JPH01179864A - Portable solar cooker utilizing fresnel mirror - Google Patents

Abstract

PURPOSE:To reduce the overall weight of the device and improve the collecting efficiency of solar light by using a Fresnel mirror to reflect and collect the solar light. CONSTITUTION:The Fresnel mirror 1 to reflect and collect the solar light is made of a polypropyrene sheet and focuses the light to a point, and the rear of it is coated with aluminum by vacuum evaporation. The orientation is such that when the mirror side 1 is set perpendicular to the solar light, the reflected light of the solar light hitting the mirror is focused to the underside of a cooker mount 2 which is supported by two legs 8. The mount 2 has a circular depression 3 in its flat top, which acts as a pot the rear of which is treated with frosted black for effective light absorption. The arm 4 is a support for the Fresnel mirror 1, and is designed to track the sun so that the solar light may always be perpendicular to the mirror. By this constitution, the weight can be reduced and the light collecting efficiency can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Object of the Invention) Conventionally, devices that rely on solar heat as a heat source for cooking, so-called solar cookers, have often been used, particularly in developing countries. However, they are generally crude and do not necessarily perform a sufficient function. As a result, reckless firewood collection continues, spurring desertification. On the other hand, even in developed countries, direct and indirect environmental destruction and deterioration is increasing due to heavy consumption of fossil fuels.

In recent years, there has been a movement toward alleviating these problems, and some attempts have been made to proactively utilize natural energy. In these difficult times, we would like to offer a solar shoe with new features not found in conventional shoes, which will help solve the problem and increase opportunities for contact with nature. be.

(Structure/Characteristics of the Invention) The features of the solar shoe provided by the present invention are a) good performance not found in conventional products, and b) compactness and light weight for convenient portability. To achieve this feature, a Fresnel mirror is used to reflect and focus sunlight. Conventionally, a rotating parabolic mirror was used for this part, but when trying to make it more compact for portability, the mirror surface itself was curved, which made it very difficult to fold and store it. Ta. In this respect, since the Fresnel mirror is in the form of a thin flat plate, this matter is extremely easy. In addition, since the deflection of the mirror is reduced, the weight of the mirror itself can be minimized. This greatly contributes to reducing the overall weight of the solar vehicle.

Figure 1 shows the appearance of the prototype solar shoe during operation. The outline of the device will first be explained with reference to this figure.The Fresnel mirror 1 is a point-concentrating Fresnel lens with a focal length of 50 cm, made of a polypropylene sheet approximately 1 mm thick, and vacuum-deposited aluminum on the back surface to reflect sunlight. It has been subjected. The size of this mirror is 1.0
m Xl, 3 m When this surface is oriented perpendicular to the sunlight, the reflected light of the sunlight hitting the same surface is the lower surface of the kicker stand 2, which is supported by two legs 8 and has a height of 95 cm from the ground. The light is focused nearby. This platform 2 has a circular bevel 3 with a diameter of 30 cm and a depth of about 150 m.
This depression functions as a so-called pan. The back side of this bezel 3 is matte black for more effective light absorption. Arm 4 is a support for the Fresnel mirror, and by using point 5 as a fulcrum and moving point 6 on the arm appropriately along slit guide 7, it tracks the sun so that the Fresnel mirror surface always faces perpendicular to the sunlight. . The effect of this device is approximately 85% of solar radiation.
According to actual measurements at 0W/m and a temperature of 26°C, approximately 1
8°012 liters of water reaches its boiling point in 7 minutes.

Figure 2 shows how the device is folded; first, the two legs 8 are each pushed with part a into part 1) and part C into part C! , 90' is bent and placed in the section d. After that, this part is the storage container 9
It is pushed into part e of. The Fresnel mirror 1 is folded into four pieces and placed in the storage container 9 together with the arm 4, and the lid is moved in the direction of the arrow to close the Fresnel mirror 1. As a result, when fully folded and stored, it measures 60cm long and 80cm wide.

It has a thickness of 15 cm, and can be carried by lowering it by using the handle 10. The entire model ■ weighs approximately 8 kg.

(Effects of the Invention) In the present invention, by using a sheet-like Fresnel mirror, the weight of the entire device is reduced, and the size when folded and stored is also reduced. As a result, it has become easier to carry and the opportunities for its use are increasing. Moreover, since the thickness of the Fresnel mirror is very thin, approximately 1 mm, there is a small loss due to absorption of light, and the activity of concentrating and utilizing sunlight is extremely high. In addition, by incorporating many folding mechanisms into the entire device, the device is also very thin to carry.

[Brief explanation of the drawing]

FIG. 1 is an external view of the solar puller when it is in operation. FIG. 2 is a diagram for explaining the process of folding and storing the device. January 11, 1985 Inventor: Ishi Fujii
Silver flute 2 illustration

Claims (1)

[Claims] 1) A solar cooker characterized by using a Fresnel mirror to reflect and concentrate sunlight. 2) The solar cooker according to claim 1, wherein the device support part is also lightweight and has a structure that can be folded compactly, making it easy to carry.