RU2745978C1 - Housing-radiator of the led lamp - Google Patents

Abstract

FIELD: lighting engineering.

SUBSTANCE: invention relates to lighting engineering, namely, to the design of the housing-radiator of a LED lamp and can be used in greenhouse crop production, as well as for lighting various rooms. The claimed heat-conducting housing-radiator of the LED lamp is made of separate longitudinal profiles 1 of solid section. In the middle of the inner side of the cross-section of the profile, a longitudinal rib 2 is made directed to the center of the cross-section of the radiator housing. On the outside of each profile, at least one led light source 3 is fixed. The profiles are connected to each other by connectors 4, so that planes of the outer surface of the profiles in the cross section of the housing form an equilateral polygon. Between the longitudinal edges 5 of the nearby profiles there are air gaps 6, the width of which, the "B" at the lower end and the “V” at the upper end is made with respect to the inequality B ≤ V.

EFFECT: technical result is increased efficiency of heat transfer from the inner surface of the radiator housing to the environment, which will reduce the weight and overall dimensions of the radiator housing, while maintaining the power of the lamp.

1 cl, 4 dwg

Description

The invention relates to lighting engineering, namely, to the design of a radiator housing as a component of an LED lamp and can be used in greenhouse plant growing, as well as for lighting various premises.

State of the art

The main factors constraining the widespread use of known LED lighting devices for lateral irradiation of plants in greenhouses are:

- a large mass of the device, and therefore the whole lighting installation, leading to an increase in the load on the supporting structures of the greenhouse;

- Insufficient luminous flux of known LED lamps for lateral illumination of a tall agricultural crop inside a bush of plants.

These factors are a consequence, among other things, of insufficient efficiency of heat transfer of light-emitting modules through the body-radiator to the environment.

Known analogue "LED lamp with dynamic convection cooling" according to RU 124 361 U1, 06.09.2012 [1]. The luminaire contains at least one hollow body-radiator made of a heat-conducting material, on the outer surface of which an LED light source connected to a power source is fixed, characterized in that the body-radiator of the lamp is made in the form of a piece of a hollow pipe with open ends and a profile with section in the form of a polygon: rectangle, square, triangle. The axis of the housing-radiator is slightly inclined or vertical position of the luminaire.

The advantage of this solution is that heat transfer from the heat-conducting body occurs along the shortest path directly into the environment, both from the outer and from the inner surfaces of the body-radiator.

The disadvantages of the known analog are as follows:

- when using the luminaire for the purpose of lateral illumination of tall agricultural plants inside the bush, the required length of the lamp housing-radiator should be 2-2.5 m.With such a length of the housing made of a hollow pipe, its hydraulic resistance to the movement of the air flow, cooling the inner surface of the profile, will increase proportionally its length and will be a factor limiting the amount of cooling air passing per unit of time inside the luminaire body. This leads to a decrease in the efficiency of heat transfer from the inner surface of the case;

- in the area of the inner angles of the cross-section of the profile in the form of a polygon, the flow of the cooling air flow has a lower speed and has a laminar character, which further reduces the efficiency of heat transfer from this part of the inner surface of the profile. This disadvantage is most pronounced for a hollow tube with a triangular cross section.

To ensure the required amount of heat transfer, an increase in the cooling surface of the case is required, while the overall dimensions, weight and cost of the device will increase.

The closest solution in terms of the achieved technical result, adopted for the prototype, is the well-known "LED lamp ..." according to RU 2699013 U1, 09/03/2019 [2]. The luminaire contains a heat-conducting body-radiator, consisting of several separate longitudinal profiles of a solid cross-section, with an LED module placed on each of them. The planes of the outer surfaces of the profiles form an equilateral polygon in the cross-section of the body. The profiles are fastened together with connectors to form air gaps between the longitudinal edges of the adjacent profiles, the width of which, "B" at the lower end and "C" at the upper end, is made in compliance with the inequality B ≤ B.

The disadvantage of the known prototype is the large unevenness, in the cross-section of the radiator housing, of the parameters of the longitudinal air flow, namely: speed, temperature and degree of its turbulence.

The parameters of the movement of the longitudinal air flow in the cross-section of the body-radiator of the prototype can be described as follows: From the inner surface of the body-radiator, part of the thermal energy emitted by the LED module is transferred to the environment. As is known, in the case-radiator in the form of an equilateral polygon, the velocity of the longitudinal air flow, near the inner surface of the profile, reaches a maximum value and, with distance from the profile, towards the center of the cross-section of the case-radiator, the speed decreases to a minimum. In the same direction, simultaneously with the speed, the temperature of the air stream also decreases. This leads to a decrease in the degree of turbulence of the longitudinal air flow in the central region of the radiator housing. In this case, a large proportion of heat is transferred by a part of the longitudinal air flow moving in the immediate vicinity of the longitudinal profiles 1 and, a much smaller proportion of heat is transferred by a part of the longitudinal air flow moving in the central region of the cross-section of the radiator housing.

Thus, it can be stated that, due to these reasons, the contribution of the longitudinal air flow of the central region of the radiator housing to the process of heat transfer to the environment is much less than the contribution of the air flow of its peripheral region and this leads to insufficient efficiency of heat transfer from the inner surface of the housing as a whole. radiator.

These disadvantages in the known prototype are compensated by an increase in the width of the longitudinal profile in order to increase the cooling surface of the radiator housing. The result of this decision is an increase in the mass of the radiator housing and its overall dimensions.

Disclosure of the essence of the invention.

The invention is aimed at eliminating the above disadvantages of the prototype associated with insufficient efficiency of heat transfer from the inner surface of the radiator housing.

The technical problem solved by the invention is to reduce the weight and overall dimensions of the LED lamp housing-radiator.

The technical result of the claimed invention is: increasing the efficiency of heat transfer from the inner surface of the radiator housing to the environment.

In the known heat-conducting body-radiator, consisting of several separate longitudinal profiles, solid cross-section, on each of which an LED module is placed, the planes of the outer surfaces of the profiles form an equilateral polygon in the cross-section of the body, and the profiles are fastened together with connectors to form, between the longitudinal edges adjacent profiles, air gaps, the width of which, "B" at the lower end and "B" at the upper end, is made in compliance with the inequality B ≤ B, the technical result is achieved due to the fact that the claimed invention has the following differences:

- a longitudinal rib is made on the inner side of the cross-section of the profile,

- the rib is directed from the middle of the inner surface of the profile to the center of the cross-section of the body-radiator.

There is a causal relationship between the set of essential features of the proposed device and the achieved technical result (increasing the efficiency of heat transfer from the inner surface of the radiator housing), namely:

- the presence of a longitudinal rib and its direction to the center of the cross-section of the radiator body will provide in the central region of the cross-section of the radiator body:

- an increase in the share of thermal energy transmitted to the longitudinal air flow from all the heat released by the LED module;

- increase in the temperature of the longitudinal air flow;

- increasing the speed and degree of turbulence of the longitudinal air flow.

In addition, an increase in the speed of the longitudinal air flow in the central region will lead to an increase in the value of the lateral air flow entering through the side air gaps of the radiator housing, that is, to an increase in the volume of cooling air passing per unit time through the cross section of the radiator housing.

Thus, the combination of essential features of the claimed device has a direct positive effect on improving the uniformity - temperature, speed and degree of turbulence of the longitudinal air flow, over the entire cross-sectional area of the body. This leads to an increase in the thermal energy transported by the longitudinal air flow in the central region and, therefore, to an increase in the total heat transfer from the inner surface of the radiator housing and, as a consequence, ensures the achievement of the technical result - an increase in the efficiency of heat transfer from the inner surface of the radiator housing to the environment.

As a result, with the operating temperature of the radiator body being equal to that of the prototype, the essential features of the proposed device, by increasing the efficiency of heat transfer, will reduce the weight and overall dimensions of the radiator body.

The essence of the invention is illustrated by graphic materials, which show the design of the housing-radiator with a cross-section in the form of an equilateral polygon.

FIG. 1. A case-radiator of a triangular shape - as a special case of a polygon.

FIG. 2. Cross-section of the lower part of the casing-radiator of a triangular shape.

FIG. 3. Cross-section of the lower part of the casing-radiator in the shape of a square - as a special case of a polygon.

FIG. 4. Cross-section of the lower part of the casing-radiator in the form of a rhombus - as a special case of a polygon.

Implementation of the invention

The heat-conducting body-radiator (Fig. 1) of the LED lamp consists of separate longitudinal profiles 1 of solid cross-section, in the middle of the inner side of which there is a longitudinal rib 2 directed to the center of the cross-section of the body-radiator, and LED light sources 3 are fixed on the outer surface. The planes of the outer surface of the longitudinal profiles 1 in the cross-section of the body form a polygon in the form of an equilateral triangle, as a particular case of execution. The profiles are fastened to each other with connectors 4 with the formation between the longitudinal edges 5 of the adjacent profiles 1 of air gaps 6, the width of which, "B" at the lower end 7 and "C" at the upper end 8, is made in compliance with the inequality B ≤ B.

FIG. 2 shows a cross-section of the lower part of the radiator housing made of separate longitudinal profiles 1, in the middle of the inner side of which there is a longitudinal rib 2, and on the outer side there is an LED light source 3, in the form of an LED matrix, protected by a lens 9. Between the longitudinal edges 5 of adjacent profiles 1, lateral air gaps 6 are provided through which transverse air flow 10 flows from the environment into the interior of the luminaire.

In various designs, the lamp housing-radiator can have a cross-section in the form of an equilateral polygon: triangle, square, rhombus (Fig. 2, Fig. 3, Fig. 4). In addition, the thickness of the longitudinal rib 2, along its height, can be both constant and variable, and the height of the longitudinal rib is made less than the distance to the center of the cross-section of the radiator housing. For the purpose of lateral irradiation inside a bush of plants, a housing design with a cross-section in the form of an equilateral triangle is preferable (Fig. 1, Fig. 2).

The lamp housing-radiator works as follows.

The process of heat exchange of a heat-conducting body with a cross-section in the form of a polygon takes place directly into the environment, both from its inner and outer surfaces. And if heat transfer from the outer surface of the case occurs by natural convection in conditions of unlimited volume, then heat transfer from its inner surface occurs in conditions of a limited volume, and this negatively affects the intensity of the heat transfer process occurring at this surface.

The main influence on the intensity of heat transfer, other things being equal, is exerted by the speed and mode of the flow of the cooling air.

The presence of a longitudinal rib on the inner side of the cross-section of the profile and its direction to the center of the cross-section of the radiator body improves the uniformity of temperature, speed and degree of turbulence of the longitudinal air flow over the entire cross-sectional area of the radiator body by increasing the temperature, speed and degree of turbulence of the longitudinal air flow in its central area. This is achieved due to the presence of longitudinal ribs in the profiles of the radiator housing, which in this area provide:

- an increase in the share of thermal energy transmitted to the longitudinal air flow from the total thermal energy released by the LED module;

- increase in the temperature of the longitudinal air flow;

- an increase in the speed and degree of turbulence of the longitudinal air flow.

In addition, an increase in the speed of the longitudinal air flow in the central region will lead to an increase in the value of the lateral air flow through the side air gaps of the radiator casing, and hence to an increase in the volume of cooling air passing per unit time through the cross section of the radiator casing.

The proposed radiator housing for a LED lamp when used for side lighting inside a bush of tall agricultural plants, due to the highly efficient heat transfer of the radiator housing to the environment, has a lower weight and cost.

At the same time, the temperature of the luminaire body exceeds the ambient temperature in the greenhouse by no more than 15-18 ° C, which provides the plants inside the bush with comfortable growth conditions under side lighting.

The LED luminaire with the proposed radiator housing is structurally simple and therefore reliable when used in protected ground conditions.

The LED luminaire with the proposed radiator housing can be manufactured in a wide power range from 50 to 320 watts and lengths from 400 to 2500 mm.

Claims (1)

Heat-conducting housing-radiator of an LED lamp, made of separate longitudinal solid-section profiles, with at least one LED light source fixed on the outer side of each of them, and the profiles are fastened together with connectors so that the planes of the outer surface of the profiles in the cross-section of the housing form an equilateral polygon , and between the longitudinal edges of the adjacent profiles, air gaps are provided, the width of which, "B" at the lower end and "C" at the upper end, is made in compliance with the inequality B ≤ B, characterized in that in the middle of the inner side of the profile cross-section, a longitudinal a rib directed to the center of the cross-section of the radiator housing.

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