JPH11168993A - Plant growing box - Google Patents

Abstract

(57) [Problem] To provide a plant growing box capable of adjusting the amount of light applied to a plant to an arbitrary value while using a microwave lamp having a high light intensity. In a plant growing box for growing plants by irradiating the plants with artificial light, a microwave lamp is used as an artificial light source, and the light emitted from the microwave lamp is dimmed on an optical path until reaching the plants. The device 30 is arranged, and the dimming device 3
By adjusting the angle of the light-blocking blade 31 of 0, the light amount can be reduced to an arbitrary value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a plant growing box for growing plants by irradiating the plants with artificial light.

[0002]

2. Description of the Related Art Hitherto, a light source used in a plant growing box for promoting plant growth by irradiating artificial light has been an HID lamp (metal halide lamp) or the like. In recent years, microwave lamps have attracted attention as their light sources because of their high light intensity as in the daytime. For example, when the floor area on which the plants are arranged is 1 square meter, one microwave lamp of 1 KW is turned on to generate about 30,000 lux (about 4 lux).
Illuminance (photon flux density) of 30 micromol / square meter / second) can be obtained.

[0003] When such a microwave lamp is used as a light source, conventionally, the number of microwave lamps to be turned on is increased or decreased to adjust the light intensity applied to the plant. For example, the brightness is adjusted in two stages by turning on both of the two microwave lamps or turning on only one.

[0004]

However, since the microwave lamp is extremely bright, there is a problem that, even if the number of lighting is reduced to only one, it is too bright in the initial stage (young plant) of the plant growing stage. .

[0005] In addition, C3 and C4 plants open stomata upon receiving light, take in carbon dioxide gas in the air, perform photosynthesis, and release water by transpiration. It takes several minutes to several tens of minutes. In such plants, if strong light is applied before the pores are sufficiently opened, leaf tissue may be damaged by the influence of active oxygen.

[0006] In the conventional HID lamp, 10 hours after the start of lighting
Since the brightness gradually increased from minutes to 20 minutes, the amount of light increased in accordance with the opening of the pores. However, the microwave lamp brightened instantaneously (3 to 5 seconds). For this reason, even if the initial lighting number is limited to one, there is a possibility that the plant cannot respond and may be damaged.

[0007] The present invention has been made in view of such problems of the prior art, and uses a microwave lamp to grow a plant capable of adjusting the amount of light applied to the plant to an arbitrary value. It is intended to provide boxes.

[0008]

The gist of the present invention to achieve the above object lies in the following inventions. [1] In a plant growing box for growing plants by irradiating the plants with artificial light, a microwave lamp (23) for emitting light for irradiating the plants to be grown and light emitted from the microwave lamp (23) are A dimming means (30) arranged on an optical path until reaching the plant, wherein the amount of light reaching the plant among the light emitted from the microwave lamp (23) is determined by the dimming means (30). 30) A plant growing box characterized by being reduced to an arbitrary value according to 30).

[2] The dimming means (30) includes a light-shielding wing (31) rotatable from a state parallel to the light toward the plant to a state perpendicular to the light, and the light-shielding wing (31). A motor (32) for rotating the light-shielding wings (31) to change the angle of the light-shielding wings (31) to reach the plants among the light emitted from the microwave lamp (23). The plant growing box according to [1], wherein the amount of light emitted is reduced to an arbitrary value.

[3] The dimming means (30) includes a plurality of dimming filters (51) having different light transmittances and dimming filter inserting means for moving and inserting the dimming filter (51) in the optical path. (53), wherein the amount of light to be reduced is changed in multiple stages by selecting the type and number of neutral density filters (51) to be inserted into the optical path [1]. The described plant growing box.

[4] The dimming means (30) includes a neutral filter (81) having a density that changes from a high light transmittance state to a low light transmittance state, and one of the neutral filter (81) that moves the neutral filter (81). Filter moving means (72, 82) for inserting a region of the section into the optical path, wherein the amount of light to be reduced is changed by selecting the region to be inserted into the optical path. The plant growing box according to [1].

[5] In a plant growing box for irradiating plants with artificial light, a microwave lamp (23) for emitting light for irradiating the plants to be grown and the microwave lamp (23) are turned on. Lamp driving circuit (10
0, 200), and the lamp driving circuit (100,
200) A plant growing box characterized in that the amount of light emitted from the microwave lamp (23) can be adjusted to an arbitrary value.

[6] The lamp drive circuit (100, 20)
0) changes the ratio of the time for applying a predetermined high voltage between the cathode and the anode of the microwave electron tube (21) of the microwave lamp (23) in a unit time to change the microwave lamp (23). 23) The plant growing box according to [5], wherein the light emitting amount is adjusted.

[7] The lamp driving circuit (100) comprises:
AC for turning on and off an AC supplied to a primary side of a transformer (101) for generating a high voltage applied between a cathode and an anode of a microwave electron tube (21) of the microwave lamp (23). Power adjustment circuit (103, 10
The plant growing box according to [5], wherein the light emitting amount of the microwave lamp (23) is adjusted by increasing / decreasing a ratio of the number of cycles of the hollowing out.

[8] The lamp driving circuit (200) comprises:
The microwave lamp (23) includes a PWM inverter circuit (205, 206) for generating a high voltage to be applied between a cathode and an anode of the microwave electron tube (21), and changes a width of a generated pulse. The plant growing box according to [5], wherein the amount of light emitted from the microwave lamp (23) is adjusted by the method.

The present invention operates as follows. A dimming means (30) is arranged on the optical path between the microwave lamp (23) that emits light and the plant to be grown, and the light from the microwave lamp (23) that reaches the plant is reduced. The amount is reduced to an arbitrary value by the dimming means (30). Thereby, the light quantity irradiated on the plant can be adjusted to an arbitrary value without changing the light quantity itself of the microwave lamp (23), and the appropriate intensity can be adjusted according to the growing stage of the plant and the opening of the pores. Light can be applied to the plant.

For example, a light-blocking wing (31) rotatable from a state parallel to the light directed toward the plant to a state perpendicular to the light.
And a motor (32) for rotating the light-shielding wing (31). The angle of the light-shielding wing (31) is changed by the motor (32), so that the light from the microwave lamp (23) is emitted. The light that reaches the plant among the light that has been reduced can be used as the light reduction means (30).

[0018] Further, it has a plurality of neutral density filters (51) having different light transmittances, and neutral density filter inserting means (53) for moving and inserting the neutral density filter (51) in the optical path. A device that changes the amount of light to be reduced in multiple stages by selecting the type and the number of the light reduction filters (51) to be inserted may be used as the light reduction unit (30). As the neutral density filter (51), for example, a filter that dims 50%, a filter that dims 25%, and 12.5
If three types of light that are reduced by percent are prepared, the light amount can be adjusted in eight steps in total, including the case where the neutral density filter (51) is not inserted, by combining them.

Furthermore, a neutral filter (8) having a density that changes from a high light transmittance state to a low light transmittance state.
1) and a filter moving means (82) for moving the neutral filter (81) and inserting a part of the area into the optical path, and selecting which density area is to be inserted into the optical path. Thus, a dimming means (30) for changing the amount of light to be reduced can be used. In addition, if the neutral filter (81) having a gradation in which the density continuously changes is used, the amount of light reaching the plant can be continuously and continuously changed.

In addition, the amount of light emitted from the microwave lamp (23) may be electrically adjusted. That is, the light emission amount is adjusted to an arbitrary value by the lamp driving circuits (100, 200) for driving the microwave lamp (23). This makes it possible to finely adjust the light intensity from an extremely low light intensity state as compared with the case where the light intensity is adjusted by the number of lighting of the microwave lamps (23), and to provide an appropriate intensity according to the plant growing stage and the opening of the pores. Light can be applied to the plants. Also, compared to the mechanical type,
It is possible to reduce the size and simplify the device configuration.

For example, by changing the ratio per unit time of applying a predetermined high voltage between the cathode and the anode of the microwave electron tube (21) of the microwave lamp (23), the microwave lamp ( 23) Dimming the light emission amount. Since the microwave electron tube (21) used for the microwave lamp (23) does not oscillate when the applied voltage becomes lower than a certain value, it is difficult to lower the peak value of the voltage to lower the light emission amount.

On the other hand, flickering occurs when the voltage is turned on and off, but this has almost no effect on the growth of plants. Therefore, by controlling the ratio of the time during which the high voltage is applied during the unit time, it is possible to maintain the peak voltage and secure the oscillating state while adjusting the light emission amount of the microwave lamp (23). it can.

For example, an AC power adjusting circuit (ON / OFF control of AC supplied to a primary side of a transformer (101) for generating a high voltage applied between a cathode and an anode of a microwave electron tube (21). 103, 104), the light emission amount of the microwave lamp (23) is adjusted by increasing or decreasing the ratio of the number of cycles for hollowing out. Such a lamp driving circuit (100, 200) can be constituted by a triac and its trigger circuit.

Further, a lamp driving circuit (100, 200)
Alternatively, the light emission amount of the microwave lamp (23) may be adjusted by using a PWM inverter circuit (205, 206) and changing the width or the duty ratio of the generated pulse.

In addition, the amount of light emission may be adjusted by controlling the heater current of the microwave electron tube (21) (magnetron or the like). Alternatively, a voltage substantially equal to the oscillation start voltage of the microwave electron tube (21) may be applied as a bias voltage, and the amount of light emission may be adjusted by increasing or decreasing the voltage superimposed on the bias voltage.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Various embodiments of the present invention will be described below with reference to the drawings. FIG. 2 shows a cross section of the plant growing box 10 according to various embodiments of the present invention. The plant growing box 10 is divided by a partition wall 11 and a bottom plate 12 having a large number of air holes into a growing room 13 for storing plants to be grown and a machine room 14. Training room 13
A light irradiating device 20 for irradiating artificial light to a plant to be grown is disposed in a ceiling portion of the, and a dimming device 30 for adjusting a light amount is provided immediately below the light irradiating device 20.

The light irradiation device 20 includes a microwave lamp 23
Is used for the light source. The microwave lamp 23 has a light spectrum distribution equivalent to that of sunlight, and can obtain a high light intensity as in the midday of summer in Japan.

In the machine room 14, a humidifier 15, a blower 16 and the like are arranged for controlling the humidity and temperature in the growing room 13. The air blown out by the blower 16 flows into the growth chamber 13 through a number of air holes provided in the bottom plate 12, and the air holes 17 formed in the upper part of the partition wall 11.
And returns to the machine room 14 side to circulate.

FIG. 1 shows a light irradiation device 20 and a light reduction device 30 according to the first embodiment. The light irradiation device 20 includes a magnetron 21 as a microwave electron tube.
And a lamp driving circuit 22 for driving the magnetron 21
A microwave lamp 23 as a light emitting sphere, a microwave shielding screen 24, a light reflecting shade 25, and a cooling unit 26.
And

The lamp drive circuit 22 is a circuit that generates a high DC voltage of 3.5 to 4.2 kilovolts from a single-phase AC voltage of 200 volts. The magnetron 21 oscillates when a high DC voltage is applied from the lamp drive circuit 22, and generates a microwave with a velocity-modulated electron flow. In this case, the magnetron 21 generates a microwave having a frequency of 2.45 GHz. Has become. The microwave lamp 23 has a light reflection shade 25.
The polar molecules, such as sulfur, sealed in a quartz glass bulb are heated by the microwaves guided from the base of the above to become a plasma state and emit plasma.

The microwave shielding screen 24 has a function of electromagnetically shielding microwaves from leaking outside. The cooling unit 26 has a function of sending cooling air toward the microwave lamp 23 and rotating the microwave lamp 23 so that the cooling air uniformly hits the microwave lamp 23. The microwave lamp 23 is a light source that can be regarded as a point light source.
It is arranged at five focal points and emits substantially parallel light toward the plant.

The light-reducing device 30 includes a number of light-shielding blades 31 rotatable from a state parallel to the light emitted from the light irradiation device 20 toward the plant to a state perpendicular to the light, and the light-shielding blades 3.
1 is rotated by a motor 32. By changing the angle of the light-shielding wings 31 by the motor 32, the amount of light reaching the plant to be grown out of the light emitted from the microwave lamp 23 is reduced to an arbitrary value.

FIG. 3 shows the dimmer 30 in more detail. The light shielding blades 31 each have a rectangular plate shape, and include a rotation shaft 33 provided at the center in the width direction and extending in the longitudinal direction. A bevel gear 34 is attached to an end of the rotating shaft 33. The drive shaft 35 that is driven to rotate by the motor 32 is arranged perpendicular to each of the rotation shafts 33, and a bevel gear 36 is attached so as to mesh with each bevel gear 34. Bevel gear 36
Are mounted one by one in the opposite direction, and the drive shaft 35
Is rotated in a predetermined direction, so that the adjacent light shielding blades 31 rotate in directions opposite to each other.

Next, the operation of the first embodiment will be described. FIG. 4 shows the light irradiation device 20 and the dimming device 30 as viewed from the lower side where the plant to be grown is arranged. When the light-shielding wings 31 of the dimming device 30 are set in an open state in which the light-shading wings 31 are substantially parallel to light, most of the light from the microwave lamp 23 reaches the plants without being blocked by the light-shielding wings 31. On the other hand, when the light-shielding wings 31 are arranged in a closed state so as to be perpendicular to the light as shown in FIG. 5, most of the light from the microwave lamp 23 is shielded by the light-shielding wings 31 and reaches the plants. The amount of light can be reduced.

When a high DC voltage is applied from the lamp drive circuit 22, the microwave lamp 23 reaches the final brightness in 3 to 5 seconds. For example, when the floor area on which the plants are arranged is 1 square meter, if one microwave lamp 23 of 1 KW is turned on, it takes about 3 seconds in a few seconds after the start of lighting.
An illuminance (photon flux density) of 000 lux (about 430 micromol / m 2 / sec) is obtained. When it is not desired to irradiate such strong light, by adjusting the angle of the light shielding wings 31, it is possible to arbitrarily reduce the amount of light passing through the light reduction device 30, that is, the amount of light reaching the plants.
Thereby, it is possible to irradiate light having an intensity suitable for a plant growing stage.

When light irradiation from the light irradiation device 20 to the plant is started, the light-shielding wings 31 are gradually opened from the closed state over 10 to 20 minutes to obtain light intensity corresponding to the growth stage. The light-blocking wings 31 are finally stopped at the given angle.

FIG. 6 shows a change in the degree of opening of the pores from the start of the light irradiation and a change in the intensity of light emitted from the light irradiation device 20 to the plant. When C3 and C4 plants receive light, they open pores, take in carbon dioxide in the air, perform photosynthesis, and release water by transpiration.
As shown by the dashed line 41 in FIG. 6, it takes several minutes to several tens of minutes from the start of receiving light until the pores are fully opened. If such plants are exposed to strong light before their pores are sufficiently opened, leaf tissue may be damaged by the influence of active oxygen. In addition, if transpiration is suppressed, leaf temperature may increase, causing damage.

Therefore, by driving the motor 32 at an extremely low speed by proportional control or the like, or by reducing the speed by a reduction gear, the light-shielding blade 31 is gradually opened from ten minutes to several tens minutes, as shown by a solid line 42 in FIG. Thus, the light intensity reaching the plant is controlled so as to gradually increase. Thus, the plant is not irradiated with strong light before the pores are sufficiently opened, and no damage is caused to the leaf tissue or the leaf temperature is increased.

Further, if the light intensity is not increased linearly but is gradually increased as shown by a dotted line 43 in FIG. Light irradiation can be started.

FIG. 7 shows a second embodiment.
Here, instead of the dimming device 30, a dimming device 50 configured to reduce the amount of light by a dimming filter is used.
The light reduction device 50 includes three light reduction filters 51 a, 51 b, and 51 c having different light transmittances and the light from the storage box 52 to the front of the light reflection shade 25, that is, the light from the microwave lamp 23 toward the plant. And a filter drive mechanism 53 that slides on the road.

The filter driving mechanism 53 has a motor inside. When the motor is rotated forward, the respective neutral density filters 51a, 51b, and 51c move to the front of the light reflection shade 25, and return to the inside of the storage box 52 from the front of the light reflection shade 25 when inverted. . Further, it is possible to select which neutral density filter is to be moved by an internal clutch or the like (not shown).

Here, a filter that reduces light to about 50% is used as the first neutral density filter 51a.
The second neutral density filter 51b reduces the light by about 25%, and the third neutral density filter 51c reduces the light by about 12.5%. That is, the light transmittance of the first neutral density filter 51a is 50%, the light transmittance of the second neutral density filter 51b is 75%, and
The light transmittance of the neutral density filter 51c is set to 87.5%.

Next, the operation of the second embodiment will be described. All the neutral density filters are stored in the storage box 52,
In a state where no neutral density filter is arranged on the front surface of the light reflection shade 25, the light transmittance becomes 100%, and the plant can be irradiated with strong light as in the midday of summer.
Further, any one of the first neutral density filter 51a, the second neutral density filter 51b, and the third neutral density filter 51c is used.
By sliding the sheet to the front of the light reflection shade 25,
50%, 25%, 12.5% of light can be reduced.

Further, by moving two or three neutral density filters 51a, 51b, 51c to the front of the light reflection shade 25, the amount of light can be reduced in eight steps of 12.5%. Thereby, it is possible to irradiate the plants in the breeding room 13 with light having the optimum intensity according to the breeding stage of the plants.

As in the case of the first embodiment, when light irradiation is started, the dimming rate is gradually reduced by the dimming filter 51 in accordance with the opening of the pores. I have. That is, at the beginning of the irradiation, all the three neutral density filters 51a to 51c are slid to the front of the light reflecting shade 25, and thereafter, the neutral density filters arranged on the front of the light reflecting shade 25 are switched, and the light is gradually reduced. The amount of light is increased.

FIG. 8 shows a third embodiment.
In the second embodiment, the dimming filter is slid, but in the dimming device 60 according to the third embodiment, three dimming screens 61a, 61b, 61 are used.
c is a take-up type, and any of the dimming screens 61 is moved by the screen take-up mechanism 62 to the light reflection shade 2.
The light attenuation rate is adjusted in multiple stages depending on whether the light is sent to the front surface of the light source 5. The light transmittance of the first darkening screen 61a is 50%, the light transmittance of the second darkening screen 61b is 75%, and the light transmittance of the third darkening screen 61c is 87.5%. Are set respectively.

The dimming device 60 according to the third embodiment
Also, the extinction ratio of the light can be set in eight stages according to the combination of the type and the number of the dimming screens sent to the front of the light reflection shade 25. When light irradiation is started, similarly to the second embodiment, the light reflecting shade 25
Is controlled so that the light reaching the plants is gradually increased by switching the dimming screen arranged on the front of the camera.

FIG. 9 shows a fourth embodiment.
The dimming device 70 according to the fourth embodiment includes a circular neutral filter 71 and a filter driving unit 72 that drives the neutral filter 71 to rotate. As shown in FIG. 10, the neutral filter 71 includes six darkening regions 71a having different light transmittances (shades).
To 71f. The first dimming region 71a has a light transmittance of almost 100%. The light transmittance of the second darkening region 71b is approximately 85%, and the sixth darkening region 71f after the second darkening region 71b.
Up to 15% light transmittance.

The filter drive unit 72 drives the neutral filter 71 to rotate, so that any one of the darkening regions 71
The function of moving a to 71f to the front of the light reflection shade 25 is achieved. The light reducing device 70 can reduce the light to a maximum of 75% in increments of 15%, depending on which light reducing region of the neutral filter 71 is arranged in front of the light reflecting shade 25. Thereby, the plant can be irradiated with an appropriate amount of light according to the plant growing stage. In the fourth embodiment as well, when light irradiation is started, similarly to the other embodiments, the dimming region arranged on the front surface of the light reflection shade 25 is the sixth dimming region 7.
By sequentially switching from the 1f side toward the first darkening area 71a, the light reaching the plants is controlled so as to be gradually increased.

FIG. 11 shows a fifth embodiment. The light reduction device 80 according to the fifth embodiment is of a winding type in which the light reduction filter 81 is wound by a filter winding unit 82. As shown in FIG. It has a gradation in which the light transmittance gradually changes toward the other end. The light transmittance can be changed steplessly depending on which part of the neutral density filter 81 is moved to and arranged on the front surface of the light reflection shade 25.

Light reduction device 80 in the fifth embodiment
Also, similarly to the other embodiments, when light irradiation is started, the light transmittance is gradually increased in accordance with the opening of the pores. It should be noted that the neutral filter 71 used in the fourth embodiment may be of a gradation type in which the shading gradually changes like the neutral density filter 81, and the light transmittance may be changed steplessly. Good.

Next, a case in which the amount of light emitted from the microwave lamp 23 is electrically adjusted will be described. Even when the light amount is electrically adjusted, the configuration of the plant growing box 10 is the same as that in FIG.
Is substantially the same as that shown in FIG.
It is not necessary to provide 0 or the like. Although the lamp driving circuit 22 in the first to fifth embodiments applies a constant high DC voltage, the following is used instead.

In the sixth embodiment, as shown in FIG. 13, a lamp drive circuit 100 using a triac is employed. A triac 103 is connected to the primary side circuit of the high voltage transformer 101 included in the lamp driving circuit 100 in series with an AC power supply 102 having a single-phase AC voltage of 200 volts. Also, the trigger terminal 103a of the triac 103
And a trigger circuit 104 for flowing a gate current between the T1 terminal 103b and the T1 terminal 103b.

The full-wave rectifier circuit 105 is connected to the secondary side of the high-voltage transformer 101, and the output of the full-wave rectifier circuit 105 is connected to the cathode 21 a of the magnetron 21.
The anode 21b of the magnetron 21 is grounded. In addition, the heater section of the magnetron 21 is supplied with a heater current from the heater transformer 106.

The trigger circuit 104 controls the ON timing of the triac 103 by a zero volt switch system. In addition, it has a function of performing hollowing out for each cycle, and the ratio of hollowing out can be changed to various types. Here, 10 cycles are a unit cycle, and the number of cycles to be hollowed out in 10 cycles can be changed to an arbitrary number of cycles from 0 to 9.

FIG. 14 shows the relationship between the anode voltage of the magnetron 21 and the current. The magnetron 21
When the anode voltage becomes equal to or lower than the oscillation start voltage 111, no oscillation occurs. Further, with an anode voltage equal to or higher than the oscillation start voltage 111, a slight change in voltage causes a large change in the current value.
For this reason, it is relatively difficult to perform capacity control that changes the peak value of the anode voltage.

On the other hand, when the voltage application is turned on and off, the microwave lamp 23 flickers, but this has almost no effect on the growth of the plant. Therefore, as shown in FIG. 15, by removing the AC cycle by the triac 103 (the cycle indicated by the dotted line 121 is removed), the time ratio in which the voltage is applied per unit time is controlled, and the peak voltage is reduced. Is adjusted, that is, while the oscillating state is ensured, the light emission amount of the microwave lamp 23 is adjusted.

FIG. 16 shows a lamp driving circuit 200 according to the seventh embodiment. Lamp drive circuit 200
Is for adjusting the amount of light by a PWM inverter method. The lamp driving circuit 200 includes a rectifier 203 for rectifying a single-phase AC from an AC power supply 202 and a smoothing circuit 204 including a capacitor for smoothing the rectified waveform.
, A power transistor 205, and a PWM control circuit 206 for performing on / off control of the power transistor 205
And The output voltage of the PWM control circuit 206 is
It is connected to the cathode 21 a of the magnetron 21. The heater transformer 106 and the like are the same as those shown in FIG. 13, and a description thereof will be omitted.

The lamp drive circuit 200 controls the turning on and off of the power transistor 205 by the PWM control circuit 206 to generate a DC high voltage in a rectangular wave shape as shown in FIG.
a. PWM control circuit 206
By controlling the timing of turning on and off the power transistor 205, the pulse widths 211 and 212 and the duty ratio are changed, and the light amount is changed while maintaining the peak voltage 213.

In addition, by superimposing a DC voltage on the bias voltage corresponding to the oscillation start voltage 111, the anode voltage is prevented from dropping below the oscillation start voltage 111, and the DC voltage to be superimposed is increased or decreased. The light emission amount may be adjusted by controlling the light emission amount. Further, by controlling the heater current of a microwave electron tube (such as a magnetron), the amount of light emission can be adjusted.

Also in the case of electrically dimming in this way, as in the first to fifth embodiments, when light irradiation is started, the light is controlled according to the degree of opening of the pores.
The light amount is gradually increased. Further, the final light amount is limited to a value corresponding to the plant growing stage.

In the embodiment described above, the dimming device for reducing the amount of light reaching the plant by the light-blocking wings, the dimming filter, and the like has been described. However, the dimming method is not limited to the above.
For example, the amount of light may be reduced by a mechanism such as an aperture of a camera. In the case of the electric type, the light emission amount may be adjusted by using a thyristor or the like in addition to the triac.

[0063]

According to the plant growing box of the present invention, the amount of light reaching the plant to be grown can be adjusted to an arbitrary value, so that light having an appropriate intensity according to the growing stage is applied to the plant. Can be irradiated. In addition, when light irradiation is started, the amount of light is gradually increased so as to match the degree of opening of the pores, so that it is possible to prevent a situation where leaf tissue is damaged due to suddenly strong light.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a light irradiation device and a dimming device provided in a plant growing box according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a plant growing box according to the first embodiment of the present invention.

FIG. 3 is an explanatory diagram showing a dimming device provided in the plant growing box according to the first embodiment of the present invention.

FIG. 4 is an explanatory diagram showing a state in which light shielding wings of the dimming device of the plant growing box according to the first embodiment of the present invention are opened.

FIG. 5 is an explanatory diagram showing a state in which light shielding wings of the dimming device of the plant growing box according to the first embodiment of the present invention are closed.

FIG. 6 is an explanatory diagram showing a change in the degree of opening of the pores from the start of light irradiation and a change in the intensity of light emitted from the light irradiation device to the plant.

FIG. 7 is an explanatory view showing a light irradiation device and a dimming device of a plant growing box according to a second embodiment of the present invention.

FIG. 8 is an explanatory diagram showing a light irradiation device and a dimming device included in a plant growing box according to a third embodiment of the present invention.

FIG. 9 is an explanatory diagram showing a light irradiation device and a dimming device of a plant growing box according to a fourth embodiment of the present invention.

FIG. 10 is an explanatory diagram showing a circular neutral filter used in a dimming device provided in a plant growing box according to a fourth embodiment of the present invention.

FIG. 11 is an explanatory view showing a light irradiation device and a dimming device of a plant growing box according to a fifth embodiment of the present invention.

FIG. 12 is an explanatory diagram showing a neutral filter used in a dimming device included in a plant growing box according to a fifth embodiment of the present invention.

FIG. 13 is a circuit diagram showing a lamp driving circuit for driving a microwave lamp included in a plant growing box according to a sixth embodiment of the present invention.

FIG. 14 is an explanatory diagram showing anode voltage / current characteristics of a microwave lamp.

FIG. 15 is an explanatory diagram showing output waveforms of a lamp drive circuit included in a plant growing box according to a sixth embodiment of the present invention.

FIG. 16 is a circuit diagram showing a lamp driving circuit for driving a microwave lamp included in a plant growing box according to a seventh embodiment of the present invention.

FIG. 17 is an explanatory diagram showing output waveforms of a lamp drive circuit included in the plant growing box according to the seventh embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Plant growing box 13 ... Growing room 14 ... Machine room 20 ... Light irradiation device 21 ... Magnetron 21a ... Cathode 21b ... Anode 22, 100, 200 ... Lamp drive circuit 23 ... Microwave lamp 24 ... Microwave shielding screen 25 ... Light Reflector shade 26 Cooling unit 30, 50, 60, 70, 80 Light dimmer 31 Light shielding blade 32 Motor 51a-51c, 81 Light dimming filter 53 Filter driving mechanism 61a-61c Dimming screen 62 ... Screen Winding mechanism 71: Neutral filters 71a to 71f ... Light extinction area 72 ... Filter driving unit 82 ... Filter winding unit 101 ... High voltage transformer 102, 202 ... AC power supply 103 ... Triac 104 ... Trigger circuit 105 ... Full wave rectification circuit 106 ... Heater transformer 111: oscillation start voltage 2 3 ... Rectifier 204 ... smoothing circuit 205 ... power transistor 206 ... PWM control circuit

Claims (8)

[Claims] 1. A plant growing box for growing plants by irradiating the plants with artificial light, a microwave lamp for emitting light for irradiating the plants to be grown, and light emitted from the microwave lamps reaching the plants. Dimming means arranged on the optical path up to the light source, wherein the amount of light reaching the plant among the light emitted from the microwave lamp is reduced to an arbitrary value by the dimming means. Plant growing box. 2. The dimming means includes a light-blocking wing rotatable from a state parallel to the light directed to the plant to a state perpendicular to the light, and a motor for rotating the light-blocking wing. ,
The plant growing box according to claim 1, wherein the amount of light reaching the plant among the light emitted from the microwave lamp is reduced to an arbitrary value by changing an angle of the light shielding wing by the motor. . 3. The light-reducing means includes a plurality of light-reducing filters having different light transmittances, and light-reducing filter inserting means for moving and inserting a light-reducing filter into the optical path, and inserting the light-reducing filter into the optical path. The plant growing box according to claim 1, wherein the amount of light to be reduced is changed in multiple stages by selecting the type and the number of the neutral density filters. 4. The neutral density filter according to claim 1, wherein the neutral density filter has a density that changes from a high light transmittance state to a low light transmittance state, and the neutral filter is moved to insert a part of the neutral filter into the optical path. The plant growing box according to claim 1, further comprising a filter moving unit, wherein the amount of light to be reduced is changed by selecting a region to be inserted into the optical path. 5. A plant growing box for irradiating plants with artificial light, comprising: a microwave lamp for emitting light for irradiating the plants to be grown; and a lamp driving circuit for lighting the microwave lamps. The plant growing box, wherein the lamp driving circuit is capable of adjusting the light emission amount of the microwave lamp to an arbitrary value. 6. The microwave lamp according to claim 1, wherein the lamp driving circuit changes a ratio of a time for applying a predetermined high voltage between a cathode and an anode of the microwave electron tube of the microwave lamp in a unit time. The plant cultivation box according to claim 5, wherein the light emission amount is controlled. 7. The lamp driving circuit controls on / off of an alternating current supplied to a primary side of a transformer for generating a high voltage applied between a cathode and an anode of a microwave electron tube of the microwave lamp. 6. The plant growing box according to claim 5, further comprising an AC power adjusting circuit for adjusting the light emission amount of the microwave lamp by increasing / decreasing a ratio of the number of hollowing cycles. 8. The lamp driving circuit includes a PWM inverter circuit for generating a high voltage applied between a cathode and an anode of a microwave electron tube of the microwave lamp, and changes a width of a generated pulse. 6. The plant growing box according to claim 5, wherein the amount of light emitted from said microwave lamp is adjusted.