US3292680A

US3292680A - Buoyant key case

Info

Publication number: US3292680A
Application number: US514064A
Authority: US
Inventors: Douglas J Broughton
Original assignee: Buxton Inc
Current assignee: Buxton Inc
Priority date: 1965-12-15
Filing date: 1965-12-15
Publication date: 1966-12-20
Anticipated expiration: 1983-12-20
Also published as: GB1109249A; CH450642A; ES333371A1; BE689266A; DE1532832A1; FR1499049A

Description

1966 I D. J. BROUGHTON 3,

BUOYANT KEY CASE Filed Dec. 15, 1965 2 Sheets-Sheet 1 INVENTOR.

DOUGLAS 1 BROUGHTON BY 41d Dec. 20, 1966 D. J. BROUGHTON BUOYANT KEY CASE 2 Sheets-Sheet 2 Filed. Dec. 15, 1965 INVENTOR. DOUGLAS l. EIROUGHTON BY t 1 -41. 4 meal Custom United States Patent M 3,292,680 BUOYANT KEY CASE Douglas J. Broughton, Springfield, Mass., assignonto Buxton, Incorporated, Agawam, Mass., a corporation of Massachusetts Filed Dec. 15, 1965. Ser. No. 514,064 6 Claims. (Cl. 150-40) This invention relates to key cases, in particular buoyant key cases.

In recent years outdoor activities have rapidly increased in popularity and in ever increasing numbers people have turned to water sports as a prime source of enjoyment. For example, there are millions of people every year who enjoy boating in one form or another, and, of course, fishing as well as other water sports.

Water sportsmen, like most other people, are usually burdened with keys for various purposes, such as car keys, boat keys, house keys, etc. In todays highly mobile population, the water sportsman usually drives his car to and from the water where he engages in his recreation. If during the day, he accidentally loses his keys in the water, it means a great deal of time and effort in attempting to locate and retrieve the keys with the likelihood being failure. The loss of the keys means that the sportsman is faced with the unpleasant situation of a locked car and/or a locked house. With this in mind, I have developed a light, compact and flexible buoyant key case for use by water sportsmen.

Therefore, an object of this invention is to provide a key case which when filled with a full complement of keys will float in water.

Another object is to provide a key case buoyant in nature and of such constructional characteristics as to be easily fabricated and manufactured.

A further object of this invention is to provide a key case as described above that is not only buoyant, but also pleasing in appearance and of convenient size so as to be easily carried about.

A still further object of this invention is to provide a buoyant key case as described above that is flexible, compact and comfortable, for pocket carrying in the same manner as the user would carry a non-buoyant key case.

Other objects and advantages of this invention will become more apparent from the following description, which is to be considered together with the accompanying drawings, in which:

FIG. 1 is a perspective view of a key case embodying this invention with a section broken away;

FIG. 2 is a top view of the case as shown in FIG. 1;

FIG. 3 is a perspective view of the case while open with sections broken away;

FIG. 4 is a plan view of the case in open condition and with the liner cut away to show the constructional characteristics of the case;

FIG. 5 is a plan view similar to FIG. 4; and

FIG. 6 is a sectional view substantially on line 6-6 of FIG. 5.

Referring to the drawings, 10 designates the key ease generally. In FIGS. 1, 2, and 3 it will be clearly noted that the case is comprised of a back portion 12 with right and

left closure flaps

14 and 16 respectively hinged to the side edges of the back portion 12. As shown, the right or outer closure flap 14 carries the socket 18 of a snap fastener assembly 20, while the left closure flap carries the post (not shown) of the fastener assembly 20.

A flap 22 is provided in hinged relation to the back portion 12 of the key case 10. On this flap is carried key retaining means 24 which supports key loops 26 for keys, such as shown at 28.

3,292,680 Patented Dec. 20, 1966 The key case 10 is composed of three sheets, a cover sheet 30, a liner sheet 32 and a unitary sheet of unicellular buoyant material 34 disposed between the cover and liner sheets.

It will be noticed, that the cover sheet 30 and the liner sheet 32 are both unitary sheets and that upon fabrication together with the buoyant sheet 34, they form the back portion 12 and the right and

left closure flaps

14 and 16 respectively of the key case 10.

The hinging action between the back portion 12 and the

closure flaps

14 and 16 is secured by the flexible character of the material and by lines of fold 35 formed by the action of a sealing die through hinging

sections

36 and 38 of the key case 10, as seen in FIGS. 1, 3, and 5.

The material used for the cover sheet 30 and the liner sheet 32 should be soft, pliable or flexible, and preferably water impervious, such as a synthetic plastic sheet material, for example, a vinyl compound or the like. For maximum buoyancy and ease of closing the assembled key case, it has been found that the cover 30 should have a gauge thickness of from about .012 inch to .015 inch, while the liner 32 should be somewhat thinner with .a gauge thickness of about .008 inch to .012 inch. A good combination is the cover at .015 inch thickness with the liner at .012 inch.

In order to impart the buoyant character to the key case, the sheet of cellular buoyant material 34 is disposed between the cover 30 and the liner 32 before the two are joined together. The unicellular sheet 34 is preferably soft and pliable, and when combined with the

sheets

30 and 32 provides a padded or cushion effect, but is of sufficient stiffness to give good form to the case. It will be observed in FIG. 4, that the sheet 34 is of one piece construction with the

cutouts

40, 42 and 44 being cut away to accommodate the hinging action of the case itself and the key case snap fastener 20 respectively.

As shown in FIG. 4, the

cutout sections

40 and 42 terminate inwardly of the upper and lower edges of the buoyant sheet 34, leaving bridging sections 46. The bridging sections 46 permit ease of assembly of the sheet of buoyant material 34 with the cover sheet 30 and the liner sheet 32, while the

cutouts

40 and 42, which register with the

hinging sections

36 and 38, allow the cover sheet 30 and the liner sheet 32 to be sealed together to form the hinged relation between the back portion 12 and the closure flaps 14 and 16 of the key case 10.

Even though the actual size of the key case is not limited in this invention, it is dependent in part upon the volume of the buoyant material that must be used to float support a specific number of keys.

In the particular key case shown in the drawings, wherein the key case comprises a cover 30 and a liner 32. a snap fastener assembly 20, a key retaining means 24 and six standard uncut keys, the total weight that needs to be float supported is generally from about 68 to 74 drams. I have found that approximately 4.0 cubic inches of a buoyant material with a buoyancy factor of 55 to pounds/cu. ft. is required to float support the above described case in Water.

Therefore, the volume of buoyant material to be used must be capable of float supporting a specific number of keys depending on key case design and in turn the key case volume may be adjusted accordingly to accommodate such a volume of buoyant material. This amount of buoyant material will hereinafter be referred to as a float supporting amount.

In accordance with this invention, I have found that for purposes of general appearance and convenience of size, the float supporting amount of buoyant material should be in sheet form, preferably unitary, with a thickness of from about /8 to inch, preferably about inch.

With this as the case, the volume involved in relation to float supporting amounts of buoyant materials may be adjusted by changing the length and width of the buoyant material and, of course, adjusting the dimensions of the cover and liner accordingly. However, to some extent the width and length of the key case also have limits. This limitation is controlled by practicability of design. In other words, for practical purposes of carrying the key case about, it must fit comfortably in the usual size clothes pocket.

As to the buoyant material itself, it may be any one of a number of unicellular foam materials, such as polyethylene, polystyrene, polyurethane, etc. In the preferred embodiment of this invention, a flexible polyethylene foam manufactured under the trade name Ethafoam by the Dow Chemical Company, Midland, Michigan, is used. Ethafoam has a density of about 2.0 pounds/ft. and a buoyancy factor of more than 55 pounds/ft. This This along with a water absorption of less than 1.0% by volume makes it an ideal material for application in this invention.

As is clear, the primary purpose of the buoyant material is to float support the key case and keys disposed therein. However, there is a secondary purpose which should be kept in mind when choosing the buoyant material. The material must not only act as buoyant matter, but must also act as a stiffener for the various compartments of the key case. Yet, there must be a balance between its stiffening properties and its flexibility properties, otherwise the key case will not be suitable to be carried around in a clothing pocket.

The fabrication of the buoyant key case is simple and efficient. In essence, the liner sheet 32 is placed with its outside surface facing downwardly. Next an adhe sive coating may be applied to one or the other or both of the surfaces of the cellular material or liner. This is followed by the positioning of the unitary sheet of the cellular material 34 on the liner 32 to which itadheres. This step is used to align the buoyant material 34 between the liner sheet 32 and the cover sheet 30 so as to permit proper heat sealing of the two sheets without adversely affecting the buoyant material 34.

After the buoyant cellular material 34 is disposed on the liner sheet 32, the cover sheet 30 is placed over same, and the two sheets are sealed together by appropriate means, such as heat sealing or cementing, about the perimeter of the key case and along the lines of fold 35 through the hinging

sections

36 and 38. In the sealing operation, care must be taken not to crush the cellular foam material as this will adversely affect its buoyancy properties by driving out pocketed air. With this problem in mind, the cover sheet 30 and liner sheet 32 are purposely made oversize as compared to the cellular sheet material, thereby leaving a free edge for sealing purposes, see FIG. 4.

Once the sealing operation is completed, the key case itself is a water-tight chamber. As the unicellular foam used accommodates essentially all space between the cover sheet 30 and the liner sheet 32,'should either cover or liner sheet be perforated the amount of water admitted by the perforation will not substantially affect the buoyancy of the key case as unicellular foams have a very low water absorption capacity as well as very low capillarity.

Finally, upon the complete sealing of the cover 30 to the liner 32, the flap 22 is provided in hinged connection with the back member 12 of the key case 10 with suitable means 24 for supporting keys 28. In general, the flap 22 is of two piece construction, the first piece being a rigid body upon which is superimposed a vinyl covering with a gauge thickness of about .012 to .015 inch. These two parts are sealed together and in turn both are hinge sealed to the back member 12 of the key case 10.

The key supporting mean-s 24 which is attached to the flap 22 may take any desired form, that shown being more fully disclosed in the patent to Harvey No. 2,582,037 issued on January 8, 1952. Preferably, the key supporting means 24 includes a rigid bar member extending transversely of the case, such means being provided, in the key supporting means shown, by the metal cylinder 48 to which the individual key retaining loops 26 are attached.

Although the invention has been particularly shown and described, his contemplated that various changes and modifications may be made without departing from the scope thereof as indicated by the following claims.

Having thus described the invention, what is claimed is: 1. A buoyant key case comprising a pair of unitary moisture impervious sheets, a unitary sheet of unicellular buoyant material disposed between said moisture im-' closure flaps comprisinga unitary moisture impervious 7 cover sheet, a unitary moisture impervious liner sheet, said cover sheet having a thickness greater than the thickness of said liner sheet, a unitary sheet of unicellular buoyant material with cut-outs therein disposed between said cover sheet and said liner sheet and key retaining means disposed on the back member of said key case,

said cover sheet and said liner sheet being sealed together about their periphery forming at least one water-tight compartment and also being sealed together through said cut-outs thereby forming hinges between said back mem-.

her and closure flaps.

3. Buoyant key case as set forth in claim 2 wherein the thickness of the cover sheet is from about .012 inch to .015 inch and the thickness of said liner sheet is from.

about .008 inch to .012 inch.

4. Buoyant key case as set forth in claim 3 wherein said unitary'sheet of unicellular buoyant material is a polyethylene foam, and said cover and liner sheets are sheet vinyl plastic.

5. Buoyant key case as set forth in claim 4 in which said cut-outs are disposed in spaced parallel relation perpendicular to the upper and lower edges of said case,

said cut-outs terminating inwardly of said upper and lower edges to leave bridging portions interconnecting the portions of said unicellular sheet within the back member and closure flaps of said case.

6.- Buoyant key case comprising a unitary moisture impervious vinyl cover including a back member with closure flaps hinged to the side edges thereof, a unitary moisture impervious vinyl liner including a back member with closure flaps hinged to the side edges thereof, key

retaining means disposed in saidkey case, a float supporting amount of a' unicellular buoyant sheet material sealed between said cover and said liner sheet, said amount being capable of float supporting said key case with a full complement of keys disposed on said key retaining means.

References Cited by the Examiner UNITED STATES PATENTS 2,051,432 8/1936 Zahn 40 2,661,785 12/1953 Daust 150-28 2,667,198 1/1954 Klein 150 2.1 2,795,258 6/1957 Berry et al. 150-28 2,837,132 6/1958 Daust 150--28 FRANKLIN T. GARRETT, Primary Examiner.

Claims

1. A BUOYANT KEY CASE COMPRISING A PAIR OF UNITARY MOISTURE IMPERVIOUS SHEETS, A UNITARY SHEET OF UNICELLULAR BUOYANT MATERIAL DISPOSED BETWEEN SAID MOISTURE IMPERVIOUS SHEETS AND HAVING CUT-OUTS THEREIN, KEY RETAINING MEANS DISPOSED IN SAID KEY CASE, SAID MOISTURE IMPERVIOUS SHEETS BEING SEALED TOGETHER ABOUAT THEIR PERIPHERY FORMING AT LEAST ONE WATER-TIGHT COMPARTMENT AND ALSO BEING SEALED TOGETHER THROUGH SAID CUT-OUTS IN SAID SHEET OF BUOYANT MATERIAL FORMING HINGED CLOSURE FLAPS.