TW201343066A - Automatic controlled mechanism of adjusting the light position by detecting the canopy height of plants - Google Patents

Abstract

This invention is an automatic device applied in the multilayer cultivation shelves in plant factories to maintain the consistent light intensity on the plant canopy. This device could detect the plant height and move up the light source upward automatically to maintain the consistent distance between plants and the light source. The device provides a consistent light environment during the cultivation. It solves the dilemma caused by the traditional design of fixed position of light: light insufficiency caused by the large distance between the light and plant on the early stage, and the possibility of heat injury on the leaves when the plants grow up to reach the surface of light. This devise uses less light tubes to maintain a suitable light intensity for plants and achieves the energy-saving advantage.

Description

Control mechanism that automatically adjusts the height of the artificial light source with the height of the crop

The present invention relates to a device for use in a plant factory, and more particularly to a control mechanism for automatically adjusting the height of an artificial light source with a crop height on a crop cultivation shelf.

In recent years, plant factories have flourished in East Asia. The production and academic circles of Taiwan, Japan, South Korea, and China have invested in researching related technologies. In particular, the completely environmentally-controlled plant factories are not interfered by external environmental conditions and are the mainstream of recent development. However, due to the need to completely replace cheap sunlight with artificial light sources, the high dependence on energy has always been the biggest limitation of a fully controlled plant.

There are many forms of artificial light sources that can be used in plant lighting applications, such as halogen lamps, metal lamps, low-pressure sodium lamps, high-pressure sodium lamps, etc. However, they all have the common problem of high calorific value, especially when light reaches the leaves of the plant with heat. And affect the growth of plants, so there must be a certain height from the crop. In a fully environmentally-controlled plant, because the cost is higher than that of sunlight, all three-dimensional cultivation is attempted to maximize the benefits. Stereoscopic cultivation is required in a limited space, and the height of the shelf is mostly limited to 45 cm, so that these light sources are basically excluded.

The rate of plant photosynthesis is directly dependent on the amount of light that reaches the blade. According to the basic optical principle, the illuminance is inversely proportional to the square of the distance. The farther the light source is from the blade, the less the effective light reaches the leaf surface, so the luminaire should be as close as possible to the blade. However, the lamp is close to the blade but the temperature is too high. In recent years, although the energy-saving fluorescent tube has made great progress, its light is still accompanied by heat. The height of the shelf at 45 cm is almost the limit, and it is difficult to approach it. Foliage. At present, most of the design of the cultivation shelf is fixed directly above the laminate. In the early stage of plant cultivation, the plant type is small, and the light source may be far away from the light source. However, if the number of lamps is increased at this time, the plant type becomes larger when the cultivation is late. The blade may be close to the light source, and the high temperature of the light source may affect the physiology of the plant and even cause blade damage. Excessive amounts of light may also cause physiological disorders. Both et al. (1997) pointed out that the upper limit of the daily illuminating value of lettuce is 17 mol m ^-2 d ^-1 , and excessive light will produce leaf burning.

Light-emitting diode (LED) is the new favorite of lighting in recent years. Due to its high luminous efficiency, low energy consumption and long life, it is regarded as the most potential source for future plant lighting. Its characteristic low surface temperature of the luminescent surface gives it the opportunity to be as close as possible to the foliage of the plant. The purpose of this study is to develop a cultivation shelf that automatically adjusts the height of the lamp with the growth of the plant by utilizing the low-heating characteristics of the LED, so that the LED is as close as possible to the leaf surface, and provides the maximum amount of light with minimum energy consumption.

Light quantity is an important factor that directly affects plant growth patterns and various physiological parameters. In a fully artificial light source type plant factory, all efforts are made to increase the amount of light to meet crop growth requirements, but the energy consumption has always been an urgent problem to be solved. Most of the light sources on the current cultivation shelf can't adjust the height with the growth of the plant. Since the light measurement is inversely proportional to the square of the distance, the artificial light source with a fixed height is easy to cause the plant to be long due to insufficient light in the initial stage of planting.

Completely controlled plant plants are not subject to external environmental conditions and are the mainstream of recent development. However, due to the need to completely replace cheap sunlight with artificial light sources, the high dependence on energy has always been the biggest limitation of a fully controlled plant. In terms of limited energy consumption, the closer the light source is to the plant, the greater the amount of light received by the foliage, which is beneficial to plant growth. However, the lamps will heat up, and the light will reach the leaves of the plants along with the heat, which will affect the growth of the plants. Therefore, there is a need for a mechanism to keep the lamps as close as possible to the foliage to reduce the lamps and energy consumption. But not too close, so as to avoid overheating the leaves and damage the plants.

Accordingly, it is an object of the present invention to provide a control mechanism for automatically adjusting the height of an artificial light source with a crop height on a crop cultivation shelf.

The technical means adopted by the present invention to solve the problems of the prior art is a control mechanism that automatically adjusts the height of the artificial light source with the height of the crop. As shown in the first figure, the cultivation shelf comprises at least one plant bed, a light stand and a control mechanism, the plant bed is loaded with at least one crop, the light stand is provided with at least one light fixture (such as LED), the light stand and The control mechanism is correspondingly disposed on the plant bed, wherein the control mechanism comprises: a crop height sensing unit, which is a set of two diagonally mounted transparent photoelectric switches, which can sense the height of the crop; The rack height adjustment actuating unit comprises an AC motor, a pulley and a speed reducer, and is movably connected to the lamp holder and can adjust the distance between the lamp holder and the crop. After the height sensing unit of the crop senses the height of the crop, the height adjustment unit of the light fixture can adjust the distance between the light fixture and the crop to maintain the predetermined distance between the light fixture and the crop, so that the crop can be Accept a predetermined amount of light.

In addition, in another embodiment of the control mechanism, the crop height sensing unit may also be a reciprocating scanning detecting unit including at least one photo-electrical sensor (reflective photoelectric switch) and a reciprocating actuating mechanism (reciprocating motor and Screw) can be used for reciprocal scanning to perceive the height of the cultivated crop in the cultivation space. At the same time, the control mechanism further includes an arithmetic control unit electrically connected to the crop height sensing unit and the lamp height adjusting actuating unit, wherein the computing control unit can calculate the proportion of each reciprocating scan scan interrupt signal. And according to whether to determine whether to activate the lamp holder height adjustment actuation unit.

Through the technical means adopted by the present invention, a cultivation shelf capable of automatically adjusting the height of the artificial light source with the growth of the plant height is provided, and the height of the plant blade crown is detected by the penetrating photoelectric switch, and when the plant grows to block the photoelectric switch The lamp is moved up, maintaining the light source 5 cm from the canopy and the amount of light 200 μmol m ^-2 s ^-1 . The experimental results show that the device of the invention plants lettuce with less lamps, and its growth is not affected, which can effectively reduce the number of lamps and reduce the lighting energy consumption by 17%. Since the invention can effectively reduce the lighting fixtures and energy consumption and maintain the crop quality with a simple mechanism, it has practical application value and development potential for application in artificial cultivation.

Embodiment 1: A control mechanism capable of automatically adjusting the height of the artificial light source with the height of the crop plant

Referring to the first figure, the present invention discloses a control mechanism that automatically adjusts the height of the artificial light source with the height of the crop. As shown in the first figure, the cultivation shelf 100 comprises at least one plant bed 1, a light stand 2 and a control mechanism 3, the plant bed 1 is loaded with at least one crop 11, and the light stand 2 is provided with at least one light fixture 21 ( For example, LED), the lamp holder 2 and the control mechanism 3 are correspondingly disposed on the plant bed 1, characterized in that the control mechanism 3 comprises: a crop height sensing unit 31, which is a penetration of two sets of diagonally fixed installations. The photoelectric switch 31 is configured to sense the height of the crop 11; a light stand height adjustment actuating unit 32 includes an AC motor 321, a pulley 322 and a reducer 323 movably connected to the light stand 2 The distance between the lamp holder 2 and the crop 11 can be adjusted. After the crop height sensing unit 31 senses the height of the crop 11, the height adjustment actuating unit 32 can adjust the distance between the light fixture 2 and the crop 11 to maintain the light fixture 21 and the crop 11 The predetermined distance allows the crop 11 to accept a predetermined amount of light.

In addition, as another embodiment of the cultivation shelf 100a shown in the third to fourth embodiments, the crop height sensing unit 31a may also be a reciprocating scanning detection unit including a reflective photoelectric switch 313, a screw 314, and a reciprocating motor 315. The utility model comprises at least one photoinductor (reflective photoelectric switch 313) disposed on the screw 314, and a reciprocating actuating mechanism (screw 314 and reciprocating motor 315), which can rotate the screw 314 forward and reverse to make the reflective type The photoelectric switch 313 is moved left and right for scanning, and can be used for reciprocating scanning to sense the height of the cultivated crop in the cultivation space. At the same time, the control mechanism further comprises an arithmetic control unit (not shown) electrically connected to the crop height sensing unit and the lamp height adjusting actuating unit, wherein the computing control unit can calculate each reciprocating scan cover. The ratio of the signal is broken, and it is judged whether or not the lamp height adjustment actuating unit is actuated. As shown in the fourth figure, when there are blades in the scanning angle, the signal is output and the ratio of the interception in the stroke is calculated to indicate the height of the whole plant. When the blocking ratio is greater than the preset value (for example, more than 50% of the strokes are Interrupted), indicating that the plant is too high and the luminaire must be moved up. Compared with the embodiment shown in the first to second figures, the present embodiment can represent the height of the whole plant more than the diagonal penetrating photoelectric switch, and can be closer to the actual condition of the overall growth of the plant and react accordingly.

Experimental equipment and methods

The basic idea of the present invention is to design a device capable of automatically adjusting the height of the lamp according to the growth of the plant, so that the lamp can be kept at a fixed distance above the blade crown of the plant, and the height of the plant canopy can be detected by using a photoelectric switch, and the sensor will be covered when the plant grows to the blade. At the time of the break, the luminaire needs to be moved up again to maintain the fixed distance between the light source and the leaf crown, and the light field of the height of the leaf crown is maintained consistent.

The cultivating shelf 100 shown in the first figure is composed of a screw-free universal angle steel with a shelf size of 127 cm × 50 cm × 195 cm and a four-layer cultivation planting bed with a spacing of 36 cm. Lettuce was planted in a PVC hydroponic tank on each floor with a depth of 7 cm. The size of the floating plate in the sink is 110 cm × 50 cm. There are 4 rows of cultivation holes staggered on the floating plate. A total of 22 plants can be cultivated and the plant spacing is 17 cm. The bottom of the shelf is provided with a liquid circulation tank (not shown), and the nutrient solution is sent to the uppermost layer by a submersible pump, and flows naturally through the layers with gravity to return to the nutrient tank.

As shown in the first figure, it uses a 200W forward-reversible single-phase 220V AC motor 321 to drive the shaft of the reducer 323. Two ropes 33 (nylon ropes) are respectively extended to the left and right sides at both ends of the shaft, and are connected to both sides of the lamp holder 2. When the rotating shaft rotates, the retracting of the rope 33 can raise or lower the height of all the lamps 21 in the cultivation shelf 100.

Also referring to the second figure, which shows a schematic diagram of the present invention for detecting crop height. Two sets of transmissive photoelectric switches (MT-6MXP, Fotok, Taiwan) 311, 312 are installed diagonally in the four corners below the lamp holder, and the detection height is 5 cm from the lamp. When the plant height interrupts any set of detected infrared light (IR), the occlusion signal is immediately transmitted to the programmable controller and the motor is started to rotate, and the luminaire is slightly moved up to the occlusion signal to stop, so that the luminaire height is fixed and maintained. 5 cm above the crown.

Example 2: Effect of cultivation shelf on the growth of lettuce

In the present embodiment, the cultivation rack which can automatically adjust the height of the artificial light source according to the height growth of the crop plant is used to explore the influence on the growth of the crop (lettuce), and the apparatus used in the embodiment (for example, the number and type of LEDs), The structures and crop species are merely illustrative and are not intended to limit the scope of the invention.

The experimental light source is a 24W cold white LED T8 tube (5500K, LEDplux, Taiwan) with indoor illumination. Install a different number of LED tubes on the moving light stand for two kinds of light processing: (1) 5 LED tubes (5M), providing 200 μmol m ^-2 s ^-1 light at 5 cm below the lamp (2) Four LED tubes (4M) provide a light quantity of 150 μmol m ^-2 s ^-1 , and the distance between the above two treatment sources and the top of the plant is 5 cm. The experiment is based on the treatment of the traditional fixed light source height: (3) 6 LED tubes (6F) and (4) 5 LED tubes (5F), the light source is 25 cm away from the cultivation float. The fifth graph shows the average amount of light at each leaf crown height for each light quantity treatment. The light fields of the treatment groups 5M and 4M of the movable lamp are maintained at 200 and 150 μmol m ^-2 s ^-1 , respectively, during cultivation. In the treatment group with fixed lamp height, the plant height of lettuce seedlings was about 5 cm at the initial stage of cultivation, and the amount of light provided by the 6F treatment group at the height of the leaf crown was 165 μmol m ^-2 s ^-1 . Before harvesting, the plant height grew to 11 cm, and the height of the canopy height was about 200 μmol m ^-2 s ^-1 . 5F with the treatment group during the experiment height growth, Ye Guanguang amount of 140 μmol m ^-2 s ^-1 lift 185 μmol m ^-2 s ^-1.

The varieties of this test were selected from Boston lettuce ( Lactuca sativa var. capitata L.) and the seeds were purchased from Taiwan Jiayu Seed Co., Ltd. Lettuce cultivation facilities and methods refer to the process of Zhang et al. (2010). The day/night temperature of the environmental control room is set at 25/18 °C, and the carbon dioxide concentration is maintained at 1,200 ± 100 ppm during the day, and is not replenished at night. The lettuce was cultivated in a four-layer three-dimensional hydroponic cultivation layer. The cultivation liquid was used in Hyponex (USA), the EC value was maintained at 1.2 mS cm ^-1 , and the pH was 6.0.

The seeds in which the seeds after 5 hours of soaking were transplanted were cultivated for 3 days at an ambient temperature of 20 °C. After germination, it was moved to the seedling bed of the environmental control room, and the light amount was 125 μmol m ^-2 s ^-1 . After the 21st day, it was moved into a growing bed and the experiment was started. At this time, the average fresh weight of the plants was 0.51±0.13 g, the dry weight was 0.43±0.01 g, the number of leaves was 4.9±0.5, and the leaf area was 17.47±4.55 cm ² . The trial lasted for 14 days and was harvested on day 35.

Determination and Analysis of Physiological Parameters of Lettuce Method for determining photosynthesis rate of lettuce leaves

On the 31st day after sowing, 5 lettuces were selected on each of the treated cultivation racks, and each piece of unobstructed mature upper leaves was selected, and photosynthesis was measured by photosynthesis analyzer (LI-6400, Li-COR, USA). rate. Due to the rhythmic changes in photosynthesis, all treatments need to be measured during the most vigorous period of photosynthesis between 10:30 and 12:00.

Method for measuring fresh weight and dry weight of lettuce

After the test, all the 22 lettuces in each layer were harvested, and the shoots were cut off, and the fresh weight of the shoots was measured with an electronic balance. After measuring the total leaf area, the lettuce was dried at 75 ° C for at least 72 hours to constant weight, and the dry weight was measured with an electronic balance.

Method for measuring total leaf area of lettuce

All fully expanded mature leaves in each lettuce were selected and measured in a leaf area meter (LI-3000, Li-COR, USA) in cm ² .

Method for analyzing chlorophyll content of lettuce

Five strains of lettuce were randomly selected for each treatment, and 1 g of the upper leaves were cut out. After immersing in liquid nitrogen in a mortar, 20 mL of 80% acetone was added. The extract was poured into an Erlenmeyer flask, and the pigment remaining in the mortar was washed with 10 mL of 80% acetone. All acetone extracts were placed in the same conical flask and diluted to 80% acetone to a total volume of 100. mL. The absorbance was measured at a wavelength of 663 nm and 646 nm in a spectrophotometer (Hsu, 2011).

The chlorophyll a and b contents are shown in formulas (1) and (2).

among them

Cha.=leaf chlorophyll a content (mg g ^-1 )

Chb.=leaf chlorophyll b content (mg g ^-1 )

A ₆₆₃ : absorbance of the sample at a wavelength of ₆₆₃ nm

A ₆₄₆ : absorbance of the sample at a wavelength of ₆₄₆ nm

V: volume of 80% acetone extract (ml)

W: sample weight (g)

Soluble carbohydrate content analysis

The method of Fu (2009) was modified, and 4 dried lettuces were randomly selected and ground in a homogenizer. The dry weight of the powder was weighed 1 g, 80 mL of 80% alcohol was added, and after 30 minutes in a water bath at 80 ° C, the residue was filtered. The residue was repeated in the same manner as above, and the extraction was repeated three times. The filtrates were combined three times, and the alcohol was removed and quantified by PVP to 100 mL. Dilute to the appropriate concentration.

Take 2 ml of the diluted solution, add 4 ml of anthrone solution to the cold water bath, mix well, put it into boiling water at 100 ° C for 6.5 minutes, then rapidly cool in an ice bath, and measure it at a wavelength of 625 nm in a spectrophotometer. The sample glucose content was measured by comparison with an anhydrous glucose standard concentration calibration curve. Substituting formula (3) to determine the carbohydrate content.

among them

CHO.: Leaf carbohydrate content (mg g ^-1 )

Glu.: Glucose content (ppm)

D.W: dry weight of sample (g)

This experiment used the SAS software for Duncan's multivariate domain statistical analysis (p<0.05).

Results and discussion

Table 1 shows the results of lettuce experiments with different light amounts. The fresh light weight of the treatment group (5M and 6F) was significantly better than the low light treatment group (4M and 5F). In the same 5 tubes, the dry weight of the mobile luminaire 5M treatment group is significantly better than the fixed luminaire treatment group 5F. The sixth to sixth B-pictures show the growth of lettuce in the 35th day of cultivation. The leaf shape of the 5M and 6F treatment groups is tighter, and the leafballs of the 4M treatment group are smaller than the other three groups.

Table 1 Results of lettuce experiment with different light amount treatment

Plants use light as a source of energy to drive photosynthesis. The effects of light on plants can be roughly divided into three directions: light quantity, light quality and photoperiod. In particular, light quantity has a great influence on plant type development, biomass accumulation and photosynthesis. Park et al. (1999) pointed out that lettuce cultivation at a CO ₂ concentration of 1000 ppm increased the light amount to 200 to 150 μmol m ^-2 s ^-1 to increase the fresh weight of lettuce and increase the accumulation rate of carbon dioxide. The photosynthetic rate data in Table 1 shows that the photosynthetic rate of the 5F treatment is lower than that of the other treatment groups. Comparing the average light quantity of the leaf crown in the harvesting stage with different light quantity treatment in the fifth figure, it can be found that the light quantity of 6F is higher than 5F, and the photosynthetic rate has a similar trend.

The fifth graph only shows the relationship between plant height and leaf crown light, and does not show its growth rate. The growth model of a creature is generally regarded as an exponential model, but nonlinear. This means that the time required for plant heights from 5 cm to 8 cm will be much higher than that of 8F to 11 cm, ie 5F and 6F treated lettuce, which may be at the lowest in the early stage of the plant. The amount of light is maintained at about 140 and 165 μmol m ^-2 s ^-1 for a period of time. It is raised to 185 and 200 μmol m ^-2 s ^-1 until the latter period. In the 4M and 5M treatment groups of mobile luminaires, the amount of leaf crown in the whole experiment was maintained at 150 and 200 μmol m ^-2 s ^-1 . When calculating the cumulative light amount during the 14-day cultivation period, the 6M treatment group was significantly larger than the other 3 Processing. Although 5M was only maintained at 150 μmol m ^-2 s ^-1 , its photosynthetic rate was significantly better than that of 5F treatment group, which should be caused by the cumulative light quantity greater than 5F treatment group. Wang et al. (2006) studied the increase of light quantity in American chestnut trees, the photosynthesis of plants, the increase of stomatal conductance, and the accumulation of photosynthetic products in plant leaves, which in turn increased the biomass. Similar results were found in this experiment. The 5M treatment group had the highest average carbohydrate content and the highest average dry weight, indicating that maintaining a higher light amount during the cultivation process significantly increased lettuce growth.

Plants can be generally classified into positive plants and negative plants according to the ratio of chlorophyll a/b (positive plant chlorophyll a/b ratio is about 3, negative plants are about 2), and increased light amount can increase photosynthesis efficiency and increase plant growth for positive plants. This experiment found that there was no significant difference in the chlorophyll a content of each treatment, but the treatment of 5M significantly increased the content of chlorophyll b (Table 1). At the same chlorophyll a content, a moderate increase in chlorophyll b can increase the utilization efficiency of plant photosynthesis, because chlorophyll b acts as a plant photosynthesis photo-enhancing pigment and protective pigment-binding protein to avoid protein senescence (Michel et al., 1983).

Calculating the energy efficiency makes it possible to compare the economic benefits of each treatment. In calculating the energy consumption ratio of the energy required per unit weight, the lighting energy consumption during the pre-experimental seedling period should also be included. The four treated lettuce seedlings supplied in this study were all cultivated in the same seedling bed, with the aim of having consistent experimental materials at the beginning of the experiment. The seedlings lasted for 21 days, using 4 24W LED tubes with a photoperiod of 16 h and a power consumption of 32.26 kW h. The average power consumption per treatment during the nursery period was 8.07 kW h. In the experiment, the total use time of the 200 W AC motor of the lifting lamp was only about 30 seconds, and the photoelectric switch consumes much less power than the lamp, so it does not count the power consumption. In the table, the weight of each layer using 6 lamps (6F) is equivalent to that of a mobile luminaire (5M) using 5 lamps. The mobile lamp (4M) treatment group with 4 lamps has the lowest energy consumption but the least weight. It can be seen from the comparison of the energy consumption ratio that the 5F and 6F of the fixed lamps have almost the same energy consumption, the increase of the lamps does not increase the output, and the energy consumption ratio is higher than that of the mobile lamps. The 5 kW mobile luminaire (5M) treatment group has the same harvest weight as 6F, but consumes only 83% of 6F, which saves 17% of electricity. The energy consumption per 100 g of lettuce is 1.72 kW h. The lowest of all treatments. 4 lamps with mobile lamps (4M), although the power consumption is low, but the output is also low, the energy consumption ratio is still higher than the 5M treatment group, and the harvested plant type is smaller, the market sells poorly, reducing One lamp has no benefit.

Table 2 Comparison of energy consumption of different light treatments

^x power consumption (kW h) = lamp power (24 W) × number of lights × light cycle (16h / d) × days (14 d) / 1000

^y total weight of 22 plants per layer

^z energy consumption ratio = (power consumption +8.07) / harvest weight (100g)

Among them, 8.07 (kW h) was the electrical energy consumed by each of the 22 lettuces treated under the same seedling conditions for 21 days.

in conclusion

Through the invention, the cultivation shelf capable of automatically adjusting the artificial light source height with the height of the crop plant can be maintained at 5 cm above the canopy with 5 LED tubes on a 127 cm×50 cm plant bed, providing 200 μmol m ^-2 s ^-1 light field. The cultivation effect of lettuce was not significantly different from that of 6 LED tubes fixed at 25 cm above the cultivation float. In terms of energy consumption, this design can save 17% of lighting energy.

It can be seen from the above embodiments that the control mechanism provided by the present invention for automatically adjusting the height of the artificial light source with the height of the crop has industrial value, but the above description is only for the preferred embodiment of the present invention. Other modifications of the art may be made by those skilled in the art, and such modifications are still within the spirit of the invention and the scope of the invention as defined below.

100, 100a. . . Cultivation shelf

1. . . Plant bed

11. . . crop

2. . . Light stand

twenty one. . . Lamp

3. . . Control mechanism

31, 31a. . . Crop height perception unit

311, 312. . . Penetrating photoelectric switch

313. . . Reflective photoelectric switch

314. . . Screw

315. . . Reciprocating motor

32. . . Stand height adjustment actuation unit

321. . . AC motor

322. . . pulley

323. . . Reducer

33. . . rope

The first figure shows the control mechanism of the invention for automatically adjusting the height of the artificial light source with the height of the crop;

The second figure shows a schematic diagram of the invention for detecting the height of a crop;

The third figure shows another embodiment of the control mechanism of the present invention for automatically adjusting the height of the artificial light source with the height of the crop;

The fourth figure shows a schematic diagram of the embodiment shown in the third figure for detecting the height of the crop;

The fifth graph shows the average amount of light in the canopy of the different light treatments during the harvesting phase;

Figures 6 to 6B show the growth of lettuce treated at the 35th day of cultivation.

100. . . Cultivation shelf

1. . . Plant bed

11. . . crop

2. . . Light stand

twenty one. . . Lamp

3. . . Control mechanism

31. . . Crop height perception unit

311, 312. . . Penetrating photoelectric switch

32. . . Stand height adjustment actuation unit

321. . . AC motor

322. . . pulley

323. . . Reducer

33. . . rope

Claims (8)

A control mechanism capable of automatically adjusting the height of an artificial light source according to a plant height, which can be applied to a cultivation shelf, the cultivation shelf comprising at least one plant bed, a light stand and a control mechanism, the plant bed being loaded with at least one a light fixture provided with at least one light fixture, the control mechanism being correspondingly disposed on the plant bed, wherein the control mechanism comprises: a crop height sensing unit for sensing the height of the crop; The movable unit is movably connected to the light stand and can adjust the distance between the light stand and the crop; wherein the height adjustment unit of the crop height senses the height of the crop, the light stand height adjustment actuation unit can be The distance between the light fixture and the crop is adjusted to maintain the luminaire at a predetermined distance from the crop so that the crop can receive a predetermined amount of light. The control mechanism of claim 1, wherein the crop height sensing unit is a reciprocating scanning detecting unit, comprising at least one photo-electrical sensor and a reciprocating actuating mechanism for reciprocating scanning sensing The cultivation crop height of the cultivation space. The control mechanism of claim 2, wherein the reciprocating scan detecting unit comprises a reciprocating motor and a screw. The control mechanism of claim 2, wherein the reciprocating scan detecting unit comprises a reciprocating motor and a screw. The photo-electrical sensor is a reflective photoelectric switch. The control mechanism of claim 2, wherein the control mechanism further comprises an operation control unit electrically connected to the crop height sensing unit and the lamp height adjustment actuation unit, wherein the operation control unit is The ratio of each of the reciprocating stroke scan interruption signals is integrated, and it is judged whether or not the lamp holder height adjustment actuation unit is actuated. The control mechanism of claim 1, wherein the crop height sensing unit is a set of two diagonally mounted transmissive photoelectric switches. The control mechanism of claim 1, wherein the luminaire is an LED. The control mechanism of claim 1, wherein the lamp height adjustment actuation unit comprises an AC motor, a pulley and a reducer.