in detail in Figures 3 and 4. F, F are the main suspending cords or tapes attached to the cords D through the eyelets G in the manner shown in Figure 5, the main suspension cords or tapes being attached at their lower end (after passing through the collecting ring f) to the carrying member H terminating in a ring it from which the signal flare or other object is suspended.

In the special arrangement of reinforcing cords illustrated in Figure 2 of the drawings the inner cords B radiate from the center of the parachute within the hole a opposit cords looping or lacing through restate reinforcing pieces of fabric which are cemented on the disc A. An outer reinforcing ring J is secured at both sides of the disc A as shown in Figure 3, which is a section a t.the edge of the parachute. The cords B lie under the ring J at the upper side. The middle reinforcing or strengthening ring J covers the junctions of the cords B B while the inner ring J covers the middle portions of the radiating cords B. The rings J J? are preferably cemented only on the upper surface of the parachute disc. The strengthening rings J, J J may be of tough paper or thin fabric cemented on the disc A by rubber solution, aircraft dope or other resilient cement-which will not impair the flexibility of the parachute.

In the particular arrangement of eyelets shown in Figures 3 and 4 the eyelet C is passed through a hole near the edge of the reinforced portion of the parachute disc A and washers c are provided over which the eyelet is securedv by punching in the usual manner. Theflan e of the eyelet serves to bind the cord in position, the cord being passed across both sides of the eyelet so that it is securely gripped in position while an excessive force acting on the fabric would cause some slip by pulling the gripping eyelet back over the cord. The outer loop of the cord B serves to carry the outer eyelet E and passesbetween two washers e to which the eyelet is secured, so that the cord is tightly bound in position when the eyelet is punched. All stresses due to pull on the suspension cords F, D are therefore taken by the reinforcing cords B, B and the paper or other fabric of the parachute is in fact divided up into a large number of sectors of relatively small area so that the stresses on the material of the disc are reduced to a minimum.

The suspending cords or guys D are arranged in groups after the manner of a bal loo-n suspension. in Figure 1 four cords being shown as forming a group, the cords passing through the eyelets E attached to the edge of the parachute by the cords B as already described and uniting at one of the eyelets G. The groups of cords D overlap, ouch eyelet E having attached to it a cord of each udjzuvni group. The cords are doubled and looped and in the group of each forming a long an four cords two cord lengths may be used a short loop of the group.

The main suspension cords F are preferably made from silk braid and carry the eyelets G at their upper ends, the braid being doubled as shown in Figure 5 and the eyelet G secured over a pair of washers g, the double end of the braid extending a little beyond the eyelet. The loops of the cords D are passed through the eyelet and the stresses thus distributed equally over the complete set of cords, since they are free to slip through the eyelets.

In a modified method of applying the cords a cord may extend from an eye et at the edge to a large central eyelet or small drum .or equivalent device at the hole a, passing around this central eyelet and back again to a second edge eyelet, returning to the centre and passing in succession to the edge eyelets until the whole parachute is provided with the radiating strengthening cords. If the cord is wound around the central eyelet or drum it may be held in position between a pair of washers, the second of which is secured on the eyelet after wind ing the cords. A single continuous cord length maybe employed for the whole surface of the parachute, the cord being wound backwards and forwards as required or several cord lengths may be provided. Figure 1 serves to indicate an arrangement of remforcing cords of the type just described, the

lines B showing the appearance of cords passing radially from the peripheral attachment to .'the centre and back, dividing the parachute'into a number of sectors of equal size.

Where the parachute is made of a single layer of paper or fabric covering and strengthening strips or rings are secured over the cords as shown in Figure 2, but if two or more layers are employed the cords may be placed between the layers. In a paper parachute thejoints and reinforcing strips may be secured by an elastic cement such as rubber solution, airship dope: or other elastic varnish and the whole surface may also be treated by the brushor spraying method with such solution or dope to make it waterproof. To assist free opening of, the parachute the surface may be covered with a lubricant such as French chalk, aluminium powder or a soapy substance- The term cord is to be understood broadly as covering any narrow line or tape possessing the ,requisite stren h and flexibility.

Referring to the smal parachute. shown in Figures 8, 9 and 10, in which the cords are not required for strengthening purposes A is the body of the parachute formed of a circular sheet or disc of ten h pa er having the small central hole a. Fire 'sc may be single as shown or made in two or more arts ointed together, the joints being made y the cement described above. J is the reinforcing strip around the edge of the parachute and J a similar strip around the hole at. E E are eyelets to receive the cords D eight of which are shown, attached around the periphery of the parachute and brought towards one another at the connecting ring at from which they extend down to the attachment H to which they are tied, this attachment carrying a ring it serving to carry a signal flare or other object to be dropped with the parachute.

The reinforcing strips J J are as above described cemented to the paper body by an elastic cement which does not impair the flexibility at the edges. Additional reinforcing strips may if desired be secured .on the surface of the parachute, for example along radial lines from the cord eyelets E At the eyelets small strengthening pieces e are provided comprising ,discs of fabric folded over the reinforced edge of the parachute at the required points and pierced to receive the eyelet, washers 6 being also proyided at each side before punching the eye- .What I claim and desire to secure by Letters Patent of the United States is 1. A parachute provided with reinforcin cordswhich ass across the fabric and wit means where y the said cords are gripped to the parachute at its edges in a manner allowing of slip under excessive stresses on the fabric.

2. A parachute provided with reinforcin cords which pass across the fabric and a set of wide flanged eyelets secured around the edges of the fabric between the flanges of which eyelets the said cords are passed and are gripped to the fabric;

3. In a parachute as claimed in claim 2, a pair of washers between the gripping flanges of each of the said eyelets and receiv ng the cord and the fabric between them.

4. In a parachute, reinforcing cords passing across the fabric, a set of eyelets secured to the fabric at its edges and grippin the reinforcing cords at the periphery o the parachute, a second set of eyelets secured at the ends of the reinforcing cords, which extend beyond the first set of eyelets, and suspension cords passed through. the second set of eyelets.

5. A parachute provided with reinforcing cords extending acros the fabric and arranged in twov sets, an inner and an outer set, the outer set being secured to the parachute at the periphery and the inner and outer sets. interlacing with each other at their meeting points. Y

6. A parachute provided with reinforcing cords extending across the fabric and secured at the periphery of the parachute, suspension cords secured to the ends of the reinforcing cord and arranged in overlapping groups each passing through a connecting eyelet and a lower set of suspension lines to the upper ends of: which the said eyelets are secured, the lower suspension lines being connected at a point for the purpose of carrying the load.

7. A paper parachute provided with re inforcing strips secured on the paper fabric by a cementing composition which on dry ing is elastic and flexible, so that the flexibility of the material is not materially affected at such parts.

8. A. paper parachute provided with re inforcing strips secured on the paper fabric by a rubber solution.

9" A paper parachute in which all joints and reinforcing strips are secured by the means of a cementing composition which on drying is elastic and flexible.

10. A paper parachute as claimed in claim 7, coated over its surface with a Waterproofing film.

11. A paper parachute as claimed in claim 10, coated over its surface with a Waterproofing film of rubber solution.

OWEN DAVID LUCAS.

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