JPH09115328A - Recessed type ceiling luminaire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lower the height of a ceiling back necessary for ceiling recessing work. SOLUTION: This luminaire is provided with a fixture main body 3 for storing a fluorescent lamp 1 inside to be recessed and mounted on a ceiling 11, a ballast 6 for turning ON the fluorescent lamp 1, and a top plate 4 on which one end side is mounted on the top end of the luminaire main body 3, the other end side is protruded to the transverse direction of the luminaire main body 3, and the ballast 6 is mounted. The top plate 4 is made turning-movable in a direction in a roughly vertical face toward the luminaire main body 2, a turning movement part 4b protruding to the lower direction than the ballast 6 is provided and constituted, and a contact part 4c for supporting the weight of the ballast 6 in contact with the back face of the ceiling 11 by turning movement of the turning movement plate part 4b is formed on the other end side of the turning movement plate 4b. In addition, guide piece 4d which sides the end part of a recessing hole 11a provided on the ceiling 11 and guides the turning movement plate part 4b to the recessing hole 11a is provided on one end side of the contact part 4c of the turning movement plate part 4b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceiling-embedded luminaire, and more particularly to a ceiling-embedded luminaire including a ballast for lighting a fluorescent lamp.

[0002]

2. Description of the Related Art Generally, in a ceiling-embedded luminaire that is embedded and mounted in an embedding hole provided in a ceiling, the height of the entire fixture should be minimized due to restrictions such as the height of the body behind the ceiling. It is desired to lower it. Therefore, it is possible to avoid mounting the components such as the ballast on the upper side of the instrument body in a stacked manner, and in many cases, the instruments are arranged laterally of the instrument body.

FIG. 9 and FIG. 10 show a conventional ceiling-embedded luminaire (first conventional example). In this ceiling-embedded luminaire, a single-base fluorescent lamp 1a, which is a fluorescent lamp 1, is inserted in a substantially cylindrical shape with a downward opening, and is attached to three side surfaces. An instrument body 3 provided with a mounting spring 2a that is a metal fitting 2, and a substantially L-shape, one end of which is attached to an upper end of the instrument body 3 and the other end of which is directed downward so as to project to the side of the instrument body 3. And a frame 7 mounted on the lower surface side of the instrument main body 3, and a ballast 6 housed in a ballast box 5. The socket 8 is attached to the side of the top plate 4 facing downward, which is the other end of the top plate 4, and the ballast box 5 to which the ballast 6 is attached has the terminal block 9 attached thereto. Provided,
The ballast 6, the terminal block 9, and the socket 8 are electrically connected by a lead wire 10.

In the ceiling-embedded luminaire having the above-mentioned structure, the ballast box 5 is first inserted into the embedding hole 11a provided in the ceiling 11 and placed on the back surface of the ceiling 11 in the construction. After that, the three mounting springs 2a are simultaneously deformed toward the side wall of the device body 3 to push the device body 3 into the embedding hole 11a, and the elasticity of the mounting springs 2a fixes the device body 3 to the ceiling 11. . And the instrument body 3
Then, by mounting the frame body 7 from the lower surface side of the ceiling 11, the ceiling 11 is constructed.

FIG. 11 shows another conventional ceiling-embedded luminaire (second conventional example). The difference from the first conventional example is that a fluorescent lamp is installed in the central axis of the main body 3 of the luminaire. And a reflector plate 12 is provided so as to substantially surround the periphery of the top plate 4, and the ballast 6 and the terminals are provided on the lower surface side of the portion of the top plate 4 projecting to the side of the instrument body 3. The mount 9 and the like are attached, and the mounting bracket 2 is replaced with three mounting springs 2a and two mounting claws 2b are provided, and the other configurations are similar to those of the first conventional example.

The mounting claws 2b are on the side wall of the instrument body 3 on the side where the ballast 6 is mounted on the top plate 4, and on the opposite side thereof are two grooves (not shown) vertically elongated. ),
The lower end is located outside the instrument body 3, projects obliquely downward, and is slidable in the vertical direction. Then, by sandwiching the ceiling 11 with the lower end of the instrument body 3 and the tip of the mounting claw 2b that is outside the instrument body 3 and protrudes downward, the instrument body 3 is installed on the ceiling 11. There is.

FIGS. 12 and 13 show another conventional ceiling-embedded luminaire (third conventional example).
The difference from the second conventional example is that the top plate 4 is formed so as to have a substantially L-shaped cross section, and one piece of the top plate 4 is arranged on the side of the instrument body 3 and directed downward. The socket 8 to which the single-base fluorescent lamp 1a, which is the fluorescent lamp 1, is attached to one piece in a substantially horizontal direction is attached to one piece toward the instrument body 3 side, and on the lower surface of the other piece that protrudes to the side of the instrument body 3 The ballast 6 is mounted so that the lengthwise direction of the single-base fluorescent lamp 1a and the lengthwise direction of the ballast 6 are substantially horizontal, and the two mounting claws 2b, which are the mounting brackets 2, are attached to the device body 3 in plan view. The ballast 6 is provided so as to be biased to the side on which the ballast 6 is disposed, and the other configurations are substantially the same as those of the second conventional example.

[0008]

However, in the ceiling-embedded luminaire shown in the first conventional example configured as described above, the ballast box 5 is required to house the ballast 6. In addition, in the case of the embedding construction as well, it is necessary not only to insert the device main body 3 after inserting the ballast box 5 into the embedding hole 11a, but also to provide the mounting springs 2a which are the mounting brackets 2 at three places. Together with this, there was a problem that the number of parts increased and workability was poor.

In the ceiling-embedded luminaire shown in the second conventional example, since the mounting claw 2b is provided on the side wall of the luminaire body 3 on which the stabilizer 6 is arranged, the stabilizer is provided. 6 not only interferes with the mounting work performed by sliding the mounting claw 2b and deteriorates the workability, but the vertical sliding of the mounting claw 2b is restricted by the stabilizer 6, that is, the mounting claw 2b is There is a problem in that the range of sliding in the vertical direction becomes narrower, which may limit the plate thickness of the ceiling 11 to which the device body 3 is attached. Also, the mounting claw 2b
When the ballast 6 is provided at a position other than the portion where the ballast 6 is provided, the ballast 6 is a heavy object and is provided at the upper end of the device body 3 and at a position deviated to one side from the center of the device. There is a problem in that there is a risk that the tool 3 will tilt and a gap will be created between the tool body 3 and the ceiling 11. Further, even though the height of the instrument body 3 can be reduced, the top plate 4 is configured to project laterally at the upper end of the instrument body 3, and therefore, when it is embedded in the ceiling 11 and attached, the tip of the top plate 4 is attached. The trace drawn by is the embedded hole 1
There is a problem that it hits the ceiling structure above 1a, and therefore the height of the embedded device, that is, the height between the back surface of the ceiling 11 and the ceiling structure, which is the height of the ceiling required for the embedding construction, becomes high. there were.

Further, in the ceiling-embedded luminaire shown in the third conventional example, the two mounting claws 2 which are the mounting brackets 2.
Since b is unevenly provided on the side where the stabilizer 6 is disposed in a plan view, there is a problem that it is difficult to insert the instrument body 3 into the embedding hole 11a of the ceiling 11 and the workability is poor. Also,
Since the ballast 6 is provided outside the fixture body 3 so that the longitudinal direction of the single-base fluorescent lamp 1a and the longitudinal direction thereof are substantially parallel to each other, the ballast 6 and the socket 8 of the top plate 4 are attached to each other. A space for accommodating at least the longitudinal direction of the ballast 6 is required between the side walls of the instrument body 3, and the distance between the tip of the top plate 4 and the center of the instrument body 3 becomes long. And the instrument body 3
When it is inserted into the embedding hole 11a of the ceiling 11, it is necessary to insert it from the tip side of the top plate 4 into the embedding hole 11a.
When the distance between the tip of the top plate 4 and the center of the instrument body 3 becomes long, the locus drawn by the tip of the top plate 4 at the time of embedding is embedded in the embedding hole 11.
There is a problem that it hits the ceiling skeleton above a, and therefore the height of the equipment to be embedded, that is, the height between the back surface of the ceiling 11 and the ceiling skeleton, which is the height behind the ceiling required for the embedding construction, becomes high. there were.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a ceiling-embedded luminaire in which the height of the back of the ceiling required for embedding in the ceiling is reduced. To do.

[0012]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides an apparatus main body 3 in which the fluorescent lamp 1 is housed inside and is mounted and embedded in the ceiling 11 in the invention described in claim 1. A ballast 6 for lighting the fluorescent lamp 1; and a top plate 4 having one end attached to the upper end of the instrument body 3 and the other end protruding laterally of the instrument body 3 and having the ballast 6 attached. In the ceiling-embedded luminaire, the ceiling plate 4 has one end that is rotatable in a substantially vertical inward direction with respect to the fixture body 3 and the other end that is lower than the ballast 6. The rotating plate portion 4b is provided so as to protrude to the other side, and the other end side of the rotating plate portion 4b is brought into contact with the back surface of the ceiling 11 by the rotation of the rotating plate portion 4b so that the stabilizer 6 It is characterized in that a contact portion 4c for supporting the weight is formed. That.

According to the second aspect of the present invention, the first aspect is provided.
In the ceiling-embedded lighting fixture described above, the rotating plate portion 4b.
The one end side of the contact portion 4c of the above is slid on the end portion of the embedding hole 11a provided in the ceiling 11 so that the rotating plate portion 4b is embedded in the embedding hole 11.
It is characterized in that a guide piece 4d for guiding to a is provided.

According to a third aspect of the present invention, in the ceiling-embedded luminaire according to the first or second aspect, the abutment portion 4c is rounded so that the ceiling 11 of the ceiling 11 is embedded. It is characterized in that a sliding portion 4e that slides on the back surface is formed.

According to the invention described in claim 4, a single-base fluorescent lamp 1a is housed in the interior thereof in a substantially horizontal direction, and the instrument body 3 is embedded and mounted in the ceiling 11.
A ballast 6 for turning on the single base fluorescent lamp 1a, and a socket 8 for mounting the single base fluorescent lamp 1a while being attached to the instrument body 3 so as to project laterally.
In a ceiling-embedded luminaire having a top plate 4 to which the ballast 6 is attached, the ballast 6 has a longitudinal direction substantially in a horizontal plane and a lamp insertion direction of the socket 8. It is characterized by being attached so as to be substantially vertical.

According to the invention of claim 5, claim 4 is
The above-described ceiling-embedded luminaire is characterized in that a contact portion 4c that comes into contact with the back surface side of the ceiling 11 is provided at the tip of the top plate 4.

[0017]

1 to 4 show a first embodiment of a ceiling-embedded lighting fixture according to the present invention, in which a mounting bracket 2 is mounted. The instrument main body 3 and the top plate 4 to which the ballast 6, the socket 8 and the terminal block 9 are attached are configured.

The instrument body 3 has a substantially cylindrical shape with a downward opening, and a lamp insertion hole 3 into which a single-base fluorescent lamp 1a, which is the fluorescent lamp 1, is inserted in a substantially horizontal direction on the side surface side.
a is provided, and two mounting springs 2a, which are mounting brackets, are mounted on the side wall in the direction substantially orthogonal to the lamp insertion direction. Further, a flange portion 3b formed substantially vertically from the side wall side toward the outside of the opening is formed at the lower opening end, and the side wall of the instrument body 3 above the flange portion 3b has a vertical direction. A plurality of short ribs 3c are formed.

The top plate 4 is a front view of the instrument main body 3,
The fixed plate portion 4a is formed in a substantially L shape, and the fixed plate portion 4a is formed in a substantially U shape when viewed from the same direction.
And a rotating plate portion 4b that is rotatably engaged with. One end side of the substantially L-shaped fixing plate portion 4a is the instrument body 3
Is formed by a horizontal piece 4f fixed to the upper end of the lamp, and the other end of the hanging piece 4g is directed downward. The hanging piece 4g is arranged so as to face the lamp insertion hole 3a of the appliance body 3 and the hanging piece 4g. The socket 8 is attached to the lamp body 3 toward the lamp insertion hole 3a side.
A slit-shaped engagement hole 4h is provided near the upper end of the hanging piece 4g.

Further, in the rotating plate portion 4b, one end, which is the side of the upper end piece 4k located on the upper side, which is opened in a substantially U-shape, is inserted into the engaging hole 4h of the fixed plate portion 4a and the tip thereof is bent. A ballast 6 is attached to the upper end piece 4k inside the substantially U-shape, and a terminal block 9 is attached to the outer side of the vertical piece 4m that is substantially perpendicular to the upper end piece 4k. There is. Further, the lower end of the vertical piece 4m is bent toward the side wall side of the instrument body 3 and further bent toward the upper end piece 4k to have a substantially V-shaped cross section. The bent portion at the lowermost end serves as a contact portion 4c that supports the weight of the ballast 6 by contacting the back surface of the ceiling 11 by the rotation of the rotation plate portion 4b, and the outer surface of the contact portion 4c is It is a sliding portion 4e that is rounded and slides on the back surface of the ceiling 11. The space between the abutting portion 4c and the vertical piece 4m to which the terminal block 9 is attached is the embedding hole 11a provided in the ceiling 11.
Is a guide piece 4d that slides on the end of the guide plate to guide the rotating plate portion 4b into the embedding hole 11a.

When the ceiling-embedded luminaire constructed as described above is installed on the ceiling 11, as shown in FIG. 2, first, the rotating plate portion 4b of the top plate 4 is rotated downward. The other end side of the instrument body 3 substantially in contact with the side wall of the instrument body 3
Aligning b with the embedding hole 11a of the ceiling 11, the rotating plate portion 4b
The guide piece 4d is brought into contact with the end portion of the embedding hole 11a and slid and pushed in, and then the instrument body 3 is moved so that the contact portion 4c slides on the back surface side of the ceiling 11, Mounting bracket 2
It is constructed by pressing the mounting spring 2a, which is the above, to the device body 3 side to insert the device body 3 into the embedding hole 11a, and holding the device body 3 on the ceiling 11 by the elasticity of the mounting spring 2a.

Because of this structure, in the ceiling-embedded lighting fixture according to the present embodiment, the ceiling 11
At the time of embedding in the floor, the rotating plate 4 which is the tip side of the top plate 4
b rotates downward around the instrument body 3 side, so that the rotating plate portion 4b is positioned below the extension line of the fixed plate portion 4a. Therefore, the rotating plate portion 4 which is the tip of the top plate 4
The height of the locus of the tip of b drawn at the time of embedding from the back surface of the ceiling 11 becomes low, and in some cases, the inside (lower side) of the locus drawn by the corners of the horizontal piece 4f and the hanging piece 4g of the fixed plate portion 4a. As a result, the height of the ceiling above which the lighting fixture is embedded can be lowered. Further, due to the rotation of the rotating plate portion 4b, the lower contact portion 4c of the rotating plate portion 4b abuts against the back surface side of the ceiling 11 to support the weight of the ballast 6 regardless of the plate thickness of the ceiling 11. It is possible to prevent the instrument body 3 from being tilted. Further, during the embedding work, the guide piece 4d serves as a guide to the embedding hole 11a at the time of the embedding work, and the rotating plate portion 4b to which the stabilizer 6 is attached can be easily inserted. Since the contact portion 4c contacts the back surface of the ceiling 11 and supports the weight of the ballast 6, the construction can be facilitated. Furthermore, the contact portion 4
Since c supports the weight of the ballast 6, the mounting bracket 2 of the instrument main body 3 has a weak holding force, that is, the mounting bracket 2 is easily elastically deformed for construction, and the workability is further improved.
In addition, since the contact portion 4c is bent to have a smooth rounded surface, the contact portion 4c slides smoothly without being caught on the back surface of the ceiling 11, and the workability is further improved.

3 and 4 show modifications of the top plate 4 of the ceiling-embedded luminaire according to the present embodiment.
The difference from the top plate 4 shown in FIG. 1 and FIG. 2 is that a substantially C-shaped engaging claw 4n is provided on one end side of a rotating plate portion 4b constituting the top plate 4, and the engaging claw 4n is used as a fixing plate. Engagement hole 4h provided in the portion 4a
It is the point that the rotating plate portion 4b is rotatably engaged by inserting the engaging pin 4p into the above, and the structure is the same as that of the above-mentioned ceiling-embedded lighting fixture. Produce an effect.

5 to 7 show a second embodiment of the ceiling-embedded lighting apparatus according to the present invention. The difference from the first embodiment is the top plate 4, Others are the first
The configuration is substantially the same as that of the embodiment.

The top plate 4 is composed of only the fixed plate portion 4a,
The horizontal piece 4f is substantially L-shaped in a plan view, and the hanging piece 4g is formed substantially vertically from the widened portion on the tip side thereof. Further, one end side of the horizontal piece 4f is fixed to the upper end of the instrument body 3, and the hanging piece 4g is arranged downward so as to face the lamp insertion hole 3a of the instrument body 3. Then, a socket 8 to which the single-base lamp 1a is mounted is attached to the hanging piece 4g toward the lamp insertion hole 3a side of the instrument body 3, and further, the hanging piece 4g.
Side of socket 8 (or horizontal piece 4f above it)
A ballast 6 is attached to the lamp so that its longitudinal direction is perpendicular to the direction in which the single-base lamp 1a is inserted into the socket 8.

With this structure, in the ceiling-embedded lighting fixture according to the present embodiment, the length of the ballast 6 is extended between the outer wall of the fixture body 3 and the hanging piece 4g of the top plate 4. If a height dimension shorter than the dimension is secured, the ballast 6 can be attached. Therefore, the distance between the center of the instrument body 3 and the end of the top plate 4 becomes short, and the tip of the top plate 4 at the time of embedding work. The height from the back of the ceiling 11 of the locus drawn by
The height above the ceiling required for embedding can be reduced.

FIG. 8 shows a third embodiment of the ceiling-embedded luminaire of the present invention. The difference from the second embodiment is that the top plate 4 has a substantially L-shape. The corners that are formed, that is, the points where the chamfered portions 4s are formed at the corners of the horizontal piece 4f and the hanging piece 4g of the top plate 4, and the hanging piece 4g of the top plate 4 project below the stabilizer 6 and the tip is elastic With the point that a supporting piece 4t having a contact portion 4c that abuts on the back surface side of the ceiling 11 is formed, the other structure is substantially the same as that of the second embodiment.

Even with this structure, the same effects as those of the second embodiment can be obtained, and the weight of the ballast 6 causes the contact portion 4c to contact the back surface of the ceiling 11 so that the support piece 4t is supported. There is less risk that the instrument body 3 will be tilted due to being supported, and since the chamfered portion 4s is provided at the corner between the horizontal piece 4f and the hanging piece 4g of the top plate 4, the ceiling during installation is reduced. The height of the locus drawn by the tip of the plate 4 from the back surface of the ceiling 11 is lowered, and the height of the back ceiling required for the embedding work can be further reduced.

In the first embodiment,
Although the top plate 4 formed by the fixed plate portion 4a and the rotating plate portion 4b is illustrated, the present invention is not limited to this, and the top plate is formed only by the rotating plate portion, and the rotating plate portion One end may be rotatably locked near the upper end of the instrument body. In addition, in each of the above-described first and second embodiments, an instrument in which the fluorescent lamp 1 is arranged in the horizontal direction is illustrated, but the present invention is not limited to this. It may be provided in any direction such as a downward direction.

[0030]

As described above, according to the invention as set forth in claim 1, the rotary plate portion, which is the front end side of the top plate, is a tool when it is embedded in the ceiling. The main body side is rotated downward, and the rotary plate portion is positioned below the extension line of the upper surface of the instrument main body. For this reason,
The tip of the rotating plate portion, which is the top end of the top plate, has a locus drawn from the back surface of the ceiling at the time of the embedding work, and the height of the ceiling space required for the embedding work can be lowered. Also, regardless of the thickness of the ceiling, the lower part of the rotating plate comes into contact with the back side of the ceiling to support the weight of the ballast and prevent the tilting of the instrument body. It can prevent the occurrence. Furthermore, since the contact portion contacts the back surface of the ceiling to support the weight of the ballast during the insertion operation of the instrument body, the construction can be facilitated. Also,
Since the abutment portion supports the weight of the ballast, the attachment fitting of the instrument main body has a weak holding force, that is, the attachment fitting is easily elastically deformed for construction, and the workability is further improved.

According to the invention of claim 2, in addition to the effect of the invention of claim 1, the guide piece serves as a guide to the embedding hole at the time of embedding and attaches the ballast. The rotating plate portion is easy to insert, and the workability is further improved.

In addition to the effect of the invention of claim 1 or claim 2, the contact portion is bent and the outer surface is a smooth rounded surface. Therefore, it can slide smoothly without being caught on the back surface of the ceiling, further improving the workability.

Further, in the invention according to claim 4, the ballast is secured between the outer wall of the instrument body and the hanging piece of the top plate by ensuring a height dimension shorter than the longitudinal dimension of the ballast. Therefore, the distance between the center of the instrument body and the end of the top plate is shortened, and the tip of the rotating plate that is the top of the top plate is drawn from the back surface of the ceiling of the trajectory drawn during embedding work. Since the height is low, the height above the ceiling required for embedding can be reduced.

According to the invention of claim 5, in addition to the effect of the invention of claim 4, the weight of the ballast is supported by the abutting portion, and the risk that the instrument body tilts is reduced.

[Brief description of the drawings]

FIG. 1 is a front view showing a main part of a ceiling-embedded lighting fixture according to a first embodiment of the present invention in a ceiling-mounted state.

[Fig. 2] Fig. 2 shows the same construction procedure as above, (a) is a front view showing a state where the guide piece slides along the end of the embedding hole, and (b) shows the guide piece where the guide piece is on the ceiling back surface side of the embedding hole. Front view showing that the contact body slides under the ceiling and the fixture body is inserted into the embedding hole. (D) shows the ceiling mounted state. It is a figure.

FIG. 3 is a perspective view showing a modified example of the top plate of the above.

FIG. 4 is an exploded perspective view of the same.

FIG. 5 is a perspective view of a ceiling-embedded lighting fixture according to a second embodiment of the present invention.

FIG. 6 is a perspective view of the main part of the same as seen from a different direction.

FIG. 7 is a plan view of the same.

FIG. 8 is a front view showing a ceiling-mounted state of the ceiling-embedded lighting fixture according to the third embodiment of the present invention.

FIG. 9 is a front view of essential parts showing a ceiling-mounted state of a conventional ceiling-embedded lighting fixture (first conventional example).

FIG. 10 is a plan view of the same.

FIG. 11 is a front view of a main part showing a state where another conventional ceiling-embedded lighting fixture (second conventional example) is mounted on the ceiling.

FIG. 12 is another conventional ceiling-embedded luminaire (third embodiment).
FIG. 7 is a plan view of a conventional example of FIG.

FIG. 13 is a front view of the same.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fluorescent lamp 1a Single-sided fluorescent lamp 3 Instrument body 4 Top plate 4a Fixed plate part 4b Rotating plate part 4c Contact part 4d Guide part 4e Sliding part 6 Ballast 8 Socket 11 Ceiling 11a Embedded hole

Claims (5)

[Claims] 1. A fixture main body which houses a fluorescent lamp therein and is embedded in the ceiling, a ballast for lighting the fluorescent lamp, one end side of which is attached to the fixture main body and the other end of which is lateral to the fixture main body. In a ceiling-embedded luminaire having a top plate to which the stabilizer is attached and which protrudes, the top plate is configured such that one end side thereof is rotatable in a substantially vertical inward direction with respect to the fixture body. And the other end side is provided with a rotating plate portion projecting below the stabilizer, and the other end side of the rotating plate portion contacts the back surface of the ceiling by the rotation of the rotating plate portion. A ceiling-embedded lighting fixture is characterized in that an abutting portion for supporting the weight of the ballast is formed. 2. A guide piece for sliding the end portion of an embedding hole provided on the ceiling to guide the rotating plate portion to the embedding hole, on one end side of the contact portion of the rotating plate portion. The ceiling-embedded luminaire according to claim 1, which is provided. 3. The ceiling embedding device according to claim 1 or 2, wherein the abutting portion is rounded to form a sliding portion that slides on the back surface of the ceiling during embedding. Type lighting fixtures. 4. A fixture main body in which a single base fluorescent lamp is housed in a substantially horizontal direction and is embedded and mounted in a ceiling, a ballast for lighting the single base fluorescent lamp, and a lateral side of the fixture main body. In the ceiling-embedded luminaire, which is mounted so as to project into the ceiling, and has a top plate to which the socket for mounting the single-base fluorescent lamp and the ballast are mounted, the ballast has a longitudinal direction. Is mounted in a substantially horizontal plane direction so as to be substantially perpendicular to the lamp insertion direction of the socket. 5. The ceiling-embedded luminaire according to claim 4, wherein the top plate is provided with an abutting portion that abuts against a back side of the ceiling.