NZ247006A

NZ247006A - Disposable elapsed time indicator of laminated strip form: seal between reservoir and absorbent sponge is ruptured to activate indicator

Info

Publication number: NZ247006A
Application number: NZ24700693A
Authority: NZ
Inventors: Ian Anthony Birdling
Original assignee: Fourth Dimension Systems Ltd
Priority date: 1993-02-26
Filing date: 1993-02-26
Publication date: 1995-04-27

Description

<div class="application article clearfix" id="description"> Patents Form No 5 THE PATENTS ACT 1953 COMPLETE SPECIFICATION After Provisional Number: 247006 Dated: 26 February 1993 ELAPSED TIME INDICATOR DEVICE We, FOURTH DIMENSION SYSTEMS LIMITED, a New Zealand company of 8a Sheridan Terrace, Johnsonville, Wellington, New Zealand, hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement -1- - p. -ia- ELAPSED TIME INDICATOR DEVICE Field of Invention ; This invention relates to elapsed time indicator devices which, when activated by a user or supplier visually indicate elapsed time by way of start/finished markings or a calibrated display. The devices being of the kind which once activated cannot be normally stopped or retarded . r. operation until the prescribed time duration of the devices terminate, and if tampered with will become : r.e: rective and ;'or non-operable. Devices of this kind are capable of being employed for .5 a wide variety of uses or applications; and can be usefully employed as warning devices to indicate that such as packaged food or other products subject to deterioration should be used within a prescribed time after opening, or employed particularly in situations where a person is to be allotted or permitted a prescribed period of time (usually on payment of a fee) for doing some thing or such as the hire and use of equipment, articles or space eg as in the use of a vehicle parking space - in the latter case devices in accordance with the invention 25 may usefully and conveniently serve as a parking coupon or ticket issued and used in place of conventional parking meters and parking time ticket systems. Prior Art 30 There have been various prior proposals for elapsed time indicator devices, but most do not lend themselves to economic mass production methods and are thus not a cost effective substitute for existing restricted and/or elapsed 35 time indicator systems and display devices. And/or the prior elapsed time devices are often unreliable as far as reasonably accurate timing is concerned, particularly with a wide range of ambient temperature changes, and -2- tr.e device constructions generally, or the activating mechanisms or triggering arrangements therefor, may result m the devices being readily subject to failure in operation following activation and/or easily damaged or : accidentally and prematurely activated. The prior devices may also have a limited shelf life in the case of those employing chemicals in their construction, and/or where ineffective sealing takes place. 10 Objects of Invention An object of the present invention is to overcome the aforementioned disadvantages and shortcomings of the prior art devices; and to provide an alternative reliable elapsed 15 time indicator device which is accurate and effective in operation once activated, may be readily transported and stored for lengthy periods without deterioration, and is readily activated as required but without being prone to accidental or premature activation, or to failure 20 in activation. Another object of the invention is to provide a disposable elapsed time device indicator which is readily adapted to relatively low cost mass production, and a method and 2 5 means by which mass production of the devices can take place. Other and more particular objects and advantages of the present invention will become apparent from the ensuing 30 description. Summary of Invention According to a first aspect of this invention, there is 35 provided a disposable elapsed time indicator device comprising an at least partly laminated or wafer-like structure including a thin substantially flat base part with viewable spaced elapsed time indicator markings elongate transparent part disposed ir. juxtaposition witn said indicator markings and being of uniform cross section tnrcughout its ler.ctn, and said liquid contained in the reservoir being resistant to undue expansion and contraction over a prescribed temperature range, a separate compartment of said structure containing a liquid absorption means which is arranged to absorb liquid from said reservoir at a predetermined uniform rate when exposed tneretc, said compartment being initially scaled from said reservoir contents cut bemc adapted for communication tnerewith to expose the liquid to said absorption means for absorption tr.ereby at a predetermined rate or. opening of an outlet of said reservoir by user movable and operable activating means conjoining and arranged to rupture a seal at said cutlet; elapsed time being readable according to ar.c by direct comparison of the quantity of coloured liquid remaining m and,or evacuated from said reservoir elongate transparent part relative to said adjacent indicator markings. Preferably, the base part of the device is in the nature of an elongate thin flat strip of any suitable stable material such as a plastics, card, thin metal foil, or a plastjcised card or metal foil, with at least start and finisn time longitudinally spaced indicator markings provided on one face (the front) thereof for a fixed prescribed time device, or start/finish and intermediate time indicator calibrations can be provided; and the reservoir for the time display liquid is either in the form of an elongate trough formed in a transparent plastics cover strip extending over and laminated to said base part, or in tne form of an elongate clear plastics tube located between the cover strip and base part, with the trough or tube disposed and and sealed in position longitudinally on the front face side of the strip base 10 15 20 25 30 35 part adjacent and spanning the indicator markings. The liquid absorbtion means, which may be any suitable material, matrix or element of consistent porosity and density capable of absorbing liquid at a consistently uniform rate, is not limited in size or shape except insofar as it is preferably thin and substantially flat and is capable of absorbing at least the quantity of the liquid in the reservoir spanning the start and finish indicator markings; and may be located in a compartment defined by or provided on the rear side of the base part so as to have a part of the compartment and contained absorbtion means aligned with a defined outlet aperture through the base part at or near the finish indicator marking but initially sealed from communication with the liquid in the reservoir by seal means at said outlet aperture. The base part is preferably provided with a second defined aperture at or near the start indicator marking and arranged for the admission (on activation of the device) of atmospheric air to the reservoir to facilitate uniform evacuation of the contained liquid through the outlet on absorbtion by the absorbtion means; said atmospheric air aperture being initially sealed by seal means thereat, and rupturing or opening of both apertures at the start and finish markings is preferably arranged to be simultaneously effected by a common or linked movable activating means operable by a user or supplier of the device. The invention further includes the method(s) and mean(s) as herein described and by which the devices according to the two immediately preceding paragraphs can be manufactured. The Drawings Some preferred aspects of the invention will now be described by way of example and with reference to the ) accompanying drawings, in which: Figure 1 is a face view of a first ticket or coupon form of the device for use as a vehicle parking coupon; 5 Figure 2 is a longitudinal sectional view, as viewed in the direction of arrows II-II of figure 1 of the device with the components assembled and ready for use of the device before activation (the device is of exagerated -0 thickness for clarity only); Figure 3 is an exploded isometric view (partially diagrammatic) illustrating the first form of the device components prior to assembly; i 5 Figure 4 is a longitudinal sectional view (similar to figure 2) of an assembled second form of the device, as viewed in the direction of arrows IV-IV in figure 5, and 20 Figure 5 is an exploded view (similar to figure 1) of the components of a second form of the device, prior to assembly. Description 25 Referring firstly to figures 1 to 3 of the drawings, the parking coupon device is preferably in the form of a thin elongate laminated and sealed structure which can conveniently be in the region of about 100mm-300mm in 30 length and 15mm-50mm in width overall; but the device may of course be varied in size as required, and/or according to the intended use if other than for use as a parking coupon device. The device may be made up of three laminated components comprising a medial strip base 35 part 1 which can be fabricated from any suitable appropriate strength thin strip material eg a plastics or plasticised or foil material, an outer front cover strip 2 of a clear transparent thin but tough impermeable ?'' :'i o 6 c - a s ' i o rr. 3. ti ^ 11- s c n as cc _^y s ~ ■£: i~ 11 *. rr. in ~.. ■- - — g _ c n c: 5 0-5. rr.urcr.s :r.::.<r.ess eg a s^ira-le rr.avanai vculd be an ICI product such as a MELINEX 301 (registered trade mark) or a Du Pont product such as a MYLAR (registered 5 trade mark) or a polytetrafluoroethene (PTFE) or like plastics material,and a thin tough rear cover strip 3 again of any suitable tough impermeable material such as a plastics film strip. The rear cover strip 3 can be transparent or translucent, but is preferably not so 10 that inner working parts of the device as hereinafter described are not visible, and so that such rear cover strip can be printed thereon with such as advertising and/or instructions for use and/or disposal etc; a suitable material employed may be such as 20 micron thick PVDC 15 material, a MYLAR (registerd trade mark) MELINEX (registered trade mark) or similar material, but of course other materials having appropriate properties may be employed. 20 30 Tne base part 1 has its front face mar.Ked or calibrated to define at least start and finish time indicator markings 4,5 longitudinally spaced thereon, with intermediate time calibrations 4a if required, which are visible through the front cover strip 2 (or alternatively the time indicator markings can be printed on the inside or outside cf tne cover strip 2 preferably on tne inside so as to be protected against erasure or marring); and a longitudinally disposed elongate reservoir 6 containing a dark coloured liquid 7 clearly contrasting in colour to the colour of the base part 1 front face (at least in the vicinity of the indicator markings 4, 4a and 5 and reservoir 6) is arranged to span the start and finish markings 4,5, so that the time remaining or elapsed according to the device may be clearly visually ascertainable by a user or inspector or comparison of the coloured liquid 7 positioning relative to such indicator markings or calibrations 4,4a and 5. Tne reservoir 6 can in one construction be defined by y 35 an elongate shallow narrow and uniform cross section outwardly projecting trough 6a formed in the front cover strip 2 and sealed on the inner side by a thin impermeable membrane or foil strip 8 extending thereover and sealed 5 (after filling of the trough reservoir 6a with the liquid 7) at its periphery 8a to the inner face of the front cover strip 2 around the periphery of the formed trough 6a. The strip periphery 8a can be secured and sealed to the cover strip 2 by any suitable means, and for example 10 a hot melt adhesive such as a National Starch hot melt adhesive H580 and/or H556 in suitable proportions can be employed to effect a good permanent seal; or alternatively heat sealing or fusing techniques can be employed eg ultrasonic laser or other state of the art 15 plastics fusing and sealing means can be employed. The face of the strip 8 exposed to the liquid 7 and trough 6 is of a sharply contrasting colour to the colour of the liquid eg with a black, blue or red liquid 1, the exposed front face of the strip 8 can be white. 20 The liquid 7 may be of any suitable formulation that is economical to produce and may be an ink or alcohol and dye solution with appropriate additives enabling colour and characteristics retention over a long period of time, 25 and the ability to remain of substantially constant viscosity over a wide selected ambient temperature range eg a temperature range of between -20°C and +60°C. The liquid 7 must also be capable of being easily absorbed into a suitable absorbtion material or through a osmotic 30 filter as hereinafter described, and should also preferably be substantially non-toxic and unaffected by the composition of the materials of the device with which it is surrounded or in contact with. 35 On activation of the device the liquid in the reservoir 6 is arranged to gradually vacate from the reservoir with uniform absorbtion directly into a liquid absorbtion means or by way of an osmotic filter; and such liquid absorbtion means can be in the form of a thin compressed matrix material sponge or element 9 located and initially sealed within a compartment defined between the rear of the base part 1 and the rear cover strip 3. The material or element 5 9 is not limited in shape or size except that its absorbency capacity should preferably be at least 20-25% greater than that required to fully absorb the volume of liquid 7 in the reservoir 6 initially spanning the start and finish time markings 4,5; and the location of 10 the material or element 9 is such that a part overlaps the area of the end part (the lower end) of the seal strip 8 for the trough reservoir 6, but on the opposite rear side of the base part 1. 15 The base part 1 is provided with an aperture 10 at the said overlap area, and the strip 8 is provided with a first aligned sealed but rupturable liquid outlet opening 11 eg a preformed opening with a sealing material or membrane thereover or a weakened (partially scored or 20 perforated) opening periphery formed in the strip 8, and a second similarly formed opening 12 in the strip 8 at the opposite end of the reservoir 6. The first sealed opening 11 is of a predetermined size calculated to control the rate of flow of liquid therethrough (when ruptured 25 or opened) for absorbtion by the matrix or element 9, and thus the size of the first opening 11 can determine the intended duration of time for a particular coupon device; whereas the size of the second rupturable opening 12 on the strip 8 is not critical, as such second opening 30 12 is arranged to admit air to the upper end part of the trough rerservoir 6 to enable the liquid 7 to vacate such reservoir 6. Rupturing or opening of the two strip openings 11 and 12 is arranged to be effected such as by a user or provider of the device pulling a strong 35 linking element or member 13 (such as a length of thread, string, nylon filament on a thin elongate plastics strip) which is linked and secured at spaced points 13a to each seal portion covering the respective openings 11 and 12, and has an end portion 13b extending beyond the upper end of the device to enable gripping and pulling outwardly when required to simultaneously rupture or open the openings 11,12 and activate the device. The front cover 5 strip 2 and rear cover strip 3 are at least peripherally sealed to the base part 1, but a non-sealed or adhered elongate area or duct extends between the base part 1 and front cover strip 2 at the trough seal strip 8 and link element 13 to allow movement of the element 13 for 10 activation and air admission to opening 12. The base part 1 can be provided with a further aperture 14, of any convenient size or shape, which is in close proximity to the first aperture 10 and opens to the rear 15 compartment containing the absorbtion matrix or element 9, but is sealed on the front face side by the front cover strip 2 or a separate transparent seal over such aperture 14. This provides a sight aperture 14, located near the liquid outlet aperture 11 and aligned base part aperture 20 10 whereby initial liquid absorbtion by the matrix or element 9 is observable as a blooming thereon or thereof and a user will know that the device has been activated. Alternatively, at least a part of the matrix or element 9 at or near the area of the first outlet opening 11 can 25 be sightable from the rear of the device by way of a transparent part of the rear cover strip 3 so that blooming and activation is readily ascertainable. The absorbent matrix or element 9 can be a strip of 30 chromatography paper, blotting paper and/or a synthetic sponge material of polymer base or anything that is suitable for use as an absorbent matrix. If the material used is blotting paper it may be used to control the timing of the device by its makeup eg it can be a woodfibre 35 blotting paper of around 500-700 kg/m^ density, approximately 300 microns thick, and composed of 100% softwood fibres. It should have no fillers and it should be well beaten and refined to give a paper density of ■10- approximately 150 grams per square metre. Its moisture content must be limited to a maximum of 10%. Its fluid retention capacity should be around 25% greater than the volume of fluid required to be vacated from the reservoir D 6. By using different fillers (eg hardwood) the absorbency rate a blotting paper element 9 may be advanced and retarded, thereby creating the differentials for the coupon devices eg 30 minutes or 60 minutes. (A synthetic sponge material may be used to give the same results). The matrix 10 or element 9 should be able to breathe, ie the compartment in which it is contained should have a bleed hole to atmosphere allowing the trapped air in or between the matrix or element 9 and the liquid 7 to escape prior to the fluid and as the liquid 7 is taken up in the matrix 15 or element 9. The device is desirably provided with an attachment or mounting means suitable to its intended purpose; and can for example have the upper end of one of the main strip 20 parts 1,2 or 3, formed as an integral plastics clip portion or a projecting upper end part defining a tab which can be folded over for engagement with an upper edge of vehicle side window (wound down and then up). Alternatively, the tab 15 on a portion of the front or rear cover strips 25 2 or 3 can be provided with a non-permanent non-drying adhesive, protected by a peelable cover strip, for temporary adhesion to such as a vehicle windscreen (as a parking coupon device) or other surface. 30 Referring now to figures 4 and 5 of the drawings, in an alternative version of the elapsed time indicator device of this invention there are similarities in construction with the first described form, and the device can be of generally similar size and employ similar materials. 35 The device can again be in the region of 100mm300mm in overall length and 20mm-50mm in width with the medial base part 16 of thin rectangular strip form and manufactured from a suitable plastics or plasticised card 10 ,r foil material eg a 20-100 microns thick MYLAR, MELINEX 301, Polyvinylchloride or similar material - where a card or paper material is to be employed, it is preferable that it be plasticised or otherwise treated (after or before printing with the time indicator markings 4' and 5' and any other required or desired instruction and/or information) to render it liquid impervious. At least the area 16a over which the liquid reservoir 17 will clearly contrast. The front cover strip 19 is again of a transparent plastics material such as a polyester film in the region of 20 to 80 microns thick; or a MELINEX 301, MYLAR or PTFE type plastics or any similar plastics material of complementary 15 size and sealed at its periphery to be base part 16; and in this instance the reservoir 17 is defined by a separately formed uniform cross-section straw-like transparent plastics tube, which can for example be in the region of 80-100mm in length and 2-2.5mm in diameter 20 for a cylindrical tube, but which is preferably of flattened oval cross-section to reduce the overall thickness of the device and present a wider reservoir for improved viewing ot its content. The tubular reservoir 17 preferably has sufficient rigidity to be able to protect 25 its contents in transport and is located with a complementary dimensioned longitudinal trough 20 formed in the front cover strip 19 and arranged for disposition spanning the start and finish indicator markings 4',5'. The front cover strip 19 can also be provided with a dimple 30 or depression 21 at and connecting with a leadway to the lower end of the trough 20 and within which a small activating pellet 22 is located for use as later described. The straw-like reservoir 17 can be arranged to contain 35 in the region of 400-450 micro litres of the coloured liquid, but of course is not limited to the indicated exampled size and volumetric content. The liquid 18 for this and the first described form cf the device may be -12- an aqueous based liquid than is cheap and non toxic or may have solids such as inorganic salts dissolved into it which may extend the useful working ranges of the liquid. Alternatively, it may comprise glycols, glycol polymers, sugars or macrodextrans which will significantly change the properties of water; or the liquid 18 can be a mineral or vegetable oil of very light viscosity (a SAE 5 that has suitable viscosity) , and in the higher temperature coupon devices may be alloyed or mixed with alcohol or other such chemicals which will give it a suitable constant viscosity over a temperature range of approximately -15 to +60 degrees C. The straw-like reservoir 17 is sealed at one end 17a (its • ^ upper end) by a rupturable seal which has an end part of a monofilament nylon, strong cotton thread or like pull element 2 3 sealed therein eg by crimping and/or heat-sealing or plugging, with the remainder of the element 23 extending therefrom; and the opposite open lower end 20 17b of the reservoir 17 is hot melted into the lower end of the trough 20 in the front cover strip 19 so as to be fixed against movement or detachment. The liquid 18 within the reservoir 17 will not leak therefrom as it is held in the reservoir 17 by a combination of surface 25 tension and negative atmospheric pressure at the upper sealed end 17a. The base part 16 is provided with a lower aperture 24 which on assembly aligns with the front cover strip dimple 30 21 and pellet 22, and a strip or patch of a frangible material 25 such as a 15 micron aluminium foil is glued or heat sealed over the aperture 24 either on the front or rear side (preferably the latter) of the base part 16 to thus seal the pellet 22 within the dimple 21 and 35 reservoir open end 17b against exposure. And the base part 16 is provided with a further small aperture 23a aligned on assembly with the upper end of the trough 20 in close proximity to the upper end 17a of the reservoir . .'--1- o 23 car. extend tr.eretnrougn to l.tr.e case parr 16 and tr.e rear cover -; -c tn-u jpper er.d tnerecf, and provide an ; ar. 7•_™~r.1 w.-virecy pulling of sucr. pull element 23 witn . i.ir.a wr. list r.cldir.g tne lower end of tne device witn *-•••• w ill r-pt-r-.' cr cper. tne sealed upper end cf f-j :';5-;rvc:r 17 t; allow air admission to the reservoir r. -1 vler.er.t 23 car. simply extend from tne upper end : t..- d'.y..>j as ir. tr.e first described arrangement, but : ; : J f. :\t. and as illustrated it can be passed • . - ; ^.T.a 11 n.ci: 22a m tne base part 25 and is securec . • .s.- cy glueing to an elongate tab strip 27 whicn is ly located cetween the base part 16 and rear cover t. : r ^6 tc extend tnerefrcm. This provides an arrangement v;.v. :"'-i;y culling cf tr.e tab strip 27 effects pulling of ■"-11 element 23 tc open tne reservoir upper end 17a, .;u : 11. ur. provides an extended tab end 27a whicn can r^u-jG ever for location over tne upper edge of a vvr. side window in a parking coupon application, or as a fixing attachment tab in other applications. The exposed tab end 2 7a can be printed with appropriate instructions for use. Tr.e tab strip 27 can be manufactured from any suitable plastics cr other material of appropriate strength (eg a MYLAR cr MELINEX material of 20-40 microns thickness), and is located within an unsealed or substantially unsealed 30 longitudinally extending duct or compartment area 28 between the base part 1 and rear cover strip 26 (the tab strip 27 being narrower than both the base part 1 and rear cover strip 26, which are sealed at their edge parts; the inner end part 27b of the tab strip 27b is fixed 35 against movement such as by glueing, and an intermediate part 27c is initially folded in a Z-form as shown in the drawings to allow straightening for protrusion of the U The- duct cr ccir.psrtmer.t 28 fcr the tab strip 27 can aisc define cr extend ir.tc the compartment area 28a within which the absorbent maxtri.x cr element 29 (which may be fcrr.ed, as previously described, in thin flat strip fcrm from such as a chromatography paper, blotting paper or a synthetic spenge material) is located. Such compartment area 28a lies immediately behind the area 16a over which . j the strawlike tubular reservoir 17 and trough 20 are located, and the lever end cf such area 28a merges into a depression 20 which aligns with the base part aperture 24, front dimple 21 and contains a small hard bead or pellet 22; tc thus provide an arrangement enabling a user '.5 or supplier of the device to exert pressure on the dimple 21 (gripping the device end part between the thumb and first finger of one hand) to force the pellet 22 through and rupture the frangible strip or patch 25 simultaneously with pulling of the tab strip end 27a and attached pull element 23 with the other hand, to open the sealed upper end 17a of the reservoir, thereby activating the device and allowing the liquid 18 in the reservoir to pass through the base part aperture 24 for contact with and absorbtion by the absorbtion matrix or element 2 9 in the now 2 3 connecting compartment area 28a. The matrix or element 29 can be provided with an extended end portion 29a which projects into the depression area 30 behind the base part aperture 24 to initiate contact with the liquid 18 on first release from the reservoir lower end 17b. The duct 30 or compartment 28 within which the tab strip 27 is located also serves as an air duct for the compartment area 28a containing the absorbent matrix or element 29 to allow escape of air trapped in the dimple 21 and depression 30 ahead cf liquid reaching the matrix or element extended 35 portion 29, and escape of air from the compartment area 28a and matrix or element 29 as absorbtion takes place. A temporary readily broken seal can be provided at the cuter upper end cf the connecting strip duct or compartment 2b :c prevent the matrix or element 29 absorbing outside moisture whilst the device is stored or being transported and before properly activated as required on demand. In cne modification of the invention an osmotic filter m the form cf or associated with a semi-permeable membrane is employed in place of the previously described frangible strip cr patch 25 covering the base part aperture 24, and the pellet 22 is dispensed with. The osmotic filter ar.c membrane is net intended to be ruptured, and should re strong enough to resist this in handling, and the semipermeable nature will prevent leakage of liquid 18 from the reservoir 17 lower end 17b to the compartment area 28a and matrix or element extended end portion 29a, until activation by pulling the tab strip 27 and opening the reservoir 17 tc atmosphere. The rate of flow of liquid 18 through the base part aperture 24 would be controlled according to the make up of the filter membrane and exposed surface area at the aperture 24 ie a small area would retard flow and extend time, while a large area would speed flow and reduce time. As osmotic filter can be similarly applied at the base part aperture 22 in the construction described with reference to figures 2 and 3 of the drawings. Variation of the shape; density and/or composition of the absorbent matrix or element 9 or 29 can also result in different rates of absorbtion, and thus can be selected according to the prescribed or required time duration of the coupon device; and appropriate additives may be included in the composition to facilitate uniform absorbtion and/or to prevent release or leakage from the matrix or element 9 or 29. If blotting paper is employed as the absorbent material, it may be treated with a chemical trap such as an anhydrous sodium sulphate, which will prevent the liquid being released therefrom on expiry of the device after activation. The invention also includes methods of manufacturing and assembling the devices. For the constructions according to figures 2 and 3 plastics film strip of 250mm wide or thereabouts, for the formation of the front cover strips 2, is continuously passed over heated rollers which have the desired shape of the trough formed thereon to thus form the required trough permanently moulded into the continuous plastic film at prescribed intervals. Timing between the moulded trough impressions is critical to the rest of the coupon construction operations. On a separate feed roller system for production of the seal strips 8, aluminium (eg 15 micron thick) coloured foil in a continuous strip travels through rollers and the peripheries of openings 11 and 12 are partially punched with a perforator punch to provide sufficient perforations to effect a clean separation when pulled, and of a predetermined opening 11 size for the time duration of the coupon being made. The back of the foil strip 8 is then coated with a glue or adhesive film to seal the perforations, and is dried before an endless string 13 is cut and tack glued (hot melt) over the back of the strip, with each piece of glue at 13a on the string 13 coinciding with the location of the perforations for openings 11 and 12. The string 13 is cut to required length and the aluminium strip 8 is still in a continuous roll. The respective formed troughs 6 are sequentially filled with an exact measure of liquid 7, either by injection or by liquid sachet forming equipment. The foil strip 8 is passed over each filled trough 6 and cut. The film and foil strips 2 and 8 pass through a heated roller and are laminated together and entrap the liquid 7 in the trough 6. The next strip material for the production of the base parts 1 has been aluminised and pre screen printed. This continuous strip 1 is passed through an accurately timed hole punch to punch holes 10 and 14 sized according to coupon and time duration. . r.is s:n:- - is passed over a glue roller which has a masked cff segment in the middle, and strip 1 is heat rcllered tc the front cover strip 2; and is still left cr. as a continuous strip. Timing for the location of D the punched hole 10 over the seal strip opening 11 is critical, ana a puff of compressed air will keep the string 13 straight and off the glue face of base part strip 1. A continuous film of blotting paper/sponge or matrix of suitable absorbent material (of duration type for the ■lJ coupon being made) is glued on one side, but masked where r.cle 10 is sc as not to seal the surface contact; the absorbent paper or matrix/element 9 is heated rollered on to strip 1 and cut off accordingly, care being taken to only exceed hole 10 by just only 1 to 2mm on the string 15 side of the coupon. The last rear cover strip 3, which is preprinted as required, goes through a glue applying roller and then is layered over strips 1 and 9 and passed through heated rollers to ensure a flat coupon and that strip 3 is completely peripherally sealed around the 20 absorbent strip 9 (blotting paper, sponge, matrix system). In a method of manufacturing the coupon device of Figure 4 and Figure 5, the first step is to extrude tubular straw reservoirs 17 through the standard method of extruding 25 plastics tubing and straws. Each straw reservoir 17 is heated rolled into an oval shape crosssection, and the material used is preferably such that when the straw reservoir is cooled it remains fairly rigid. As the straw reservoir is pulled out of the extruder a continuous 30 monofilament element 23 of nylon or suitable material is pulled continuously through the straw reservoir 17 on an endless basis, and at the same time the coloured liquid 18 is injected into the reservoir 17. As the continuous reservoir forming straw or tube travels down 35 and is cooled off through the system, it is sealed at one end which severs the monofilament element 23 and entraps the liquid 18 in one end but does not trap the monofilament element 23 to the reservoir 17. As the - - b - '* monofilament: element 23 retracts from the straw reservoir 17, it is sealed at the opposite end before it exits fully, thus sealing the liquid 18 in with the monofilament element end. The monofilament element 23 is then cut to the " required length, as is the straw reservoir 17. Thus, a large number of straw or pretzels like filled reservoirs 17 can be produced with continuous operation, and prescribed numbers can be placed as a batch in a cartridge. This cartridge is then placed on another machine which -lJ allows the filled reservoirs 17 to be fired one at a time into a laminating machine of the main coupon. On the main machine a continuous approximately 200-250mm wide plastics film for the base parts 16 is preprinted and preglued on its faces, and is punched with holes 24 and 26 in an exact timed process for each coupon. On the same machine is an endless roll of plastics strip for the production of the front cover strip 19, which in turn travels round a heated roller and each trough 20 and dimple 21 is moulded into it on an exact time and spacing process. As the strip 19 is drawn out flat, a preformed and prefilled reservoir 17 with a string 23 in it is fired from the cartridge into the respective trough 17 and hot melted at the dimple end 21 and thus sealed in there. A pellet 22 is then dropped into dimple 21 and retained 25 in there by a little blob of glue or something similar. As laminate strip 19 and laminate 16 are drawn together and sandwiched on top of each other, prior to being sandwiched the straw or pretzel like filled reservoir 17 is punctured at the pellet 22 end with a needle or 30 the like. The liquid 18 should not escape from the reservoir 17 due to surface tension and the fact that the opposite end is closed to atmospheric pressure. Strips 19 and 16 subsequently drawn together and heat sealed to become one. 35 On another roll there is an aluminium foil strip approximately 20mm wide (for forming the frangible strips or patches 25) which is preglued and passed over strip 16 (cut to size) so as to cover each hole 24, thus sealing a reservoir and pellet in the respective trough 17 and dimple 21. The aluminium foil strip or patches 25 are sealed in position. 5 A point to note here, is that when each straw or pretzel like reservoir 17 is fired in position into the respective trough 20, the string or monofilament element 23 is pushed through hole 23a in the base part 16. On a separate 10 roller, strip material 27 is fired into position between the strips 16 and 26, is heat sealed at the inner end and folded and pressed down as shown in figures 4 and 5. The monofilament element 23 is then hot melt fixed to strip 27. Strip 26 is a continuous plastics film again 15 of approximately 200-250mm wide, and is passed around heated rollers where duct or compartments areas 28 and 28a and dimple 30 are premoulded into the strip 26, this again requiring exact timing for correct spacing between each impression. On this continuous strip 26 is inserted 20 and glued the matrix or element 29, suitably sealed around depression 30, with a breather tube for the system built in to the matrix or element 29 or being defined by the duct or compartment areas 28 and 28a. 25 Finally, the rear cover strip 26 is laminated to strips 16 and 19 and heat sealed, thus completing the coupon devices; which can be individually separated at the time or remain as a continuous band or strip of say 10 to 100 coupon devices, or rolled onto a roller suitable for 30 distribution. The invention has been particularly described with reference to a straight elongate liquid reservoir and this construction is particularly suitable for relatively 35 short duration elapsed time indicators. However, lengthier time durations can be provided for without increase or with minimal increases in the overall size of the coupon devices by presenting and fixing the liquid filled reservoir ir. s - cr. as a :_"-snape or S-snace fcrrr.. Seme preferred aspects cf the invention nave been described and illustrated by way of example ana with reference tc the accompanying drawings, but it will be appreciated tnat ether variations cf and modifications tc tne invention and its applications can be made without departing therefrom. As previously indicated, the invention is net confined to a vehicle parking coupon application. 10 . 3 20 30 35 </div>

Claims

<div class="application article clearfix printTableText" id="claims"> 2470 WHAT WE CLAIM IS: 1. A disposable elapsed time indicator device comprising an at least partly laminated cr vaier-li^e structure including a tnir. substantially flat base part wit r. viewable spaced elapsed time indicator markings tr.ereon, a liquid reservoir containing a coloured liquid contrasting in colour tc that of said base part at said indicator markings, said reservoir navmg at least an elongate transparent part disposed in juxtaposition with said indicator markings and being cf uniform cross section tnroughcut its ler.gtn, and sard liquid contained in tne reservoir being resistant tc indue expansion and contraction over a prescribes temperature range, a separate compartment of said structure containing a liquid absorption means which is arranged to absorb liquid from said reservoir at a predetermined uniform rate when exposed thereto, said compartment being initially sealed from said reservoir contents but being adapted for communication therewitn to expose the liquid to said absorption means for absorption thereby at a predetermined rate on opening of an outlet of said reservoir by user movable and operable activating means conjoining and arranged to rupture a seal at said outlet; elapsed time being readable according to and by direct comparison of the quantity of coloured liquid remaining in and/or evacuated from said reservoir elongate transparent part relative to the adjacent indicator markings. 2. A device according to claim 1 wherein the base part of the device is in the nature of an elongate thin flat strip of any suitable stable material. 3. A device according to claim 2 wherein the base part is formed from either plastics, card, thin metal foil, plasticised card or metal foil. 4. A device according to any one of claims 1 247006 tc j wr.erem .eas: s: art ana rir.isn time longitudinally spaced indicator markings are provided cr. one race thereof fcr a fixed c^-^scribed tune device 5 . A device according tc any one of claims 1 tc 3 wnerein start/finish and intermediate time indicator calibrations are provided. 6. A device according to any one of the preceding claims wherein the reservoir for the time display liquid is eitner in the form cf an elongate trough formed m a transparent plastics cover strip extending over and laminated to said base part, or m the form cf ar. elongate clear plastics tube located between the cover strip and base part, with the trough or tube disposed ar.d sealed in position longitudinally on the front face side of the strip base part adjacent and spanning the indicator markings. 7 . A device according to any one of the preceding claims wherein the liquid absorption means comprises a material, matrix or element of consistent porosity and density capable of absorbing liquid at a consistently uniform rate. 8. A device according to claim 4 or claim 5, or claim 6 or claim 7 when dependant on claim 4 or claim 5,wherein the liquid absorption means is not limited in size or shape except insofar as it is thin and substantially flat and is capable of absorbing at least the quantity of the liquid in the reservoir spanning the start and finish indicator markings. 9. A device according to claim 4 or claim 5, or any one of claims 6 to 8 when dependant on claim 4 or claim 5, wherein the liquid absorption means is located in a compartment defined by or provided on the.'"' rear side of the base part so as to have a part '/of the compartment and contained absorption means aliened with a defined outlet aperture through the base \ ' L *4 J ... A aevioe iccc ramg t 2 c.a; ~ - wneriin tne base- psr: is provided w::;. 5 second defined aperture at cr near the start indicator marking and arranged for tne admission (en activation cf the device; cf atmcspr.enc air tc the reservcir tc facilitate uniform evacuation cf the contained liquid tnrough the cutlet :r. abscrctior. bv tne absorotior. means . a tmcspneri o air aperture is initially sealed by seal means thereat, and rupturing or opening of both apertures at the start and finish markings is arranged to be simultaneously effected by a common or linked movable activating means operable by a user or supplier of tne device. 12. A device according tc any one cf the preceding claims navir.g dimensions cf 10Oram-300mm in length and 15mm-5 0mm m width overall. 12. A device according to any one cf the preceding ..•ia:ms having an outer front cover strip of a clear transparent thin but tough impermeable plastics material m the region of 50-80 microns thickness. 14. A device according to any one of the preceding claims having a rear cover strip which is transparent cr translucent. 15. A device according to claim 14 wr.erein the rear cover strip can be printed tnereon with advertising anc-or instructions for use and/or disposal. 16. A device according to claim 1 wherein the 2* base part has its front face mar.-:-id c r calibrated tc define start and fir.isr. time indicator markings longitudinally spaced thereon, with intermediate time calibrations which are visible tnrough a transparent front cover strip, or alternatively the time indicator markings can be printed on the inside of the cover strip so as to be protected against erasure or marring, and a longitudinally disposed elongate reservoir containing a dark coloured liquid clearly contrasting in colour to the colour of the base front face, at least in the vicinity of the indicator markings, and the reservoir, is arranged to span the start and finish markings so that the time remaining or elapsed according tc the device may be clearly visually ascertainable by a user or inspector for comparison of the coloured liquid positioning relative to such indicator markings or calibrations. 17. A device according to any one of the preceding claims wherein the liquid is of a formulation having appropriate additives and characteristics enabling colour retention over a long period of time, and the ability to remain of substantially constant viscosity over a temperature range of between -20°C and +60°C. 18. A device according to claim 17 wherein the liquid is also capable of being easily absorbed into a suitable absorbtion material or through a osmotic fiIter. 19. A device according to claim 17 wherein the liquid is substantially non-toxic and unaffected by the composition of the materials of the device with which it is surrounded or in contact with. 20. A device according to claim 7 when dependant on claim 4 or claim 5, or according to claim 8 or clairfTt <P'^u A. \ 9, wherein the liquid absorption means has an absorbrfhdy 24/006 capacity cf at least 23-25^ greater than tnat required tc fully abscrb tne volume of liquid m the reservoir initially spanning the start and finish time markings. 21. A device according to claim 20 wherein the locaticn of the liquid absorption means is such that a part overlaps the area of the outlet part and seal for the trough reservoir, but on the opposite rear side of the base part. 22 . A device according to claim 20 wherein the liquid absorption means is a strip of chromatography paper and/or blotting paper and/or a synthetic sponge material of polymer base. 23. A device according to claim 22 wherein if the material is blotting paper it can be used to control the timing of the device by its makeup. 24 . A device according to claim 22 wherein the blotting paper comprises a woodfibre blotting paper 3 of 500-700 kg/m density, approximately 300 microns thick, and composed of 100% softwood fibres. 25. A device according to claim 24 wherein the blotting paper has no fillers and is well beaten and refined to give a paper density of approximately 150 grams per square metre. 26. A device according to claim 25 wherein the moisture content of the blotting paper is limited to a maximum of 10% by weight. 27. A device according to claim 23 wherein different fillers are used to control the absorbency rate. /•.<wTO \ 28. A device according to any one of the precercking ^ L V ^ V f r LM U claims further comprising an attachment or mounting means suitable tc its intended purpose. 29. A device according to claim 28 wherein the mounting means comprises the upper end of one of the main strip parts formed as an integral plastics clip portion or a projecting upper end part defining a tab which can be folded over for engagement with an upper edge of vehicle side window. 30. A device according to claim 28 wherein the mounting means comprises the tab on a portion of the base part cr a cover strip therefor; the tab being provided with a non-permanent non-drying adhesive, protected by a peelable cover strip, for temporary adhesion to such as a vehicle windscreen or other surface. 31. A device according to claim 1 wherein the reservoir is defined by a separately formed uniform cross-section straw-like transparent plastics tube. 32. A device according to claim 31 wherein the tube is in the region of 80-100mm in length and 2-2.5mm in diameter for a cylindrical tube, but which is of flattened oval cross-section to reduce the overall thickness of the device and present a wider reservoir for improved viewing of its content. 33. A device according to claim 31 wherein the tube reservoir has sufficient rigidity to be able to protect its contents in transport and is located within a complementary dimensioned longitudinal trough formed in a front cover strip and arranged for disposition spanning start and finish indicator markings on the device. 34. A device according to claim 33 wherein front cover strip is provided with a dimple^ or 1 f C w I * depression at and connecting with a leadway tc the reservoir outlet part of the trough and within which dimple or depression a small activating pellet is located. 35. A device according to claim 31 or claim 32 wherein the straw-like reservoir is arranged to contain in the region of 400-450 micro litres of the coloured liquid. 36. A device according to any one of the preceding claims wherein the liquid is an aqueous based liquid that is non-tcxic and can have solids such as inorganic salts dissolved into it which may extend the useful working ranges of the liquid. 37. A device according to any one of claims 1 to 35 wherein the liquid comprises glycols, glycol polymers, sugars or macrodextrans which will significantly change the properties of water, or the liquid can be a mineral or vegetable oil of very light viscosity, and/or may be alloyed or mixed with alcohol or other such chemicals which will give it a suitable constant viscosity over a temperature range of approximately -15 to +60 degrees C. 38. A device according to claim 34 wherein the straw-like reservoir is sealed at one end by a rupturable seal which has an end part of a monofilament nylon, strong cotton thread or like pull element sealed therein by crimping and/or heat-sealing or plugging, with the remainder of the element extending therefrom and wherein the opposite open end of the reservoir is hot melted into the reservoir outlet part of the trough in the front cover strip so as to be fixed against movement or detachment. 39. A device according to claim 38 wherein tjife base part is provided with a lower aperture which/.<3'n assembly aligns with the front cover strip dimple land pellet, and wherein a strip or patch of a frangible* 24 / 0 -23 - material sucn as a 15 micron aluminium foil is glued or heat sealed over the aperture either on the front or rear side of the base part to both seal the pellet within the dimple and seal the reservoir open end against exposure. 40. A device according to claim 39 wherein the base part is provided with a further small aperture aligned on assembly with the upper end of the trough in close proximity to the upper end of the reservoir so that the pull element can extend therethrough to a position between the base part and the rear cover strip at the upper end thereof, and provide an arrangement whereby pulling of such pull element with one hand whilst holding the lower end of the device with the other will rupture or open the sealed upper end of the reservoir to allow air admission to the reservoir. 41. A device according to claim 40 wherein the pull element passes through said further small aperture in the base part and is secured such as by glueing to an elongate tab strip which is slidably located between the base part and rear cover strip to extend therefrom. 42. A device according to claim 22 wherein a temporary readily broken seal is provided at an outer part of the liquid absorption means compartment to prevent the absorption means absorbing outside moisture whilst the device is stored or being transported and before properly activated. 43. A device according to claim 38 wherein an osmotic filter in the form of or associated with a semi-permeable membrane is employed to prevent leakage of liquid from the reservoir lower end to the compartment area and a liquid absorption means extencWjS. t end portion until activation by pulling the tab 3%?ip and opening the reservoir to atmosphere. ( CH ! U rate cf flew cf liquid tnrough th-_- reservoir cutlet is controlled according to tne make up of the filter membrane and exposed surface area cf the filter membrane at said outlet. 45. A method of manufacture cf the device cf any one of claims 12 to 26 comprising the steps of: a) forming the front cover strip by continuously passing a plastics film strip over heated rollers which have the desired shape of the trough formed thereon to thus form the required trough permanently moulded into the continuous plastic film at prescribed intervals; b) on a separate feed roller system for production of the seal strips, aluminium coloured foil in a continuous strip is passed through rollers and the peripheries of openings are partially punched with a perforator punch to provide sufficient perforations to effect a clean separation when pulled, and of a predetermined opening size for the time duration of the coupon being made; c) the back of the foil strip is then coated with a glue or adhesive film to seal the perforations, and is dried before an endless string is cut and tack glued over the back of the strip; d) the string is cut to required length and the aluminium strip is still in a continuous roll; e) the respective formed troughs are sequentially filled with an exact measure of liquid, either by injection or by liquid sachet forming equipment; f) the foil strip is passed over each filled trough and cut; g) the film and foil strips pass through a heated roller and are laminated together with entrap the liquid in the trough; h) the next strip material for the production of the base parts has been aluminised and pre-screen printed; >=•', /*> 247006 i) this continuous strip is passed through an accurately timed hole punch to punch holes sized according to coupon and time duration; j) this strip is passed over a glue roller which has a masked off segment in the middle, and is heated rollerea to the front cover strip; and is still left on as a continuous strip; k) a continuous film of blotting paper/sponge or matrix of suitable absorbent material (of duration type for the coupon being made) is glued on one side; 1) the absorbent material is heated rollered on to the strip and cut off accordingly; and, m) the last rear cover strip which is preprinted as required, goes through a glue applying roller and then is layered over the strips and passed through heated rollers to ensure a flat coupon and that strip is completely peripherally sealed around the absorbent strip. 46. A method of manufacturing the device of any one of claims 26 to 44 comprising the steps cf: a) extruding tubular straw reservoirs through the standard method of extruding plastics tubing and straws, such that each straw reservoir is heated rolled into an oval shape cross-section, and the material used is such that when the straw reservoir is cooled it remains fairly rigid; b) as the straw reservoir is pulled out of the extruder a continuous monofilament element of nylon cr suitable material is pulled continuously through the straw reservoir on an endless basis, and at the same time the coloured liquid is injected into the reservoir; c) as the continuous reservoir forming straw cr tube travels down and is cooled off through the system, it is sealed at one end which severs the monofilament element and entraps the liquid one end but does not trap the monofilament element to the reservoir; / " <r- d; as the monofilament element retracts from the straw reservoir it is sealed at tne opposite end before it exits fully, thus sealing the liquid in with the monofilament element end; e) the monofilament element is then cut to the required length, as is the straw reservoir; f) a plastics film for the base part is pre-printed and pre-glued on its faces, and is punched with holes and in an exact timed process, further an endless roll of plastics strip for the production of the front cover strip travels round a heated roller for moulding a trough and dimple; g) as the strip is drawn out flat, a pre-formed and pre-filled reservoir with a string in it is placed into the respective trough and hot melted at the dimple end and thus sealed in; h) a pellet is then dropped into dimple and retained by glue; i) as laminate strips are drawn together and sandwiched on top of each other, prior to being sandwiched the filled reservoir is punctured at the pellet end with a needle or the like; and, j) the strips are subsequently drawn together and heat sealed to become one. 47. A device according to claim 1 wherein the liquid reservoir is an U-shape or S-shape form. 48. A device according to any one of claims 1 to 44 constructed and arranged to be suitable for vehicle parking coupon application. 49. A device substantially as herein described or exemplified with referecne to the accompanying drawings. 50. A method according to claim 45 or 46, substantially as herein described or exemplified. 51. A method of manufacturing the device of any one of claims 1 to 44 cr 47 or 48, substantially as herein described or exemplified. FOURTH DIMENSION SYSTEMS LIMITED By Their Authorised Attorneys JOHN A REMMINGTON & ASSOCIATES ^'1 '"p' : / / /—L ./K la- \{ </div>