LED bulb

Abstract

To provide an LED bulb with which it is possible to obtain the stimulus of a gamma wave easily in a daily life.SOLUTION: Provided is an LED bulb 10 which is used for an AC power supply of a commercial frequency 50 Hz or 60 Hz, wherein a power supply connector 2 is supplied with power from a bulb socket. An LED element 77 is mounted on an LED substrate 7. A control circuit for controlling light emission of the LED element 77 is mounted on a main substrate 4. The LED substrate 7 is accommodated in an LED cover 8, and the light of the LED element 77 passes through a spherical lighting unit 88. A housing 3 is composed of a bel-shaped upper housing 31 with the power supply connector 2 connected to the top of it and a cylindrical lower housing 32 in combination, with the main substrate 4 accommodated in the inside. A 26 Hz to 44 Hz frequency in the frequency band of a gamma wave is defined as a specific frequency. A control circuit causes the LED element 77 to emit light by a drive signal in which a signal of the specific frequency is superimposed on the alternating current of a commercial frequency.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an LED light bulb. [Background technology]

[0002] Devices that emit 40 Hz sound or light have been known based on research reports that stimulating the brain with gamma waves of about 40 Hz is effective in improving dementia.

[0003] For example, Patent Document 1 discloses a technology for a gamma wave sound signal processing device, and Patent Document 2 discloses a phototherapy system equipped with a strobe blue light source that operates at gamma wave frequencies. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 7307929 [Patent Document 2] Japanese Patent Publication No. 2020-507414 Summary of the Invention [Problem to be solved by the invention]

[0005] The prior art described in Patent Document 2 generates gamma wave light for medical purposes, such as the treatment and prevention of dementia. This type of phototherapy device requires users to continuously view the flashing light for, for example, about an hour per day to achieve the desired medical effect. However, 40 Hz light flickers, making continuous viewing uncomfortable. Furthermore, it would be a burden for healthy individuals, not intended for serious medical purposes, to spend time simply viewing the flashing light. Therefore, this device is not suitable as a device for easily obtaining gamma wave stimulation in everyday life.

[0006] Furthermore, although Patent Document 2 describes that the phototherapy device includes a lighting fixture equipped with an LED-based light source (for example, a lamp), it does not disclose any specific configuration of the lighting fixture.

[0007] The present invention was created in light of these circumstances, and its purpose is to provide an LED light bulb that allows gamma wave stimulation to be easily obtained in everyday life. [Means for solving the problem]

[0008] The present invention is an LED light bulb used with an AC power supply having a commercial frequency of 50 Hz or 60 Hz, and comprises a power connector (2), an LED board (7), a main board (4), an LED cover (8), and a housing (3).

[0009] The power connector receives power from the light bulb socket. The LED board has an LED element (77) mounted on it. The main board has a control circuit mounted on it that controls the light emission of the LED element. The LED cover houses the LED board, and the light from the LED element is transmitted through a spherical lighting section (88). The housing is a combination of a bell-shaped upper housing (31) with the power connector connected to its top and a cylindrical lower housing (32), and houses the main board inside.

[0010] The specific frequency is defined as a frequency between 26Hz and 44Hz within the gamma wave frequency band. The control circuit causes the LED element to emit light using a drive signal that is a commercial frequency AC current superimposed with a specific frequency signal.

[0011] The LED light bulb of the present invention contains gamma waves in a specific frequency signal superimposed on a commercial frequency AC, so flickering is suppressed to a level that is not noticeable to the average person compared to when only gamma waves are used for lighting. Therefore, by using it as a lighting fixture in the living room, bathroom, kitchen, etc., users can easily enjoy the stimulation of gamma waves in their daily lives.

[0012] Preferably, the LED bulb of the present invention further comprises a heat sink (5) made of aluminum alloy, disposed between the housing and the LED substrate, and having a plurality of heat dissipation fins (55). An insulating thermally conductive bond (6) is applied between the heat sink and the LED substrate to transfer heat from the LED substrate, which is generated by the application of current to the LED elements, to the heat sink.

[0013] This reduces heat generation in the LED substrate even during long periods of continuous use, improving reliability.

[0014] However, there is a problem in that the space required for mounting the control circuit on the main board is large, resulting in an axial length longer than that of a typical LED light bulb. Therefore, more preferably, the main board is formed in a shape that follows the axial cross-sectional shape of the internal space of the housing, and is housed in the housing with the board surface oriented parallel to the axis of the housing.

[0015] This allows the axial length of the LED bulb to be made compact, which reduces restrictions on installation in lighting fixtures and improves versatility. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is an external view of an LED light bulb according to an embodiment. [Figure 2] An exploded perspective view of the LED bulb in Figure 1. [Figure 3] Figure 1 shows an axial cross section of the LED bulb. [Figure 4] FIG. 2 is a cross-sectional perspective view of the LED bulb in FIG. 1. [Figure 5] FIG. 2 is a diagram showing the wiring pattern layout of the main board. DETAILED DESCRIPTION OF THE INVENTION

[0017] (One embodiment) An LED bulb according to one embodiment of the present invention will be described with reference to the drawings. This LED bulb is used with an AC power supply with a commercial frequency of 50 Hz or 60 Hz. As shown in FIGS. 1 to 4, an LED bulb 10 according to one embodiment includes a power connector 2, a housing 3, a main board 4, a heat sink 5, an LED board 7, and an LED cover 8. The housing 3 is composed of a bell-shaped upper housing 31 and a cylindrical lower housing 32. Although it is not a tangible component, the gel-like insulating and thermally conductive bond 6 applied between the heat sink 5 and the LED board 7 is shown schematically in the spatial shape of the applied portion.

[0018] The power connector 2 is sized to fit into an E26 bulb socket. The outer surface of the power connector 2 is actually spirally shaped, but the inclination of the spiral is omitted for clarity. The power connector 2 is connected to the top of the upper housing 31, and receives power from the bulb socket.

[0019] The upper housing 31 and the lower housing 32 are combined together, for example, by an engagement structure of a claw and a recess. A main board 4 is housed inside the housing 3, which is made up of the combined upper housing 31 and lower housing 32. A control circuit that controls the light emission of the LED elements is mounted on the main board 4. This control circuit causes the LED elements to emit light using a drive signal that is a commercial frequency AC current superimposed with a signal of a specific frequency. The specific frequency will be described later.

[0020] Figure 5 shows the wiring pattern layout of the main board 4. Although a detailed explanation is omitted, the main board 4 is mounted with elements such as the inductor L, electrolytic capacitor EC, Zener diode ZD, and resistor R that make up the control circuit, as well as an IC chip U. The wiring pattern is formed in multiple layers. Compared to a typical LED bulb, the control circuit has special functions, so there are more types and numbers of elements, and more space is required to mount the control circuit. When controlling the LED, the IC chip U, indicated by the two-dot chain oval, generates heat.

[0021] The main board 4 is not a simple rectangle, but rather resembles an isosceles trapezoid. The top and bottom edges are parallel straight lines perpendicular to the axial direction, with the top edge being shorter than the bottom edge. The left and right edges consist of an inclined curved portion facing the inner wall of the upper housing 31 and a straight portion perpendicular to the bottom edge facing the inner wall of the lower housing 32. The portion facing the inner wall of the upper housing 31 curves slightly inward, sloping inward from bottom to top, and reaching both ends of the top edge.

[0022] In this way, the main board 4 is formed in a shape that follows the axial cross-sectional shape of the internal space of the housing 3, and is housed in the housing 3 with the board surface oriented parallel to the axis of the housing 3. This allows the axial length of the LED bulb 10 to be compact, even though the space required to mount the control circuit on the main board 4 is larger than in a typical LED bulb.

[0023] The heat sink 5 is made of an aluminum alloy (e.g., A6063) and is formed in a generally cylindrical shape, and has the function of absorbing and dissipating heat. The heat sink 5 is provided between the housing 3 and the LED substrate 7, and has a plurality of heat dissipation fins 55 extending radially outward from the cylindrical portion 53. In one embodiment, the heat dissipation fins 55 are arranged in multiple stages in the axial direction to form a circumferential heat dissipation groove, ensuring a large surface area in contact with the outside air.

[0024] A recess 56 recessed one step further than the outer edge is formed on the end face of the heat sink 5 facing the LED substrate 7. The insulating and thermally conductive bond 6 is a gel-like substance with insulating properties and high thermal conductivity, and is applied to the surface of the LED substrate 7 facing the heat sink 5. The LED substrate 7 has multiple LED element 77 chips mounted thereon.

[0025] 2, the lower housing 32, the heat sink 5, and the LED board 7 have assembly holes provided at corresponding positions and are assembled together. The LED board 7 is fixed so as to be in close contact with the bottom surface of the recess 56 of the heat sink 5 via an insulating and thermally conductive bond 6. Wiring (not shown) connecting the main board 4 and the LED board 7 is inserted through the inside of the cylindrical portion 53 of the heat sink 5.

[0026] The LED elements 77 mounted on the LED substrate 7 emit light and generate heat when current is applied. The insulating and thermally conductive bond 6 maintains an insulating distance between the LED substrate 7 and the heat sink 5, and transfers the heat generated by the LED substrate 7 when current is applied to the LED elements 77 to the heat sink 5. As shown by the block arrows in Figure 3, the heat transferred from the LED substrate 7 to the heat sink 5 via the insulating and thermally conductive bond 6 is released into the air from the heat dissipation fins 55 of the heat sink 5.

[0027] The LED cover 8 is formed in a substantially hemispherical cup shape. An opening edge 86 of the LED cover 8 fits into the inner periphery of the recess 56 of the heat sink 5. The LED substrate 7 is housed within the opening of the LED cover 8. When the LED element 77 is energized, light from the LED element 77 is transmitted through the spherical illumination portion 88.

[0028] In one embodiment, the LED light bulb 10 produces light with a brightness of 800 lumens or more, and the light color can be changed to daylight, neutral white, or warm white. The Ra value, a unit of color rendering that indicates the degree to which the color of natural light is reproduced, is 90 or more. The light distribution angle is wide, making it suitable for lighting living rooms, toilets, kitchens, etc.

[0029] In the LED light bulb 10 configured as described above, the control circuit on the main board 4 causes the LED elements 77 on the LED board 7 to emit light using a drive signal in which a signal of a specific frequency is superimposed on AC current with a commercial frequency of 50 Hz or 60 Hz. The term "specific frequency" is defined as a frequency between 26 Hz and 44 Hz within the gamma wave frequency band.

[0030] According to Wikipedia (registered trademark), "Gamma waves are thought to occur when a group of nerve cells emits electrical signals at a frequency of approximately 40 times per second (40 Hz), but are usually thought to range from around 26 Hz to 70 Hz." Based on this, the lower limit of the specific frequency is set to 26 Hz. Furthermore, to avoid overlap with the target commercial frequencies of 50 Hz or 60 Hz, the frequency band of 50 Hz ±10% or more (from 45 Hz) is excluded, and the upper limit of the specific frequency is set to 44 Hz.

[0031] However, in consideration of stimulating gamma waves in the brain, the actual target frequency is 40 Hz, and therefore, it is preferable that the practical specific frequency be set within a frequency range centered around 40 Hz and including a predetermined error (e.g., 40±4 Hz, 40±2 Hz, 40±1 Hz, etc.).

[0032] The control circuit adjusts the brightness of the LED element 77 by adjusting the pulse width of the PWM control. The control circuit also generates a 40 Hz ripple voltage and superimposes it on the PWM signal for LED control. By appropriately adjusting the duty ratio of the PWM signal from the control IC, the peak of the 40 Hz ripple voltage is suppressed to an allowable value or less. As a result, flickering of the LED element 77 is suppressed to the point where it is no longer noticeable to the naked eye.

[0033] Conventional phototherapy devices for medical use require users to continuously view 40 Hz flashing light, making them unsuitable as lighting fixtures for everyday use by the average healthy person. In contrast, the LED light bulb 10 of one embodiment contains gamma waves in a specific frequency signal superimposed on commercial AC, reducing flickering to a level that is unnoticeable to the average person. Therefore, by using the device as a lighting fixture in living rooms, bathrooms, kitchens, etc., users can easily experience gamma wave stimulation in their daily lives.

[0034] In addition, in one embodiment of the LED light bulb 10, heat generated in the LED substrate 7 by energizing the LED elements 77 is transferred to the heat sink 5 via the insulating and thermally conductive bond 6, and is then dissipated into the air from the heat sink 5. This makes it possible to suppress heat generation in the LED substrate 7 even during long periods of continuous use, improving reliability.

[0035] Furthermore, the axial length of the LED bulb 10 can be made compact by devising the shape of the main board 4 on which the control circuit is mounted and the placement of the bulb in the housing 3. This reduces the constraints on installation in lighting fixtures and improves versatility.

[0036] (Other embodiments) (a) In the above embodiment, one main board 4 is accommodated in the housing 3, but in other embodiments, two or more main boards on which the control circuit is separately mounted may be accommodated in the housing.

[0037] (b) In the above embodiment, the heat sink 5 has multiple rows of heat dissipation fins 55 arranged axially to form a circumferential heat dissipation groove, but in other embodiments, multiple rows of heat dissipation fins may be arranged circumferentially to form an axial groove.

[0038] (c) As a means for transferring heat from the LED substrate 7 to the heat sink 5, an insulating plate-shaped or thin-film shaped tangible member such as rubber may be used if it can achieve the same heat dissipation effect as the insulating heat-conducting bond 6.

[0039] As described above, the present invention is not limited to the above-described embodiment, and can be implemented in various forms without departing from the spirit of the present invention. [Explanation of symbols]

[0040] 10 LED bulbs, 2···power connector, 3. Housing, 31···Upper housing, 32···Lower housing, 4. Main board, 5. Heat sink, 55. Heat dissipation fin, 6. Insulating heat conductive bond, 7 LED substrate, 77 LED element, 8···LED cover, 88···lighting part.

Claims

1. An LED light bulb used with an AC power source having a commercial frequency of 50 Hz or 60 Hz, a power connector (2) to which power is supplied from a light bulb socket; an LED substrate (7) on which an LED element (77) is mounted; a main board (4) on which a control circuit for controlling the light emission of the LED element is mounted; an LED cover (8) that houses the LED substrate and transmits light from the LED element through a spherical illumination portion (88); a housing (3) which is a combination of a bell-shaped upper housing (31) having the power connector connected to its top and a cylindrical lower housing (32), and which houses the main board inside; Equipped with If we define the frequency range of gamma waves between 26 Hz and 44 Hz as a specific frequency, The control circuit is an LED bulb that causes the LED element to emit light using a drive signal obtained by superimposing a signal of the specific frequency on an AC power supply frequency.

2. The LED display further includes a heat sink (5) made of an aluminum alloy, disposed between the housing and the LED substrate, and having a plurality of heat dissipation fins (55); 2. The LED light bulb according to claim 1, wherein an insulating thermally conductive bond (6) is applied between the heat sink and the LED substrate to transfer heat from the LED substrate generated by energizing the LED element to the heat sink.

3. 3. The LED bulb according to claim 1, wherein the main board is formed in a shape that conforms to the axial cross-sectional shape of the internal space of the housing, and is housed in the housing with the board surface oriented parallel to the axis of the housing.

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