TECHNICAL FIELD

The present invention pertains to a bus stop shelter.

BACKGROUND OF THE INVENTION

Bus shelters are known in the art. Bus stop infrastructure ranges from a simple pole and sign to a rudimentary shelter, to sophisticated structures. The usual minimum is a pole mounted flag with a suitable name or symbol. Bus stop shelters known in the art may have a full or partial roof, supported by a two, three or four sided construction. Modern stops are usually mere steel and glass/perspex and/or glass fiber constructions, although in other places, such as rural areas, bus stop shelters may be wooden or brick built. The construction may include small inbuilt seats. The construction may feature advertising, ranging from simple posters to complex illuminated, changeable or animated displays. Some installations have also included interactive advertising. Design and construction may be uniform to reflect a large corporate or local authority provider, or installations may be more personal or distinctive where a small local authority such as a parish council is responsible for the bus stop and the associated shelter. The bus stop shelter may include separate street furniture such as a bench, lighting and a garbage receptacle.

Individual bus stop shelters may simply be placed on the sidewalk next to the roadway, although they can also be placed to facilitate use of a bus-way. More complex installations can include construction of a bus turnout or a bus bulb for traffic management reasons, although use of a bus lane can make these unnecessary. Several bus stops may be grouped together to facilitate easy transfer between routes. These may be arranged in a simple row along the street, or in parallel or diagonal rows of multiple stops. Groups of bus stops may be integral to transportation hubs. With extra facilities such as a waiting room or ticket office, outside groupings of bus stops can be classed as a rudimentary bus station.

Most bus stops are identified with a metal sign attached to a pole or light standard. Some stops are plastic strips strapped on to poles, and others involve a sign attached to a bus shelter. The signs are often identified with a picture of a bus and/or with the words bus stop (in English speaking countries). The bus stop flag will sometimes contain the route numbers of all the buses calling at the stop, optionally indicating frequent, infrequent, 24 hour, and night services. The flag may also show the logo of the dominant bus operator or the logo of a local transit authority with responsibility for

bus services in the area. Additional information may include an unambiguous name for the stop and the direction/common destination of most calling routes Bus stops will often include timetable information, either the fuil timetable, or for busier routes, the times or frequency that a bus will call at the specific stop. Route maps and tariff information may also be provided, and telephone numbers to relevant travel information services. The stop may also incorporate, or have nearby, real time information displays with the arrival times of the next buses. Increasingly, mobile phone technology is being referenced on more remote stops, allowing the next bus times to be sent to a passenger's handset based on the stop location and the real time information. Automated ticket machines may be provided at busy bus stops.

Bus shelters are often victims of vandalism, whereby certain parts thereof need to be replaced regularly.. Furthermore, the whole shelter or main parts of it, such as the roof, needs to be replaced after a certain time span. Since it is commonplace to use roofing made from fiber glass, the maintenance and replacement of bus shelters has a detrimental environmental effect in addition to being very costly, because fiberglass is virtually non-degradable in nature and is therefore often disposed in landfills ail eternity. This implies that severe environmental problems are associated with the lifecyc!e of traditional bus shelters. Some of these problems can in principle be solved by using bus shelters manufactured from wood - which is biodegradable - as is known in the art. However, manufacturing bus shelters from wood is costly and limits the possibilities of providing a contemporary design. Furthermore, wood shelters require a very high degree of maintenance, and despite thorough maintenance such wood shelters have a significantly Sower lifespan than the average lifespan of 40 years for a bus shelter manufactured from steel/aluminum and fiberglass. There is therefore a need for a bus shelter that is biodegradable and has - in principle - the same or similar properties as those shelters which are made from fiberglass.

SUMMARY OF THE INVENTION

It is thus an object of the present invention to provide a bus shelter manufactured from materials which are at least in part biodegradable and at the same time are as strong and weather resistant as conventional materiais used during the expected life span of a bus shelter. According to the present invention, the above-mentioned and other objects are fulfilled by a bus stop shelter comprising an elongated canopy forming an overhead roof for the bus stop shelter, at least two wall sections, said canopy and wall sections being supported by a framework mounted on a sidewalk, said canopy and wall sections de- fining a partially enclosed covered space providing shade and shelter for people within said enclosed covered space, wherein the canopy comprises a biocomposite material.

Hereby is achieved a bus shelter, wherein the canopy is at least in part bio-degrada- ble, while at the same time having some of the same properties regarding its physical appearance and resistance to weather during the expected lifetime of a conventional bus stop shelter, which is approximately 40 years on average. Furthermore, by using a canopy made from a biocomposite material, the huge detrimental environmental effects of using fiberglass are avoided. Preferably, also the supporting frame of the bus stop shelter comprises a biocomposite material Hereby is achieved a bus stop shelter wherein all those parts which traditionally are made from fiberglass and/or aluminum are avoided. Thus, a much more environmentally friendly solution is achieved, where the bus stop shelter becomes a "cradle to cradle" structure, i.e. a structure which will in a natural way become part of the biological environment from which it is formed.

Preferably, at least one of the wall sections comprises a transparent section, which is connected to said framework Said transparent wall section is preferably made from transparent glass

Preferably, the canopy is placed on top of said framework, said canopy having an upwardly arced shape- According to a preferred embodiment, the biocomposite material is formed by a matrix comprising one or more at least in part biodegradabie plastics and a reinforcement of natural fibers. Preferably, more than 90% of the plastic is biodegradable

According to another embodiment, at least 50% of the matrix is formed by biofogicalfy derived polyester, and the remainder of the matrix is formed by conventional polyester. According to a further embodiment, the biodegradable plastic is derived from renewable natural resources .

According to a further embodiment, the matrix comprises any of the following materials: polyhydraxa!kanoates, poiylactic acid, polybutylene succianate, polycaprolactone, polyanhydrides, and polyvinyl alcohol.

According to a further embodiment, the natural fibers are derived from renewable natural resources. Preferably, the renewable natural resources are any of the following; straw, wood, bark, seed, fruit, leaf, and bast.

According to a further embodiment, the natural fibers comprise any of the following: flax, jute, hemp, sisal, cotton, ramie, kenaf, and wheat. According to a further embodiment, the natural fibers are woven into a plurality of mats.

According to the present invention, the above-mentioned and other objects are fulfilled by a second aspect pertaining to a bus stop shelter comprising an elongated canopy forming an overhead roof for the bus stop shelter, at least two wail sections, said canopy and wali sections being supported by a framework mounted on a sidewalk, said canopy and wall sections defining a partially enclosed covered space providing shade and shelter for people within said enclosed covered space, wherein the canopy and framework comprises a biocomposite material formed by a matrix comprising one or more at least in part biodegradable plastics and a reinforcement of natural fibers.

According to an embodiment of the second aspect, at least 50% of the matrix are formed by biologically derived polyester, and the remainder of the matrix is formed by conventional polyester.

According to a further embodiment of the second aspect, the canopy is formed by a layered structure of alternately matrix and woven mats of natural fibers.

According to a further embodiment of the second aspect, the mats are arranged in such a way that a majority of the individual fibers is aligned in the same direction, thereby providing an increased strength to the canopy along said direction According to a further embodiment of the second aspect, the canopy has an upwardly arced shape, and said direction, along which the fibers are aligned, is a direction that gives an enhanced strength to the arced shape of the canopy.

According to a further embodiment of the second aspect, the framework is formed by a layered structure of alternately matrix and woven mats of natural fibers.

According to a further embodiment of the second aspect, the mats are arranged in such a way that a majority of the individual fibers is aligned in the same direction, thereby providing an increased strength to the framework along said direction.

According to a further embodiment of the second aspect, said direction is substantially vertical when the framework is mounted in its intended use position.

According to a further embodiment of the second aspect, the biodegradable plastic is derived from renewable natural resources.

According to a further embodiment of the second aspect, the matrix comprises any of the following materials: poiyhydroxalkanoates, polylactic acid, poiybutylene succianate, polycaprolactone, polyanhydrides, and polyvinyl alcohol.

According to a further embodiment of the second aspect, the natural fibers are derived from renewable natural resources.

According to a further embodiment of the second aspect, the renewable natural resources are any of the following: straw, wood, bark, seed, fruit, leaf, and bast

According to a further embodiment of the second aspect, the natural fibers comprise any of the following: flax, jute, hemp, sisal, cotton, ramie, kenaf, and wheat,

According to the present invention, the above-mentioned and other objects are fulfilled by a third aspect pertaining to a method of manufacturing a supporting structure for a bus stop shelter, the method comprising the steps of:

- providing a plurality of woven mats of natural fibers,

- providing a matrix comprising biodegradable plastic, and - forming said supporting structure from said plurality of woven mats of natural fibers and matrix.

According to one embodiment of the method according to the third aspect, the step of forming said supporting structure from said plurality of woven mats of natural fibers and matrix is done by hand lay-up

According to a further embodiment of the method according to the third aspect, the step of forming said supporting structure from said plurality of woven mats of natural fibers and matrix is done by vacuum bag moulding.

According to a further embodiment of the method according to the third aspect, the step of forming said supporting structure from said plurality of woven mats of natural fibers and matrix is done by resin transfer moulding.

According to a further embodiment of the method according to the third aspect, the step of forming said supporting structure from said plurality of woven mats of natural fibers and matrix is done by compression moulding. According to a further embodiment of the method according to the third aspect, the step of forming said supporting structure from said plurality of woven mats of natural fibers and matrix is done by pultrusion.

The method according to the third aspect may further comprise the step of impregnat- ing the fibers in the mats with the matrix material using brushes and rollers into a laminated structure of alternating layers of mats and matrix material..

The method according to the third aspect may further comprise the step of curing the consolidated laminated structure at atmospheric pressure

The method according to the third aspect may further comprise the step of curing the consolidated laminated structure at room temperature, or in an oven at a high temperature. The method according to the third aspect may further comprise the step of placing the plurality of mats of woven fibers in a vacuum bag and infuse the matrix material into the fibers by drawing it through the fibers using vacuum, thereby forming a laminated structure of alternating iayers of mats and matrix material.

The method according to the third aspect may further comprise the step of curing the consolidated laminated structure at room temperature or in an oven at a high temperature

The method according to the third aspect may further comprise the steps of hand lay- up of alternating Iayers of matrix material and mats of natural fibers onto a matched die, closing the die, and applying a pressure before the cure takes place.

The method according to the third aspect may further comprise the step of curing the consolidated laminated structure at room temperature, or in an oven at a temperature between 40 to 60 degrees, or between 60 to 80 degrees, or between 80 to 120 de- grees, or between 120 - 180 degrees

According to a further embodiment of the method according to the third aspect, said pressure is between 1 and 5 atmospheres, The method according to the third aspect may in a further embodiment further com- prise the steps of:

- providing a continuous supply of woven mats of natural fibers,

- applying matrix material to the mats, and then

- placing said mats into a pre-heated die in which the matrix material cures, and then - removing the finished mould from the die..

According to a further embodiment of the method according to the third aspect, the continuous supply of woven mats is provided by a roll of a plurality of coherent mats According to a further embodiment of the method according to the third aspect, the step of applying the matrix material to the mats comprises the step of pulling said mats through a bath of matrix material

According to a further embodiment of the method according to the third aspect, the step of applying the matrix material to the mats comprises the step of spraying matrix material on each side of said mats. According to a further embodiment of the method according to the third aspect, the mats are stacked in a iayer comprising a plurality of mats on top of each other before being placed in the pre-heated die

According to a further embodiment of the method according to the third aspect, the mats are stacked in a charge pattern before being placed in the die.

According to a further embodiment of the method according to the third aspect, the temperature of the pre-heated die is between 40 to 60 degrees, or between 60 to 80 degrees, or between 80 to 120 degrees, or between 120 - 180 degrees.

The method according to the third aspect may in a further embodiment further comprise the step of applying a pressure to the plurality of mats in the pre-heated die be- fore the matrix material cures.

According to a further embodiment of the method according to the third aspect, said pressure is between 1 and 10 atmospheres, or between 1 and 7 atmospheres, or between 2 and 5 atmospheres, or between 1 and 3 atmospheres, or between 3 and 6 atmospheres, or between 6 and 8 atmospheres, or between 8 and 10 atmospheres

The method according to the third aspect may in a further embodiment further comprise the step of forming said supporting structure around a biologically derived core material,

According to a further embodiment of the method according to the third aspect, said core material comprises cork and/or bio-potyurethane..

According to a further embodiment of the method according to the third aspect, said supporting structure has a Young's modulus of between 8 and 20 GPa, preferably between 10 and 15 GPa.

According to a further embodiment of the method according to the third aspect, said supporting structure has a flexural modulus of between 8 and 17 GPa, preferably be- tween 8 and 14 GPa According to a further embodiment of the method according to the third aspect, said supporting structure has a flexural strength of between 80 and 120 MPa, preferably between 90 and 1 10 MPa.. According to a further embodiment of the method according to the third aspect, said supporting structure is a canopy and/or a framework of the bus stop shelter.

The matrix in the above mentioned biocomposites holds the fibers together, transfers applied loads to those fibers and protects them from mechanical damage and other environmental factors.

BREIF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of the present invention may be realized by reference to the remaining portions of the specification and the drawings. In the following, preferred embodiments of the invention are explained in more detail with reference to the drawings, wherein

Fig, 1 shows an embodiment of a bus stop shelter,

Fig. 2 shows another embodiment of a bus stop shelter,

Fig. 3a - 3f shows various embodiments of bus stop shelters, and

Fig. 4 shows an embodiment of a method according to the invention.

DETAILED DESCRIPTION

The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. The invention may however be embodied in different forms and should not be construed as limited to the embodiments set forth herein Rather, these embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the invention to those skilled in the art. Like reference numerals refer to like elements throughout. Like elements will, thus, not be described in detail with respect to the description of each figure Fig. 1 shows an embodiment of a bus stop shelter 2 according to the invention. The illustrated bus stop shelter 2 comprises an elongated canopy 4 forming an overhead roof for the bus stop shelter 2. The bus stop shelter 2 also has three wall sections 6, 8, 10, two end or gable wail sections 6 and 8, and a side section 10, In the illustrated embodiment, the side section 10 comprises three glass wal! elements in order to enhance the vision of a user of the bus stop shelter 2. The canopy 4 and wall sections 6, 8, 10 are supported by a framework mounted on a sidewalk 12. In the illustrated embodiment, the framework forms an integral part of the gable wall sections 6 and 8. The canopy 4 and the wall sections 6, 8, 10 define a partially enclosed covered space providing shade and shelter for people 14 within said partially enclosed covered space. The canopy 4 of the illustrated bus stop shelter 2 comprises a biocomposite material, which can be a biocomposite material as described above.

Hereby is achieved a bus shelter 2, wherein the canopy 4 is at least in part bio-de- gradable while at the same time has some of the same properties regarding its physical appearance and resistance to weather during the expected lifetime of a conven- tional bus stop shelter, which is approximately 40 years on average. Furthermore, by using a canopy 4 made from a biocomposite material the huge detrimental environmental effects of using fiberglass are avoided. Preferably, also the supporting frame, which in the illustrated embodiment is embodied as two gable sections 6 and 8, of the bus stop shelter 2 comprises a biocomposite material. Hereby is achieved a bus stop shelter 2 wherein all the parts that are traditionally made from fiberglass and/or aluminum are avoided. Thus, a much more environmentally friendly solution is achieved, where the bus stop shelter 2 becomes a "cradle to cradle" structure, i.e.. a structure which in a natural way will become part of the biological environment, from which it is formed. In a preferred embodiment of the illustrated bus stop shelter 2, any of the two gable wall sections 6 and 8 may be configured for displaying advertisements,

Fig. 2 shows an alternative embodiment of a bus stop shelter 2 according to the invention. In this embodiment one of the gable wall sections 6 is embodied as a transparent glass wail. The canopy 4 and wall sections 6, 8, 10 are supported by a framework 16 mounted on a sidewalk 12. In the illustrated embodiment the framework 16 comprises four poles, onto which the sidewalls 6, 8, and 10 are mounted. The canopy 4 is also mounted on top of the four poles. The canopy 4 of the illustrated bus stop shelter 2 comprises a biocomposite material, which can be a biocomposite materia! as described above, and the framework 16 is in a preferred embodiment also formed by a biocomposite material. However, in an alternative embodiment the framework 16 may be formed by a metal, such as aluminum. In the illustrated embodiment the wall sec- tion 8 may furthermore be formed at least in part by a biocomposite material. As illustrated, the wall section 8 is equipped with an advertisement.

Fig. 3a-3f show various alternative embodiments of a bus stop shelter 2 according to the invention, In fig. 3a-3e one of the wall sections 8 or 10 comprises an advertisement. In Fig. 3f the wall sections 6 and 8 constitute a framework supporting the canopy 4. !n ail the figures 3a-3f, the canopy 4 is formed from a biocomposite material, which may be a biocomposite as described above. Preferably, the wall sections 8 in figures 3a-3d also comprise a major part of biocomposite material Additionally, the wall sec- tion 6 in figures 3a-3c, and 3e comprises a major part of biocomposite material. In the final figure 3f, both gable wall sections 6 and 8 are preferably made of a biocomposite material. As illustrated, the wail section 10 comprises at least in part a transparent glass wall. Fig, 4 schematically illustrates an embodiment of a method of manufacturing a supporting structure for a bus stop shelter from biocomposite materials. Said supporting structure may be a canopy and/or framework.

The illustrated method comprises the step 18 of providing a continuous supply of wo- ven mats 22 of natural fibers. These mats 22 are supplied by a roll 20 of a plurality of coherent mats 22 The mats 22 are cut from the roll 20 by a cutting tool 24. Then in step 26, a matrix material is applied to the mats 22

The step of applying the matrix material to the mats 22 may comprise the step of pull- ing said mats 22 through a bath of matrix material, or as illustrated, matrix materia! is sprayed on each side of said mats

Then in step 28 the mats 22 are stacked in a layer comprising a plurality of mats 22 on top of each other. The mats 22 are preferably stacked in a charge pattern before being placed in a pre-heated die 36 in the subsequent step 30, illustrating the placing of said mats 22 into the pre-heated die 36, in which the matrix material cures.

The temperature of the pre-heated die 36 is preferably between 40 to 60 degrees, or between 60 to 80 degrees, or between 80 to 120 degrees, or between 120 to 180 de- grees. In the subsequent step 32, pressure is applied to the plurality of mats 22 in the preheated die 36 This pressure is applied before the matrix material is allowed to cure.

The applied pressure may be between 1 and 10 atmospheres, or between 1 and 7 atmospheres, or between 2 and 5 atmospheres, or between 1 and 3 atmospheres, or between 3 and 6 atmospheres, or between 6 and 8 atmospheres, or between 8 and 10 atmospheres.

Finally in step 34, the finished mould (e g a canopy 4 or a part of a framework for a bus stop shelter) is removed from the die 36,

The illustrated method may further comprise the step of forming said supporting structure around a biologically derived core material, which may be placed between a number of mats 22 of natural fibers Examples of such biologically derived core mate- rials may be cork and/or bio-polyurethane.

LIST OF REFERENCE NUMBERS

In the following is given a list of reference numbers, which are used in the detaiied description of the invention 2 bus stop shelter,

4 canopy,

6, 8, 10 wall sections,

12 sidewalk,

14 person,

16 framework,

18 step of providing woven mats of natural fibers,

20 a roll comprising a plurality of coherent mats of natural fiber,

22 woven mats of natural fiber,

24 cutting tool,

26 step of spraying the mats with matrix material,

28 step of stacking a plurality of mats in a layer,

30 step of placing said layer of mats into a pre-heated die,

32 step of applying pressure to said laminated structure of mats and matrix material,

34 step of removing the finished mould from the die, and

36 die.