ES2302422A1 - Solar kitchen for concentration, has hub that is made of parabolic folding tissue, and plasticized for feasible washing and finishing, and double zipper closure is prepared to allow vertical pipe to run through tripod-support - Google Patents

Abstract

The solar kitchen has a hub that is made of parabolic folding tissue, and plasticized for feasible washing and finishing. A double zipper closure is prepared to allow the vertical pipe to run through tripod-support inside the parabolic concentrator.

Description

Concentrating Solar Cooker, deep focus, High performance, foldable, lightweight, about Tripod-stand, for cooking food.

Technical sector

The invention falls within the field of renewable energy, solar energy and more specifically its use in solar kitchens for cooking foods.

State of the art

According to legend, during the siege of the city of Syracuse in the year 212 a. C., Archimedes managed to burn several Roman ships concentrating on them the sunlight by Mirrors. I already knew perfectly the enormous potential of lightning solar. Leonardo da Vinci also designed a parabolic mirror concentrator

Advances in energy use solar in food preparation came from Horace's hand de Saussure who in 1767 built a small solar cooker that It consisted of two boxes of pine wood, one inside the other incorporating a glass cover. These types of kitchens have been It has been improving until today, they are called Cookers-oven. In them it is possible to reach temperatures up to 160 ° C. Their volume and weight do not make them especially movable The cooking process is slow and not allow access to food during it, because it would lose much of the heat accumulated inside thanks to greenhouse effect.

The other big group of Kitchens are the called Concentrated Solar Kitchens using, either reflective planes at different angles that converge in a determined surface or on parabolic surfaces that They concentrate solar radiation on a line or point.

In this regard, in patent FR 2565678 of Marc Preaubert, from June 1984, proposes a Solar Cooker composed of a rigid chassis of three concentric circles in different planes, 20 stackable sheets as a fan and a bearing structure system composed of three feet of approximately one meter high and two joining pieces equally approximately one meter in length and placed horizontally. Hanging on the horizontal tubes, four chains support a transparent base on which Place the container to heat the food.

In US Patent 3643648 of Adnan S. Tarcici, of February 1972, a Solar Kitchen composed of a box is proposed which serves as an element for transportation. Once opened, we deploy the base-support of the whole set, likewise we unfold the support of the cooking vessel. The sheets that make up the semi-parabolic surface unfold as a fan.

In patent ES 2128264, by José Manuel Arenas Reina, May 1999, proposes a Solar Kitchen composed of a support structure in which a parabolic concentrator

The sixteen parabolic concentrator sectors, it is made of cardboard on one of whose surfaces are It has adhered a metallic sheet that confers power of reflection. In the main axis of the support, in the inner zone of the concentrator an adjustable base is placed on which the cooking container

Analyzing the three cases exposed previously we can verify that:

In the patent FR 2565678 of Marc Preaubert, It refers to its portability. We must have in note that at best we have a structure of a meter by meter, a long series of independent tubes that configure the supporting structure, an arm-support of the parabolic concentrator that must have the stiffness (weight) necessary to avoid deformations, which requires a wide assembly time

Its operation is complicated and uncertain. Complicated since the necessary reorientation of the concentrator, in vertical direction (latitude), forces to release the kneecap (17), having to manually bear the weight of it during the adjustment process

In the longitudinal direction we must move all the cook and given that the legs are far from each other approximately one meter, the process seems complex. Yes We value that reorientation in kitchens with concentrators parabolic must be done every 20 minutes, we see that we have a constant and laborious task.

Apart from the above details, the Operation is uncertain. We do not have an element that we ensure the perfect orientation of the concentrator plane parabolic in perpendicular position with respect to the rays solar, of what we conclude in the relative efficiency of it, along with a volume that make it not very advisable for the transport.

The focus is far outside the plane of the parable, from which glare problems arise and performance due to a greater deviation from the concentration of reflections motivated by deformations in the parable, we must keep in mind that the sheets are superimposed on each other in the axis of rotation and that makes the reflection geometries be different. On the other hand, the cooking vessel is located very little protected from the air with the consequent loss of temperature.

In US Patent 3643648 of Adnan S. Tarcici, of one side we have that the weight of the kitchen is not distributed evenly and we either make the base-support of the set or we can take the risk of involuntary overturn in case of light wind.

The cooking vessel is on the support (30) at a considerable height from the ground with the instability conferred by that position, as well as with the increase in temperature loss due to wind.

The orientation of the whole set is done moving the semi-parabolic system, having to endure manually the weight of it during the adjustment process, adjust which on the other hand is done approximately by not having a precise element. In parallel to the reorientation of the whole concentrator, we must move the support of the container cooked (30), to match the focus. We will have to remove it before proceeding to the mentioned adjustment.

Regardless of the temperature loss, this maneuver forces the aforementioned stability from the axis of maximum stability container, contributing to increase the instability of all the kitchen. As in the previous patent, if we consider that the reorientation in kitchens with parabolic concentrators must of be done every 20 minutes, we see that we have a constant task and laborious

As in the previous patent, the focus is It is very far from the plane of the parable, from which they derive glare and performance problems due to increased deviation from the concentration of the reflections motivated by deformations in the parabola, we must bear in mind that the sheets overlap one on the other in the axis of rotation and that does that the geometries of reflection are different. On the other hand, the cooking vessel is very little protected from the air with the consequent loss of temperature.

In patent ES 2128264, by José Manuel Arenas Queen, on the one hand, as can be seen from the attached drawings in the mentioned patent, the support of the container is not found on the hub axis of the concentrator with the consequent losses of efficiency Based on the necessary reorientation to be be done every 20 minutes, we see that for correctness longitudinal, we have a kneecap (23). We must therefore release the concentrator and the container holder for cooking, with the container and food inside, turning it until the right position to immobilize it again. This operation, apart from dangerous because we can run the risk of burning for the spilling of food that is high temperature, it is uncertain to not have an element that we let you know the orientation to the point of maximum efficiency.

To achieve full correction in the direction longitudinal, regardless of the maneuver discussed above, we must turn the base-stand since the arc described by the swivel (23), does not match the sweep of the Sun, not even in all seasons of the year is the same.

To correct the orientation vertically (latitude), we must either reduce the leg length center (3) so that the concentrator is placed more vertically, increase the length of the other two legs, or shorten the distance from the central leg to the second.

In any case we must remove from your Support the cooking container. Once the maneuver is done, always approximate, we must also proceed to readjust the container support (19) until placed parallel to the floor to cook again. These maneuvers, given that they must be done every twenty minutes, complicate the process a lot, with temperature losses and possible accidents.

As the sun makes one more trajectory high, coinciding with the summer months, the support base will go having less surface when having to place almost parallel to I ground the plane of the concentrator, which implies that have to be placed, almost perpendicular to the ground, the leg principal.

The concentrator of this patent, not being a continuous surface that would be the ideal configuration, it has sixteen sectors, which inevitably have a loss of significant performance when generating sixteen reflection planes and greatly expand the diameter of the concentration focus. A minor number of sectors, lower efficiency.

Likewise, it is impossible to avoid Food splashes during the cooking process. The elements of the concentrator, being manufactured with cardboard they allow their washing with the consequent loss of effectiveness.

Its focus is outside the plane of the parable, from which glare problems arise and performance due to a greater deviation from the concentration of the reflections The cooking vessel is outside the heat concentrator plane, very little protected from air, with the consequent loss of temperature.

Explanation

Therefore, the present invention has as object to solve the problems listed above, contributing a series of solutions that contribute to achieving a "Kitchen Solar Concentration ", deep focus, fully foldable, very light, easy to transport given its small weight and volume, washable, with a system that allows its orientation to get high efficiency, totally stable, with fast handling and Simple and with a high degree of security.

Grossly, although next we will go detailing each element of the Solar Kitchen and its specific function, the invention consists of three sets, namely a TRIPOD-SUPPORT of the entire system, (Figure 2), a Folding PARABOLIC CONCENTRATOR, (Figure 3), whose axis is arranged the support of the cooking vessel, (Figure 6), and the SOLAR EFFICIENCY DETECTOR, (Figure 4). All the materials used in manufacturing are commercial, although once Start-up manufacturing in large series, there will be parts that they will be replaced by others made of plastic by injection processes, which, without diminishing performance, will affect  positively in reducing weights and costs. These three sets are introduced in a small bag for transport, (Figure 9).

As we can see (Figure 2), the TRIPOD-SUPPORT, is composed of a tube, (Figure 2) (1), preferably made of aluminum because it is a material that, once anodized, has a weight / resistance ratio  very high, it can also be manufactured in plastic materials with high mechanical resistance and stable against temperatures important. At the base of this tube, we have a bushing, (Figure 2) (2), in solidarity with it, in which the three folding legs, (Figure 2) (3).

A second cap, (Figure 2) (4), which is slide down the vertical tube, it has three articulated arms, (Figure 2) (5), which attached at the other end to the center of each respective folding leg, (Figure 2) (3), confer stiffness necessary once the total opening is made. The blocking of the opening position, is achieved with a retractable fixative, (Figure 2) (6), placed inside the vertical tube.

The PARABOLIC CONCENTRATOR, is manufactured with tissue, (Figure 3) (7), plasticized, feasible to be washed, Bright and high reflective power. Twenty four or more triangles of this material, in which the sharpest angle has a ideal opening, they join, one to another, by means of a seam longitudinal, not straight, that with the relevant curvature, we will allow to have a modified, deep-focus parable, that meets our needs as will be seen later, avoiding the problems of glare, accidental burns and greater efficiency when said focus is closer to the surface reflective and therefore subject to minor deviations caused by small deformations of said concentrator parabolic. On the other hand the location of the cooking vessel below the surface of the parabola offers protection against to the sweep of winds that would lower the temperature and, for consequently, the performance of the solar cooker.

In one of those triangles, coinciding with the bisector of the sharpest angle, prior to cutting, there is sewn a double zipper, (Figure 5) and (Figure 7) (23), and in the that both closures are joined by a piece, (Figure 5) (20), which It has a central drill. Later we will see the function of This mechanism

Logically, the larger the diameter outside the parabolic concentrator, the greater the efficiency energy of solar cooking. To define the dimensions, We will seek a balance between efficiency and ease of transport once folded.

A number of rods equal to that of triangles, thin and flexible, (Figure 3) (9), are arranged along of each of the reference seams previously.

One of its ends is fixed on the edge of the parabolic concentrator, introducing each of them in others so many unit caps, (Figure 3) (21), sewn to the edge of the cloth. The other end is connected by a wire, which meets hinge function for all rods, to a bushing central, (Figure 3) (10), which has the same number of slots to that of rods, arranged radially and a mechanized throat in its periphery, in which the mentioned wire is inserted. The parabolic concentrator fabric will have its bright face on Contact with the mentioned rods.

So many other rods, (Figure 3) (11), with a Length shorter than the previous ones and joined to these approximately in the middle of them, using a drill and a small pin, they will be joined by the other end by a wire, to another central bushing, (Figure 3) (12), which has the same number of radially arranged grooves and a mechanized throat in its periphery, in which the mentioned wire is inserted. Of the center of this bushing, a tube, (Figure 3) (13), attached in solidarity with it, it extends towards the center of the parabolic concentrator, sliding inside the bushing, (Figure 3) (10), and protruding from the rear of the concentrator

In the other direction of the bushing, so oscillating, the positioning support of the container is anchored cooked, (Figure 3) (14) and (Figure 6), which, in turn, has four metal rods, (Figure 6) (15), pertinently bent that, by an elastic system and thanks to some grooves practiced to the support of placement of the container, allows to leave them fixed and safe in working position or folded for transport. Of the center of this cooking vessel holder, in the direction opposite to the zone of placement of the container, an axis, (Figure 6) (16), is responsible for joining the concentrator system parabolic with the tripod-stand, entering inside the vertical tube thereof, (Figure 2) (1), and allowing the parabolic concentrator assembly to rotate freely.

As the bushing (Figure 3) (12), and (Figure 6) (12), is attached to the tube (Figure 3) (13) and (Figure 6) (13), which passes through the inside of the bushing (Figure 3) (10), the system of opening is similar to that of an umbrella but vice versa, that is, we will take the end of the tube that protrudes from the top of the parabolic concentrator and we will wear the cap (Figure 3) (10) forward, approaching the bushing (Figure 6) (12), until a retractable fixative, (Figure 3) (22), equal to used to lock the opening position of the support tripod, (Figure 2) (6), placed in the Inside the tube leave the opening position fixed.

Being a deep focus hub, this focal point is below the hub plane parabolic.

In the case of having to do the extension with the conventional umbrella deployment system, that is by the interior, once opened, we would have an axis ahead too long that would force us to make a retractable system, to achieve the focal length, increasing the number of mechanisms, weight and less stiffness.

In the tube that starts from the cap, (Figure 3) (12), and goes through the bushing (Figure 3) (10), we will attach the SOLAR EFFICIENCY DETECTOR, (Figure 3) (17) and (Figure 4). This small decoupling mechanism, is composed of a plate of aluminum, (Figure 4) (17), or other lightweight and resistant material.

At one of its ends there is a coupling attached elastic, (Figure 4) (18), shaped like "Omega", which we allows you to do it quickly and reliably and safely with the tube mentioned above, (Figure 3) (13) and (Figure 4) (13).

On the other end, and placed perpendicular to the plane of the plate, a rod, (Figure 4) (19), joined by welding or other reliable system, but always through the rear area to avoid a connection with the front area irregular areas, is responsible for informing us about the location  of the parabolic concentrator and the need to redirect it properly in order to achieve optimum performance.

The final assembly of the solar cooker is Performs as follows: Once we have the tripod-stand deployed, with fixer retractable perfectly locked and with the central tube towards above, we deploy the parabolic concentrator until the Corresponding esacamoteable fixative block this position, we introduce the mentioned tube, (Figure 29) (1), through the hole the piece that joins the two fastener zip fasteners parabolic, (Figure 5) (20), proceeding to introduce inside  thereof, the axis of the support of the cooking vessel, (Figure 6) (16). We only have to deploy the four rods metallic, (Figure 6) (15), which define the area to place the cooking bowl

The kitchen is ready to work. We place the food to be cooked inside the container and We don't touch that container again. We will proceed to guide the kitchen.

We must adjust in two directions, in length and in latitude. To do this, we must first observe the solar efficiency detector, the maximum performance position of logically, we will obtain it when the plan of the parabolic concentrator is completely perpendicular to the path of the sun's rays.

As the axis of the solar efficiency detector, Once coupled to the parabolic concentrator tube, it is perpendicular to the plane of the mentioned concentrator, we just it remains to move said concentrator in both latitude and longitude until you get that at the junction of the detector plate of efficiency, area that is painted white, with the axis of said detector, no shadow is generated.

The orientation in length, (Figure 7), it is simply achieved by rotating the entire assembly of the parabolic concentrator in the horizontal plane. Once in the solar efficiency detector we don't have the diagonal shadow, but up or down, we confirm that longitudinally We are perfectly oriented, we just have to go up or down the angle of the parabolic concentrator to orient it latitudinally.

Taking the end of the central tube of the parabolic concentrator protruding from the rear, we will proceed to change this angle, (Figure 8). The disposition of the connecting piece between the two zipper closures, (Figure 5) (20), allows us to raise or lower this angle until the total absence of shadow. The double zip system we confers a resistant parable, without deformations, but allowing an element to cross its surface without losing rigidity.

Once the cooking process is finished, we will proceed to perform disassembly and folding of the elements, namely parabolic concentrator, tripod-stand, and solar efficiency detector. The set is introduced in a small bag that facilitates transport and storage, (Figure 9).

Claims (10)

1. Concentration Solar Cooker, characterized by having a PARABOLIC CONCENTRATOR (Figure 3) (7), deep focus, high performance, foldable. A FOLDABLE TRIPOD, (Figure 2). A SOLAR EFFICIENCY DETECTOR, (Figure 4), a support for the cooking vessel, (Figure 6). A BAG made of lightweight and flexible material for transport (Figure 9). 2. Concentration Solar Cooker, according to claim 1, characterized by having a parabolic concentrator made of thin, light fabric, feasible to fold, to be washed, with a glossy finish, high reflective power and stable in durability in relation to the incidence of the sun's rays 3. Concentration Solar Cooker, according to claims 1 and 2, characterized in that the parabolic concentrator is composed of twenty-four triangles or more, in which the most acute angle has an ideal opening, joined to each other by the longer sides by means of a longitudinal seam, not straight, which, with the relevant curvature, will allow us to have a modified parabola, whose deep focus is within the plane of the parabola. 4. Concentration Solar Cooker, according to claim 3, characterized in that, in one of the triangles of the parabolic concentrator, coinciding with the bisector of the most acute angle, a cut is made with the length of said bisector, but leaving a small area without cutting at both ends. A double zip fastener is subsequently sewn onto this cut, (Figure 5) and (Figure 7) (23), and in which both closures are joined by a piece, (Figure 5) (20), made of aluminum or another lightweight material, even plastic, which has a central hole, with a diameter equal to the vertical tube of the tripod-support (Figure 2) (1). 5. Concentration Solar Cooker, according to claim 1, characterized in that the configuration of the parabolic concentrator, in the unfolding process, is obtained by using so many flexible rods, (Figure 3) (9), as triangles containing said concentrator, attached on one side to the bushing (Figure 3) (10), made of aluminum or other lightweight material, including plastic, which has grooves, in equal number to rods, arranged radially and a mechanized throat at its periphery, in which it remains introduced the fixing wire of all the rods and that fulfills the function of hinge for them, and on the other hand to the unit blind caps, (Figure 3) (21), sewn in the perimeter of the tissue of the parabolic concentrator. A series of shorter rods, (Figure 3) (11), in equal numbers to the rods (Figure 3) (9), arranged perpendicular to them, joined at one end to them, about half its length, using a small pin, and on the other to the bushing (Figure 3) (12), manufactured in aluminum or other lightweight material, even plastic, which has grooves, in equal number to rods, arranged radially and a mechanized throat in its periphery, in which it remains introduced the fixing wire and that fulfills the function of hinge for all rods. 6. Concentration Solar Cooker, according to claim 1, characterized in that it has a solar efficiency detector, (Figure 4), comprising a plate, made of aluminum or other lightweight material, including plastic (Figure 4) (17), in one of whose ends we have an axis, (Figure 4) (19), perpendicular to the plane of the mentioned plate, joined by welding, rivet, adhesive or any other system, and in the other, an elastic anchorage system shaped of "Omega", (Figure 4) (18), with the opening of the aforementioned "Omega" in prolongation of the plate, as seen in (Figure 4), manufactured with metal strap or plastic material that allows its deformation in the process of placing on the tube, (Figure 4) (13), and its subsequent recovery of the initial form, (Figure 4) (18). 7. Concentration Solar Cooker, according to claim 1, characterized in that the tripod-support consists of a series of parts that can be made of aluminum or other lightweight material, including plastic, namely a central vertical tube (Figure 2) (1 ), which supports the weight of the cooking container, two bushings, one fixed to the mentioned tube, (Figure 2) (2) and the other movable, (Figure 2) (4), and a folding leg system, (Figure 2) (3), stiffened by the respective arms, (Figure 2) (5), which allow its extension with a fixing system in the opening position, consisting of a retractable bolt, (Figure 2) (6). 8. Concentration Solar Cooker, according to claim 1, characterized in that at the end of the tube, (Figure 3) (13), which runs through the center of the parabolic concentrator, through the socket, (Figure 3) (10), joined to the bushing that is integral with said tube, (Figure 3) (12), there is a support for the cooking vessel, (Figure 6) (14), made of aluminum or other lightweight material, even high temperature resistant plastic, coupled to the aforementioned bushing, (Figure 6) (12), by means of an oscillating system. It has four metal rods, (Figure 6) (15), pertinently folded that, by means of an elastic system and thanks to some grooves made to the support of placement of the container, allows them to be fixed and safe in working position or folded for transport. 9. Concentration Solar Cooker, according to claim 7, characterized in that the weight of the cooking vessel always remains perpendicular to the support tripod tube, (Figure 2) (1). 10. Concentration Solar Cooker, according to claim 1, characterized in that once the three elements that make up this kitchen are folded, namely, folding concentrator, folding tripod-stand and solar efficiency detector, they are introduced in a small bag for transport, (Figure 9).