Tube lamp

Abstract

To enable the installation of light source substrates of different widths in a straight-tube lamp. [Solution] The straight tube lamp (100) comprises a cylindrical member (110) extending in the longitudinal direction, a light source substrate (120) on which a light source (122) is arranged, and a substrate holding member (130) arranged inside the cylindrical member (110) and holding the light source substrate (120). The substrate holding member (130) has a stepped portion (130s) connected to a mounting surface on which the light source substrate (120) is attached.

Description

Technical Field

[0001] The present disclosure relates to straight tubes lamps.

Background Art

[0002] As a lamp for lighting, instead of the conventional mercury discharge tube straight tube fluorescent lamp, a straight tube LED lamp in which light emitting diodes (LEDs) are arranged in the longitudinal direction is used. For example, the straight tube LED lamp is used to illuminate an advertising panel by being housed in a sign frame body. The straight tube LED lamp can extend its service life semi-permanently and solve the problem of the service life of the conventional straight tube fluorescent lamp. In addition, since the tubular LED lamp can be directly installed on the frame for the already installed straight tube fluorescent lamp, the convenience as a lighting lamp can be dramatically improved.

[0003] Typically, the straight tube LED lamp is used by being mounted on an LED lamp holding member of a lighting fixture (see Patent Document 1). In the lighting fixture described in Patent Document 1, a straight tube LED lamp having an LED substrate in which LEDs are arranged in a row in the longitudinal direction is fixed and attached to a substrate holding member and a lid member. The lighting fixture of Patent Document 1 is provided with an LED lamp holding member that locks the fitting member of the straight tube LED lamp to suppress the attachment and detachment of the fitting member, thereby improving the holding force of the straight tube LED lamp.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the lighting fixture described in Patent Document 1, the substrate holding member is configured to accommodate an LED substrate in which LEDs are arranged in a single row. On the other hand, if multiple rows of LEDs are to be arranged on the LED substrate in order to provide brighter illumination, it becomes necessary to ensure a wider LED substrate, thus requiring the creation of a different substrate holding member that can appropriately accommodate a wider LED substrate. In this case, it becomes necessary to manufacture a substrate holding member according to the width of the light source substrate, which increases the number of parts.

[0006] This disclosure has been made in view of the above-mentioned problems, and its purpose is to provide a straight tube lamp that can mount light source substrates of different widths using the same substrate holding member. [Means for solving the problem]

[0007] The straight tube lamp according to this disclosure comprises a cylindrical member extending in the longitudinal direction, a light source substrate on which a light source is arranged, and a substrate holding member disposed within the cylindrical member and holding the light source substrate, wherein the substrate holding member has a stepped portion connected to a mounting surface on which the light source substrate is attached. [Effects of the Invention]

[0008] According to this disclosure, it is possible to provide a straight tube lamp that can accommodate light source substrates of different widths using the same substrate holding member. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic perspective view of a straight tube lamp according to the first embodiment. [Figure 2] This is a schematic partially exploded perspective view of a straight tube lamp according to the first embodiment. [Figure 3A] This is a schematic cross-sectional view of a straight tube lamp according to the first embodiment. [Figure 3B] This is a schematic cross-sectional view of the cylindrical member in the straight-tube lamp of the first embodiment. [Figure 4A] This is a schematic cross-sectional view of the substrate holding member in a straight tube lamp according to the first embodiment. [Figure 4B]This is a schematic cross-sectional view of the light source substrate and substrate holding member in a straight tube lamp according to the first embodiment. [Figure 5A] This is a schematic cross-sectional view of a straight tube lamp with different light source substrates attached, according to the first embodiment. [Figure 5B] Figure 5A is a schematic cross-sectional view of the light source substrate and substrate holding member in a straight-tube lamp. [Figure 6] This is a schematic cross-sectional view of a straight tube lamp according to the second embodiment. [Figure 7A] This is a schematic cross-sectional view of the substrate holding member in a straight tube lamp according to the second embodiment. [Figure 7B] This is a schematic cross-sectional view of the light source substrate and substrate holding member in a straight tube lamp according to the second embodiment. [Figure 8A] This is a schematic cross-sectional view of a straight tube lamp with different light source substrates attached, according to the second embodiment. [Figure 8B] Figure 8A is a schematic cross-sectional view of the light source substrate and substrate holding member in a straight tube lamp. [Figure 9A] This is a schematic cross-sectional view of a straight tube lamp according to the third embodiment. [Figure 9B] This is a schematic cross-sectional view of the substrate holding member in a straight tube lamp according to the third embodiment. [Figure 9C] This is a schematic cross-sectional view of the light source substrate and substrate holding member in a straight tube lamp according to the third embodiment. [Figure 10] This is a schematic cross-sectional view of a straight tube lamp with different light source substrates attached, according to the third embodiment. [Modes for carrying out the invention]

[0010] Hereinafter, a straight-tube lamp according to an embodiment of this disclosure will be described with reference to the drawings. In the drawings, the same or corresponding parts will be denoted by the same reference numerals and will not be repeated in the description.

[0011] In the following description, in the X-axis direction of the coordinates shown in the drawings, the left-right direction (the direction that is positive on the X-axis when viewed from the origin of the coordinate axes is the right direction), the Y-axis direction is the front-back direction (the direction that is positive on the Y-axis when viewed from the origin is the back direction), and the Z-axis direction (the direction perpendicular to the XY plane) may be referred to as the up-down direction (the direction that is positive on the Z-axis when viewed from the origin is the up direction).

[0012] [First Embodiment] First, referring to FIG. 1, the straight tube lamp 100 of the present embodiment will be described. FIG. 1 is a schematic perspective view of the straight tube lamp 100 of the present embodiment.

[0013] As shown in FIG. 1, the straight tube lamp 100 extends in the longitudinal direction L. Here, the longitudinal direction L extends in the Y direction. The straight tube lamp 100 irradiates light. For example, the straight tube lamp 100 is mounted on a lighting fixture not shown.

[0014] The straight tube lamp 100 includes a cylindrical member 110 and a mounting portion 140. The cylindrical member 110 is cylindrical and extends in the longitudinal direction L.

[0015] A light source is disposed inside the cylindrical member 110. The cylindrical member 110 transmits the light emitted from the internal light source to the outside. The cylindrical member 110 has translucency. The cylindrical member 110 may be transparent or translucent.

[0016] The mounting portion 140 is attached to an end of the cylindrical member 110 that extends in the longitudinal direction L. The mounting portion 140 serves as a supply port for supplying power from an external power source to the light source disposed inside the cylindrical member 110.

[0017] The straight tube lamp 100 is suitably used as a component of a lighting device. For example, the straight tube lamp 100 is suitably used as a component of a lighting device mounted on a signboard and a showcase.

[0018] Next, referring to FIGS. 1 and 2, the straight tube lamp 100 of the present embodiment will be described. FIG. 2 is a schematic partial exploded perspective view of the straight tube lamp 100 of the present embodiment.

[0019] As shown in Figure 2, the straight tube lamp 100 includes a cylindrical member 110 and a mounting portion 140, as well as a light source substrate 120 and a substrate holding member 130. The light source substrate 120 and the substrate holding member 130 are arranged inside the cylindrical member 110.

[0020] The cylindrical member 110 has an outer circumferential surface 110a and an inner circumferential surface 110b. The outer circumferential surface 110a has a circular cross-section and extends in the longitudinal direction L. The inner circumferential surface 110b also has a circular cross-section and extends in the longitudinal direction L.

[0021] For example, the cylindrical member 110 is formed from resin. Typically, the cylindrical member 110 is formed by resin molding.

[0022] The light source substrate 120 is in the form of a thin plate. The light source substrate 120 has a main surface that extends in the XY plane. The light source substrate 120 extends in the longitudinal direction L along the Y direction. The length of the light source substrate 120 along the Y direction is greater than the length (width) of the light source substrate 120 along the X direction. Also, the length (width) of the light source substrate 120 along the X direction is greater than the length (thickness) of the light source substrate 120 along the Z direction.

[0023] A light source 122 is arranged on the light source substrate 120. The light source 122 emits light. Typically, multiple light sources 122 are arranged on the light source substrate 120. Here, the multiple light sources 122 are arranged in two rows along the longitudinal direction L on the light source substrate 120. Alternatively, the multiple light sources 122 may be arranged in two or more rows along the longitudinal direction L on the light source substrate 120.

[0024] The light source substrate 120 has conductive wiring provided on an insulating substrate. The light source 122 is installed at the end of the conductive wiring.

[0025] The light source 122 is positioned on the main surface of the light source substrate 120 facing the +Z direction. The light source 122 emits light in the +Z direction.

[0026] The substrate holding member 130 extends in the longitudinal direction L. The substrate holding member 130 holds the light source substrate 120. The light source substrate 120 is mounted in a predetermined position on the substrate holding member 130 and is held by the substrate holding member 130. The substrate holding member 130 is mounted on the inner circumferential surface 110b of the cylindrical member 110. The shape of the cylindrical member 110 is maintained by the substrate holding member 130.

[0027] The substrate holding member 130 may be composed of a heat dissipation member, and the substrate holding member 130 may function as a heat sink. In this case, the thermal conductivity of the substrate holding member 130 is higher than that of the light source substrate 120. Also, the thermal conductivity of the substrate holding member 130 is higher than that of the cylindrical member 110. For example, the substrate holding member 130 is formed from aluminum. Typically, the substrate holding member 130 is formed by extrusion molding.

[0028] The mounting portion 140 includes an end cover 141, a mouthpiece 142, and a fastener 143. The end cover 141 covers the end of the cylindrical member 110. The end cover 141 is cylindrical with one main surface recessed. The end cover 141 is attached to the end of the cylindrical member 110.

[0029] The base 142 protrudes outward from the end cover 141. The base 142 is conductive. The base 142 electrically connects the power supply of a lighting fixture (not shown) to the light source substrate 120. Power is supplied from the external power supply to the light source 122 on the light source substrate 120 via the base 142.

[0030] The end cover 141 is provided with a through hole 140p. The fastener 143 is fitted into the through hole 140p of the end cover 141. The fastener 143 is attached to a predetermined portion of the substrate holding member 130 via the end cover 141.

[0031] For example, the substrate holding member 130 is mounted to the cylindrical member 110 by sliding it. Typically, the substrate holding member 130 is mounted to the cylindrical member 110 by sliding it in the +Y direction relative to the inner circumferential surface 110b.

[0032] Furthermore, the light source substrate 120 on which the light source 122 is placed is mounted to the substrate holding member 130 by sliding it. Typically, the light source substrate 120 is mounted to the substrate holding member 130 by sliding it in the +Y direction with respect to the light source 122.

[0033] Next, the straight tube lamp 100 of this embodiment will be described with reference to Figures 1 to 3A. Figure 3A is a schematic cross-sectional view of the straight tube lamp 100 of this embodiment.

[0034] As shown in Figure 3A, the straight tube lamp 100 includes a light source substrate 120 on which light sources 122 are arranged in two rows. The light sources 122 are positioned on the main surface of the light source substrate 120 in the +Z direction. The light source substrate 120 is mounted on a substrate holding member 130.

[0035] The cylindrical member 110 has an outer circumferential surface 110a and an inner circumferential surface 110b. The cross-section of the outer circumferential surface 110a is circular. The cross-section of the inner circumferential surface 110b is circular and has the same central axis as the outer circumferential surface 110a.

[0036] The substrate holding member 130 is positioned inside the cylindrical member 110. The substrate holding member 130 is located on the -Z side of the inner circumferential surface 110b of the cylindrical member 110. The substrate holding member 130 is attached to the inner circumferential surface 110b of the cylindrical member 110. The substrate holding member 130 is positioned along a portion of the inner circumferential surface 110b of the cylindrical member 110.

[0037] For example, when a light source substrate 120 on which a light source 122 is placed is mounted on a substrate holding member 130, the light source 122 is exposed without being covered by the substrate holding member 130.

[0038] In the straight tube lamp 100, the cylindrical member 110 and the substrate holding member 130 have a symmetrical structure with respect to the Z axis.

[0039] Next, the cylindrical member 110 in the straight tube lamp 100 of this embodiment will be described with reference to Figures 1 to 3B. Figure 3B is a schematic cross-sectional view of the cylindrical member 110 in the straight tube lamp 100 of this embodiment.

[0040] As shown in Figure 3B, the cylindrical member 110 has projections 112 in addition to its outer circumferential surface 110a and inner circumferential surface 110b. The projections 112 protrude inward from the inner circumferential surface 110b. More specifically, the projections 112 protrude inward from both sides of the inner circumferential surface 110b. The two projections 112 face each other. One projection 112 protrudes inward from a certain portion of the inner circumferential surface 110b located on the +X side. The other projection 112 protrudes inward from a certain portion of the inner circumferential surface 110b located on the -X side.

[0041] As can be seen from Figures 3A and 3B, the projection 112 of the cylindrical member 110 engages with the side of the substrate holding member 130. The substrate holding member 130 is mounted on the cylindrical member 110 via the projection 112 of the cylindrical member 110.

[0042] Next, the substrate holding member 130 in the straight tube lamp 100 of this embodiment will be described with reference to Figures 1 to 4A. Figure 4A is a schematic cross-sectional view of the substrate holding member 130 in the straight tube lamp 100 of this embodiment.

[0043] The substrate holding member 130 has a reference portion 132, a projection portion 134, and a connecting portion 136. The reference portion 132 has a flat surface extending in the XY plane. The normal to the surface of the reference portion 132 on the +Z direction side extends in the +Z direction, and the reference portion 132 faces in the +Z direction.

[0044] The connecting portion 136 extends from the reference portion 132 in the +Z direction. The connecting portion 136 connects the reference portion 132 and the projection portion 134. The connecting portion 136 connects the reference portion 132 and the projection portion 134 on the side of the reference portion 132 in the +X direction. In addition, the connecting portion 136 connects the reference portion 132 and the projection portion 134 on the side of the reference portion 132 in the -X direction. Thus, the connecting portion 136 is located at the left and right ends of the reference portion 132.

[0045] The left and right protrusions 134 project inward from the left and right connecting portions 136. Therefore, the length (distance) along the X direction between the left and right protrusions 134 is smaller than the length (distance) along the X direction between the left and right connecting portions 136.

[0046] The projection 134 protrudes from the connecting portion 136 in the -X direction on the +X side of the reference portion 132 and faces the reference portion 132 on the +Z side. Also, the projection 134 protrudes from the connecting portion 136 in the +X direction on the -X side of the reference portion 132 and faces the reference portion 132 on the +Z side. In this way, the projection 134 faces the left and right ends of the reference portion 132.

[0047] The light source substrate 120 is placed within the space formed by the reference portion 132, projection portion 134, and connecting portion 136 of the substrate holding member 130.

[0048] In the straight tube lamp 100 of this embodiment, the substrate holding member 130 is provided with a stepped portion 130s. Here, the stepped portion 130s is provided on each of the left and right projections 134. Therefore, the stepped portion 130s is located on the +X direction side and the -X direction side with respect to the reference portion 132. The stepped portion 130s is provided on the surface of the projection 134 that faces the reference portion 132.

[0049] The stepped portion 130s has a first opposing surface 130s1, an intersecting surface 130s2, and a second opposing surface 130s3. The intersecting surface 130s2 is in contact with the first opposing surface 130s1. The second opposing surface 130s3 is also in contact with the intersecting surface 130s2. The intersecting surface 130s2 is located between the first opposing surface 130s1 and the second opposing surface 130s3.

[0050] The first opposing surface 130s1 faces the reference portion 132. The first opposing surface 130s1 extends in the XY plane. For example, the first opposing surface 130s1 is located at the tip (inside) of the projection 134. More specifically, the first opposing surface 130s1 is located away from the connecting portion 136 on the projection 134.

[0051] The intersecting surface 130s2 intersects with the first opposing surface 130s1. Here, the intersecting surface 130s2 is perpendicular to the first opposing surface 130s1.

[0052] The second opposing surface 130s3 extends parallel to the first opposing surface 130s1. The second opposing surface 130s3 extends in the XY plane. The second opposing surface 130s3 faces the reference portion 132. For example, the second opposing surface 130s3 is located on the connection portion 136 side (outside) of the projection portion 134. The second opposing surface 130s3 intersects with the intersecting surface 130s2. Here, the second opposing surface 130s3 is perpendicular to the intersecting surface 130s2.

[0053] The second opposing surface 130s3 is located closer to the reference portion 132 than the first opposing surface 130s1. The distance (spacing) along the Z direction between the second opposing surface 130s3 and the reference portion 132 is smaller than the distance (spacing) along the Z direction between the first opposing surface 130s1 and the reference portion 132.

[0054] Furthermore, the length L1 of the first opposing surface 130s1 along the X direction is greater than the length L2 of the intersecting surface 130s2 along the Z direction. Therefore, as will be described later with reference to Figures 5A and 5B, the light source substrate 120A can be mounted more stably when it is mounted in contact with the first opposing surface 130s1.

[0055] Furthermore, the length L1 of the first opposing surface 130s1 along the X direction is smaller than the length L3 of the second opposing surface 130s3 along the X direction. Therefore, when the light source substrate 120 on which the light source 122 is placed is mounted on the substrate holding member 130, the shadows cast by the light emitted from the light source 122 hitting the protrusions 134 of the substrate holding member 130 are suppressed.

[0056] A recess 134p is provided on the +Z direction side of the projection 134. This prevents a specific part of the projection 134 from becoming excessively thick. In addition, the recess 134p of the projection 134 increases the surface area of ​​the substrate holding member 130, thereby improving the heat dissipation function of the substrate holding member 130.

[0057] The projection 134 has an inclined surface 134s. The inclined surface 134s is obliquely inclined from the inside outward in the -Z direction to the +Z direction. The angle that the inclined surface 134s makes with respect to the XY plane is acute. Therefore, the shadow cast by light emitted from the light source 122 hitting the projection 134 of the substrate holding member 130 is suppressed.

[0058] The connecting portion 136 has an inner wall 136w. The length (spacing) along the X direction between the left and right inner walls 136w is greater than the length (spacing) along the X direction between the left and right intersecting surfaces 130s2. Also, the length (spacing) along the X direction between the left and right inner walls 136w is greater than or equal to the length (width) along the X direction of the light source substrate 120. In this specification, the X direction perpendicular to the longitudinal direction L along the Y direction (Figure 1) and the normal direction of the reference portion 132 along the Z direction may be described as the width direction.

[0059] The substrate holding member 130 further includes a main body portion 131 and an engaging portion 138, in addition to the reference portion 132, projection portion 134, and connecting portion 136. The main body portion 131 is located in the -Z direction relative to the reference portion 132. The main body portion 131 has an outer surface with a circular arc cross-section that faces the inner circumferential surface 110b of the cylindrical member 110.

[0060] The engaging portion 138 is located on the outside of the connecting portion 136. The engaging portion 138 has a U-shaped cross-section. The engaging portion 138 engages with the projection 112 of the cylindrical member 110.

[0061] The main body portion 131 is provided with a cutout 130p. The cutout 130p extends in the Y direction and widens in the X direction. The cutout 130p prevents certain parts of the main body portion 131 from becoming excessively thick. In addition, the cutout 130p reduces the amount of material used for the substrate holding member 130 and increases the surface area of ​​the substrate holding member 130, thereby improving the heat dissipation function of the substrate holding member 130.

[0062] Furthermore, the main body 131 is provided with a fastening hole 130h. The fastening hole 130h is located in the center of the cutout hole 130p. The fastening hole 130h has a circular arc cross-section. The fastener 143 (Figure 2) is fastened to the fastening hole 130h. In addition, the fastening hole 130h increases the surface area of ​​the substrate holding member 130, thereby increasing the heat dissipation function of the substrate holding member 130.

[0063] Next, the light source substrate 120 and substrate holding member 130 in the straight tube lamp 100 of this embodiment will be described with reference to Figures 1 to 4B. Figure 4B is a schematic cross-sectional view of the light source substrate 120 and substrate holding member 130 in the straight tube lamp 100 of this embodiment.

[0064] As shown in Figure 4B, the straight tube lamp 100 has a light source substrate 120 in which light sources 122 are arranged in two rows, which is attached to a substrate holding member 130.

[0065] The light source substrate 120 is in the shape of a thin plate. The light source substrate 120 has a first main surface 120a, a second main surface 120b, a side surface 120c1, and a side surface 120c2. The first main surface 120a is located on the +Z direction side, and the second main surface 120b is located on the -Z direction side. The side surface 120c1 is located on the +X direction side, and the side surface 120c2 is located on the -X direction side.

[0066] The normal to the first principal surface 120a extends in the +Z direction, and the first principal surface 120a faces in the +Z direction. A light source 122 is positioned on the first principal surface 120a.

[0067] The second principal surface 120b is located on the opposite side of the first principal surface 120a. The second principal surface 120b is a different principal surface from the first principal surface 120a on which the light source 122 is located. The normal of the second principal surface 120b extends in the -Z direction, and the second principal surface 120b faces in the -Z direction.

[0068] Sides 120c1 and 120c2 extend in the longitudinal direction L. Sides 120c1 and 120c2 connect the first principal surface 120a and the second principal surface 120b. The normal to side 120c1 extends in the +X direction, and side 120c1 faces in the +X direction. The normal to side 120c2 extends in the -X direction, and side 120c2 faces in the -X direction.

[0069] As described above, the substrate holding member 130 holds the light source substrate 120. The reference portion 132 faces the second main surface 120b of the light source substrate 120. The projection portion 134 faces the first main surface 120a of the light source substrate 120.

[0070] The light source substrate 120 is mounted on the substrate holding member 130. When the light source substrate 120 is mounted on the substrate holding member 130, the main surface 120a of the light source substrate 120 contacts the second opposing surface 130s3 of the stepped portion 130s in the substrate holding member 130. More precisely, the main surface 120a of the light source substrate 120 does not contact the second opposing surface 130s3 of the stepped portion 130s in the substrate holding member 130, and there may be a gap between the main surface 120a and the second opposing surface 130s3 of the stepped portion 130s in the substrate holding member 130.

[0071] Furthermore, when the light source substrate 120 is mounted on the substrate holding member 130, the main surface 120b of the light source substrate 120 contacts the reference portion 132 of the substrate holding member 130. Strictly speaking, the main surface 120b of the light source substrate 120 does not contact the reference portion 132 of the substrate holding member 130, and there may be a gap between the main surface 120b and the reference portion 132 of the substrate holding member 130.

[0072] When the light source substrate 120 is mounted on the substrate holding member 130, the side surface 120c1 of the light source substrate 120 faces the inner wall 136w of the connection portion 136 of the substrate holding member 130. The side surface 120c1 of the light source substrate 120 may also be in contact with the inner wall 136w of the connection portion 136 of the substrate holding member 130.

[0073] Similarly, when the light source substrate 120 is mounted on the substrate holding member 130, the side surface 120c2 of the light source substrate 120 faces the inner wall 136w of the connection portion 136 of the substrate holding member 130. The side surface 120c2 of the light source substrate 120 may also be in contact with the inner wall 136w of the connection portion 136 of the substrate holding member 130.

[0074] Thus, the substrate holding member 130 has a mounting surface 130c that contacts or faces the light source substrate 120 when the light source substrate 120 is mounted on the substrate holding member 130. Here, the substrate holding member 130 contacts the light source substrate 120 on three surfaces. Specifically, the substrate holding member 130 contacts the light source substrate 120 with the surface of the reference portion 132 on the +Z direction side, the surface of the stepped portion 130s of the projection 134 on the +X direction and -Z direction side (second opposing surface 130s3), and the surface of the stepped portion 130s of the projection 134 on the -X direction and -Z direction side (second opposing surface 130s3).

[0075] Therefore, the mounting surface 130c on the substrate holding member 130 to which the light source substrate 120 is attached consists of the surface on the +Z direction side of the reference portion 132, the surface on the +X direction and -Z direction side of the stepped portion 130s of the projection portion 134 (second opposing surface 130s3), and the surface on the -X direction and -Z direction side of the stepped portion 130s of the projection portion 134 (second opposing surface 130s3).

[0076] Thus, at the stepped portion 130s on the +X direction side of the substrate holding member 130, the second opposing surface 130s3 is located on the +X direction and -Z direction side of the projection 134, and contacts the light source substrate 120 when the light source substrate 120 is mounted on the substrate holding member 130. Therefore, the stepped portion 130s of the substrate holding member 130 is connected to the mounting surface 130c on the substrate holding member 130 to which the light source substrate 120 is mounted. Also, at the stepped portion 130s on the -X direction side of the substrate holding member 130, the second opposing surface 130s3 is located on the -X direction and -Z direction side of the projection 134, and contacts the light source substrate 120 when the light source substrate 120 is mounted on the substrate holding member 130. Therefore, the stepped portion 130s of the substrate holding member 130 is connected to the mounting surface 130c on which the light source substrate 120 is mounted.

[0077] In this example, the stepped portion 130s is provided on the projection 134 of the substrate holding member 130, but the stepped portion 130s may be provided on a part other than the projection 134 of the substrate holding member 130. For example, the stepped portion 130s may be provided on the reference portion 132 of the substrate holding member 130. Alternatively, the stepped portion 130s may be provided on at least one of the projection 134 and the reference portion 132 of the substrate holding member 130.

[0078] The straight tube lamp 100 of this embodiment comprises a cylindrical member 110 extending in the longitudinal direction L, a light source substrate 120 on which a light source 122 is arranged, and a substrate holding member 130 arranged inside the cylindrical member 110 and holding the light source substrate 120. The substrate holding member 130 has a stepped portion 130s connected to the mounting surface 130c on which the light source substrate 120 is mounted. As a result, as will be described in detail later, the straight tube lamp 100 can suitably mount light source substrates of different widths.

[0079] Furthermore, in the straight tube lamp 100 of this embodiment, the substrate holding member 130 includes a heat dissipation member that dissipates the heat generated in the light source substrate 120. As a result, the substrate holding member 130 can quickly release the heat generated in the light source substrate 120 to the outside.

[0080] Furthermore, in the straight tube lamp 100 of this embodiment, the light source substrate 120 has a first main surface 120a on which the light source 122 is arranged, and a second main surface 120b different from the first main surface 120a. The substrate holding member 130 has a projection 134 facing the first main surface 120a of the light source substrate 120, a reference portion 132 facing the second main surface 120b of the light source substrate 120, and a connecting portion 136 connecting the reference portion 132 and the projection 134. The stepped portion 130s may be provided on at least one of the projection 134 and the reference portion 132. For example, the stepped portion 130s may be provided on the projection 134. This allows the straight tube lamp 100 to suitably mount light source substrates of different widths.

[0081] Furthermore, in the straight tube lamp 100 of this embodiment, the stepped portion 130s has a first opposing surface 130s1 facing the reference portion 132, an intersecting surface 130s2 that intersects with the first opposing surface 130s1, and a second opposing surface 130s3 that faces the reference portion 130s1, intersects with the intersecting surface 130s2, and is located closer to the connection portion 136 than the first opposing surface 130s1. This makes it easy to form a stepped portion 130s that can suitably mount light source substrates of different widths.

[0082] Furthermore, in the straight tube lamp 100 of this embodiment, the length of the first opposing surface 130s1 is smaller than the length of the second opposing surface 130s3 in the width direction perpendicular to the longitudinal direction L and the normal direction of the reference portion 132. This suppresses the occurrence of shadows when light emitted from the light source 122 strikes the substrate holding member 130.

[0083] In the above description with reference to Figures 1 to 4B, the light source substrate 120 in the straight tube lamp 100 of this embodiment is mounted on the substrate holding member 130, but a light source substrate different from the light source substrate 120 may be mounted on the substrate holding member 130.

[0084] Next, the straight tube lamp 100 of this embodiment will be described with reference to Figures 1 to 5B. Figure 5A is a schematic cross-sectional view of the straight tube lamp 100 of this embodiment, and Figure 5B is a schematic cross-sectional view of the light source substrate 120A and the substrate holding member 130 in the straight tube lamp 100 of Figure 5A. The straight tube lamp 100 shown in Figures 5A and 5B has the same configuration as the straight tube lamp 100 described above with reference to Figures 3A and 4B, except that a light source substrate 120A, which is different from the light source substrate 120, is mounted on the substrate holding member 130, and redundant explanations will be omitted to avoid redundancy.

[0085] As shown in Figure 5A, the straight tube lamp 100 comprises a cylindrical member 110, a light source substrate 120A, and a substrate holding member 130. The light source substrate 120A and the substrate holding member 130 are arranged inside the cylindrical member 110. In the straight tube lamp 100, light sources 122 are arranged in a single row on the light source substrate 120A. The light source substrate 120A is mounted on the substrate holding member 130.

[0086] As can be seen from comparing Figure 3A and Figure 5A, in Figure 3A, the light source substrate 120 is mounted on the substrate holding member 130, while in Figure 5A, the light source substrate 120A is mounted on the substrate holding member 130. The length (width) of the light source substrate 120A along the X direction is smaller than the length (width) of the light source substrate 120 along the X direction. Also, the length (thickness) of the light source substrate 120A along the Z direction is larger than the length (thickness) of the light source substrate 120 along the Z direction.

[0087] As shown in Figure 5B, the straight tube lamp 100 has a light source substrate 120A in which light sources 122 are arranged in a single row, which is attached to the substrate holding member 130.

[0088] The light source substrate 120A is a flat plate extending in the longitudinal direction. A light source 122 is placed on the light source substrate 120A. The light source substrate 120A is mounted on the substrate holding member 130.

[0089] As described above, the length (width) of the light source substrate 120A along the X direction is smaller than the length (width) of the light source substrate 120 along the X direction. Also, the length (thickness) of the light source substrate 120A along the Z direction is larger than the length (thickness) of the light source substrate 120 along the Z direction.

[0090] The light source substrate 120A has a first main surface 120a, a second main surface 120b, a side surface 120c1, and a side surface 120c2. The length (width) of the first main surface 120a and the second main surface 120b of the light source substrate 120A along the X direction is smaller than the length (width) of the first main surface 120a and the second main surface 120b of the light source substrate 120 along the X direction. Also, the length (thickness) of the side surfaces 120c1 and 120c2 of the light source substrate 120A along the Z direction is larger than the length (thickness) of the side surfaces 120c1 and 120c2 of the light source substrate 120 along the Z direction.

[0091] The main surface 120a of the light source substrate 120A is in contact with the first opposing surface 130s1 of the stepped portion 130s of the substrate holding member 130. More precisely, the main surface 120a of the light source substrate 120A may not be in contact with the first opposing surface 130s1 of the stepped portion 130s of the substrate holding member 130, and there may be a gap between the main surface 120a and the first opposing surface 130s1 of the stepped portion 130s of the substrate holding member 130.

[0092] Furthermore, the main surface 120b of the light source substrate 120A is in contact with the reference portion 132 of the substrate holding member 130. Strictly speaking, the main surface 120b of the light source substrate 120A may not be in contact with the reference portion 132 of the substrate holding member 130, and there may be a gap between them.

[0093] The side surface 120c1 of the light source substrate 120A faces the intersecting surface 130s2 of the stepped portion 130s in the substrate holding member 130. The side surface 120c1 of the light source substrate 120A may also be in contact with the intersecting surface 130s2 of the stepped portion 130s in the substrate holding member 130.

[0094] Similarly, the side surface 120c2 of the light source substrate 120A faces the intersecting surface 130s2 of the stepped portion 130s in the substrate holding member 130. The side surface 120c2 of the light source substrate 120A may also be in contact with the intersecting surface 130s2 of the stepped portion 130s in the substrate holding member 130.

[0095] Thus, the substrate holding member 130 has a mounting surface 130c that contacts or faces the light source substrate 120A when the light source substrate 120A is mounted on the substrate holding member 130. The substrate holding member 130 contacts the light source substrate 120A on three surfaces. Specifically, the substrate holding member 130 contacts the light source substrate 120A with the surface of the reference portion 132 on the +Z direction side, the surface of the stepped portion 130s of the projection 134 on the +X direction and +Z direction side (first opposing surface 130s1), and the surface of the stepped portion 130s of the projection 134 on the -X direction and +Z direction side (first opposing surface 130s1).

[0096] Therefore, the mounting surface 130c on the substrate holding member 130 to which the light source substrate 120A is mounted consists of the surface on the +Z direction side of the reference portion 132, the surface on the +X direction and +Z direction side of the stepped portion 130s of the projection portion 134 (first opposing surface 130s1), and the surface on the -X direction and +Z direction side of the stepped portion 130s of the projection portion 134 (first opposing surface 130s1).

[0097] Thus, at the stepped portion 130s on the +X direction side of the substrate holding member 130, the first opposing surface 130s1 is located on the +X and +Z direction side of the projection 134, and contacts the light source substrate 120A when the light source substrate 120 is mounted on the substrate holding member 130. Therefore, the stepped portion 130s of the substrate holding member 130 is connected to the mounting surface 130c on the substrate holding member 130 where the light source substrate 120A is mounted. Also, at the stepped portion 130s on the -X direction side of the substrate holding member 130, the first opposing surface 130s1 is located on the -X and +Z direction side of the projection 134, and contacts the light source substrate 120A when the light source substrate 120A is mounted on the substrate holding member 130. Therefore, the stepped portion 130s of the substrate holding member 130 is connected to the mounting surface 130c on the substrate holding member 130 where the light source substrate 120A is mounted.

[0098] In the straight tube lamp 100 of this embodiment, the substrate holding member 130 can appropriately mount either the light source substrate 120 or the light source substrate 120A due to the stepped portion 130s. Specifically, the light source substrate 120 can be mounted on the second opposing surface 130s3 of the stepped portion 130s in the substrate holding member 130, and the light source substrate 120A can be mounted on the first opposing surface 130s1 of the stepped portion 130s in the substrate holding member 130. Therefore, in the straight tube lamp 100 of this embodiment, the same substrate holding member 130 can be used to mount light source substrates 120 and 120A, which have different widths and thicknesses.

[0099] Therefore, with the straight tube lamp 100 of this embodiment, both the light source substrate 120 and the light source substrate 120A can be properly mounted using a single type of substrate holding member 130. As a result, there is no need to manufacture different substrate holding members depending on the type of light source substrate, and the increase in the number of parts can be suppressed.

[0100] Furthermore, it is preferable that the substrate holding member 130 can accommodate an optical substrate of a size conforming to the standard. Typically, a substrate with a width of 13 mm and a thickness of 1.0 mm is preferably used as the wide and thin light source substrate 120, and a substrate with a width of 10 mm and a thickness of 1.6 mm is preferably used as the narrow and thick light source substrate 120A.

[0101] Typically, the substrate holding member 130 is formed by extrusion molding, while the light source substrates 120 and 120A are formed by cutting a large substrate. Therefore, when designing the substrate holding member according to the type of light source substrate 120 and 120A, it is necessary to manufacture a number of molds for the substrate holding member corresponding to the type of light source substrate 120 and 120A. According to this embodiment, since both the light source substrate 120 and 120A can be mounted on the substrate holding member 130, parts can be standardized, and the occurrence of unnecessary costs can be suppressed.

[0102] In the straight tube lamp 100 of this embodiment, a stepped portion 130s is provided on the projection 134 of the substrate holding member 130, and the reference portion 132 of the substrate holding member 130 contacts the light source substrates 120 and 120A over a wide area. Therefore, even if heat is generated in the light source substrates 120 and 120A, the substrate holding member 130 can quickly dissipate the heat to the outside via the reference portion 132.

[0103] In the above description with reference to Figures 1 to 5B, the stepped portion 130s of the substrate holding member 130 was provided on the projection 134, but this embodiment is not limited to this. The substrate holding member 130 may also be provided with stepped portions 130s other than the projection 134.

[0104] [Second Embodiment] Next, the straight tube lamp 100A of this embodiment will be described with reference to Figures 6 to 8B. Figure 6 is a schematic cross-sectional view of the straight tube lamp 100A of this embodiment. The straight tube lamp 100A shown in Figure 6 has the same configuration as the straight tube lamp 100 described above with reference to Figure 3A, except that the stepped portion 130s is provided on the reference portion 132 instead of the stepped portion 130s provided on the projection portion 134 of the substrate holding member 130, and redundant explanations will be omitted to avoid redundancy.

[0105] As shown in Figure 6, the straight tube lamp 100A comprises a cylindrical member 110, a light source substrate 120, and a substrate holding member 130A. The light source substrate 120 and the substrate holding member 130A are arranged inside the cylindrical member 110.

[0106] A light source substrate 120, on which light sources 122 are arranged in two rows, is placed in the straight tube lamp 100A. The light source substrate 120 is mounted on a substrate holding member 130A. The substrate holding member 130A is mounted on the inner circumferential surface 110b of the cylindrical member 110.

[0107] Next, the substrate holding member 130A in the straight tube lamp 100A of this embodiment will be described with reference to Figures 6 and 7A. Figure 7A is a schematic cross-sectional view of the substrate holding member 130A in the straight tube lamp 100A of this embodiment. The substrate holding member 130A shown in Figure 7A has the same configuration as the substrate holding member 130 described above with reference to Figure 4A, except that the stepped portion 130s is provided on the reference portion 132, and redundant explanations will be omitted to avoid redundancy.

[0108] As shown in Figure 7A, the substrate holding member 130A has a reference portion 132, a projection portion 134, and a connecting portion 136. The reference portion 132 has a flat surface that extends in the XY plane.

[0109] The connecting portion 136 extends from the reference portion 132 in the +Z direction. The connecting portion 136 connects the reference portion 132 and the projection portion 134. The connecting portion 136 connects the reference portion 132 and the projection portion 134 on the side of the reference portion 132 in the +X direction. In addition, the connecting portion 136 connects the reference portion 132 and the projection portion 134 on the side of the reference portion 132 in the -X direction. Thus, the connecting portion 136 is located to the left and right of the reference portion 132.

[0110] The length (distance) along the X direction between the left and right protrusions 134 is smaller than the length (distance) along the X direction between the left and right connecting portions 136. The light source substrate 120 is positioned within the space formed by the reference portion 132, protrusions 134, and connecting portion 136 of the substrate holding member 130A.

[0111] The projection 134 protrudes from the connecting portion 136 toward the -X direction on the +X side of the reference portion 132 and faces the reference portion 132 toward the +Z direction. Also, the projection 134 protrudes from the connecting portion 136 toward the +X direction on the -X side of the reference portion 132 and faces the reference portion 132 toward the +Z direction. Thus, the projection 134 is located to the left and right of the reference portion 132. The face of the projection 134 toward the -Z direction extends in the XY plane.

[0112] In the straight tube lamp 100A of this embodiment, the stepped portion 130s is provided on the reference portion 132. The stepped portion 130s is provided on the surface of the reference portion 132 on the +Z direction side.

[0113] The stepped portion 130s has a first opposing surface 130s1, an intersecting surface 130s2, and a second opposing surface 130s3. The intersecting surface 130s2 is in contact with the first opposing surface 130s1. The second opposing surface 130s3 is also in contact with the intersecting surface 130s2. The intersecting surface 130s2 is located between the first opposing surface 130s1 and the second opposing surface 130s3.

[0114] The first opposing surface 130s1 faces the projection 134. For example, the first opposing surface 130s1 is located in the center (inside) of the reference portion 132. More specifically, the first opposing surface 130s1 is located away from the connecting portion 136 in the reference portion 132. The first opposing surface 130s1 faces the -Z direction side of the projection 134 and extends in the XY plane.

[0115] The intersecting surface 130s2 intersects with the first opposing surface 130s1. Here, the intersecting surface 130s2 is perpendicular to the first opposing surface 130s1.

[0116] The second opposing surface 130s3 faces the projection 134. The second opposing surface 130s3 extends parallel to the first opposing surface 130s1. For example, the second opposing surface 130s3 is located outside the reference portion 132. More specifically, the first opposing surface 130s1 is located near the connecting portion 136 in the reference portion 132. The second opposing surface 130s3 intersects with the intersecting surface 130s2. Here, the second opposing surface 130s3 is perpendicular to the intersecting surface 130s2.

[0117] The second opposing surface 130s3 is located closer to the projection 134 than the first opposing surface 130s1. The length (distance) along the Z direction between the second opposing surface 130s3 and the projection 134 is smaller than the length (distance) along the Z direction between the first opposing surface 130s1 and the projection 134.

[0118] The projection 134 has an inclined surface 134s. The inclined surface 134s is obliquely inclined from the inside outward in the -Z direction to the +Z direction. The angle that the inclined surface 134s makes with respect to the XY plane is acute. Therefore, the shadow cast by light emitted from the light source 122 hitting the projection 134 of the substrate holding member 130 is suppressed.

[0119] The connecting portion 136 has an inner wall 136w. The length (spacing) along the X direction between the left and right inner walls 136w is greater than or equal to the length (width) along the X direction of the light source substrate 120. Also, the length (spacing) along the X direction between the left and right inner walls 136w is greater than the length (spacing) along the X direction between the left and right intersecting surfaces 130s2.

[0120] Next, the light source substrate 120 and substrate holding member 130A in the straight tube lamp 100A of this embodiment will be described with reference to Figures 6 to 7B. Figure 7B is a schematic cross-sectional view of the light source substrate 120 and substrate holding member 130A in the straight tube lamp 100A of this embodiment. The light source substrate 120 and substrate holding member 130A shown in Figure 7B have the same configuration as the light source substrate 120 and substrate holding member 130 described above with reference to Figure 4B, except that the stepped portion 130s is provided on the reference portion 132, and redundant explanations will be omitted to avoid redundancy.

[0121] As shown in Figure 7B, the straight tube lamp 100 has a light source substrate 120 in which light sources 122 are arranged in two rows, which is attached to a substrate holding member 130A.

[0122] The light source substrate 120 is in the shape of a thin plate. The light source substrate 120 has a first main surface 120a, a second main surface 120b, a side surface 120c1, and a side surface 120c2.

[0123] The main surface 120a of the light source substrate 120 is in contact with the projection 134 of the substrate holding member 130A. Alternatively, the main surface 120a of the light source substrate 120 may not be in contact with the projection 134 of the substrate holding member 130A, and there may be a gap between the two surfaces.

[0124] The main surface 120b of the light source substrate 120 is in contact with the second opposing surface 130s3 of the stepped portion 130s of the substrate holding member 130A. Alternatively, the main surface 120b of the light source substrate 120 may not be in contact with the second opposing surface 130s3 of the stepped portion 130s of the substrate holding member 130A, and there may be a gap between it and the second opposing surface 130s3 of the stepped portion 130s of the substrate holding member 130A.

[0125] The side surface 120c1 of the light source substrate 120 faces the inner wall 136w of the connection portion 136 of the substrate holding member 130A. The side surface 120c1 of the light source substrate 120 may also be in contact with the inner wall 136w of the connection portion 136 of the substrate holding member 130A.

[0126] Similarly, the side surface 120c2 of the light source substrate 120 faces the inner wall 136w of the connection portion 136 of the substrate holding member 130A. The side surface 120c2 of the light source substrate 120 may also be in contact with the inner wall 136w of the connection portion 136 of the substrate holding member 130A.

[0127] Thus, the substrate holding member 130A has a mounting surface 130c that contacts or faces the light source substrate 120 when the light source substrate 120 is mounted on the substrate holding member 130A. The substrate holding member 130A contacts the light source substrate 120 on four surfaces. Specifically, the substrate holding member 130A contacts the light source substrate 120 with the +X and +Z side surface (second opposing surface 130s3) of the stepped portion 130s in the reference portion 132, the -X and +Z side surface (second opposing surface 130s3) of the stepped portion 130s in the reference portion 132, the +X and -Z side surface of the projection 134, and the -X and -Z side surface of the projection 134.

[0128] Therefore, the mounting surface 130c on the substrate holding member 130A to which the light source substrate 120 is mounted consists of the +X and +Z side surface (second opposing surface 130s3) of the stepped portion 130s in the reference portion 132, the -X and +Z side surface (second opposing surface 130s3) of the stepped portion 130s in the reference portion 132, the +X and -Z side surface of the projection 134, and the -X and -Z side surface of the projection 134.

[0129] Thus, at the stepped portion 130s on the +X direction side of the substrate holding member 130A, the second opposing surface 130s3 is located on the +X and +Z direction side of the reference portion 132, and contacts the light source substrate 120 when the light source substrate 120 is mounted on the substrate holding member 130A. Therefore, the stepped portion 130s in the substrate holding member 130A is connected to the mounting surface 130c on the substrate holding member 130A to which the light source substrate 120 is mounted. Also, at the stepped portion 130s on the -X direction side of the substrate holding member 130A, the second opposing surface 130s3 is located on the -X and +Z direction side of the reference portion 132, and contacts the light source substrate 120 when the light source substrate 120 is mounted on the substrate holding member 130A. Therefore, the stepped portion 130s in the substrate holding member 130A is connected to the mounting surface 130c on the substrate holding member 130A to which the light source substrate 120 is mounted.

[0130] In the above description with reference to Figures 6 to 7B, in the straight tube lamp 100A of this embodiment, the light source substrate 120 is attached to the substrate holding member 130A, but a light source substrate different from the light source substrate 120 may be attached to the substrate holding member 130A.

[0131] Next, the straight tube lamp 100A of this embodiment will be described with reference to Figures 6 to 8B. Figure 8A is a schematic cross-sectional view of the straight tube lamp 100A of this embodiment, and Figure 8B is a schematic cross-sectional view of the light source substrate 120A and the substrate holding member 130A in the straight tube lamp 100A of Figure 8A. The straight tube lamp 100 shown in Figures 8A and 8B has the same configuration as the straight tube lamp 100A described above with reference to Figures 6 and 7B, except that a light source substrate 120A, which is different from the light source substrate 120, is mounted on the substrate holding member 130A, and redundant explanations will be omitted to avoid redundancy.

[0132] Furthermore, comparing Figures 6 and 7B with Figures 8A and 8B, the straight tube lamp 100A shown in Figures 6 and 7B has a light source substrate 120, while the straight tube lamp 100A shown in Figures 8A and 8B has a light source substrate 120A.

[0133] As shown in Figure 8A, the straight tube lamp 100A comprises a cylindrical member 110, a light source substrate 120A, and a substrate holding member 130A. In the straight tube lamp 100A, light sources 122 are arranged in a single row on the light source substrate 120A. The light source substrate 120A and the substrate holding member 130A are placed inside the cylindrical member 110. The light source substrate 120A is mounted on the substrate holding member 130A.

[0134] As can be seen from comparing Figure 6 and Figure 8A, in Figure 6, the light source substrate 120 is mounted on the substrate holding member 130A, whereas in Figure 8A, the light source substrate 120A is mounted on the substrate holding member 130A. The length (width) of the light source substrate 120A along the X direction is smaller than the length (width) of the light source substrate 120 along the X direction. Also, the length (thickness) of the light source substrate 120A along the Z direction is larger than the length (thickness) of the light source substrate 120 along the Z direction.

[0135] As shown in Figures 8A and 8B, a light source substrate 120A, on which light sources 122 are arranged in a single row, is mounted on a substrate holding member 130A in the straight tube lamp 100A.

[0136] The light source substrate 120A is a flat plate extending in the longitudinal direction. The light source 122 is placed on the light source substrate 120A. The light source substrate 120A is mounted on the substrate holding member 130A.

[0137] The light source substrate 120A has a first main surface 120a, a second main surface 120b, a side surface 120c1, and a side surface 120c2. The length (width) of the first main surface 120a and the second main surface 120b of the light source substrate 120A along the X direction is smaller than the length (width) of the first main surface 120a and the second main surface 120b of the light source substrate 120 along the X direction. Also, the length (thickness) of the side surfaces 120c1 and 120c2 of the light source substrate 120A along the Z direction is larger than the length (thickness) of the side surfaces 120c1 and 120c2 of the light source substrate 120 along the Z direction.

[0138] The main surface 120a of the light source substrate 120A is in contact with the projection 134 of the substrate holding member 130A. More precisely, the main surface 120a of the light source substrate 120A may not be in contact with the projection 134 of the substrate holding member 130A, and there may be a gap between them.

[0139] The main surface 120b of the light source substrate 120A is in contact with the first opposing surface 130s1 of the stepped portion 130s of the substrate holding member 130A. More precisely, the main surface 120b of the light source substrate 120A may not be in contact with the first opposing surface 130s1 of the stepped portion 130s of the substrate holding member 130A, and there may be a gap between them.

[0140] The side surface 120c1 of the light source substrate 120A faces the intersecting surface 130s2 of the stepped portion 130s in the substrate holding member 130A. The side surface 120c1 of the light source substrate 120A may also be in contact with the intersecting surface 130s2 of the stepped portion 130s in the substrate holding member 130A.

[0141] Similarly, the side surface 120c2 of the light source substrate 120A faces the intersecting surface 130s2 of the stepped portion 130s in the substrate holding member 130A. The side surface 120c2 of the light source substrate 120A may also be in contact with the intersecting surface 130s2 of the stepped portion 130s in the substrate holding member 130A.

[0142] Thus, the substrate holding member 130A has a mounting surface 130c that contacts or faces the light source substrate 120A when the light source substrate 120A is mounted on the substrate holding member 130A. Here, the substrate holding member 130A contacts the light source substrate 120A on three surfaces. Specifically, the substrate holding member 130A contacts the light source substrate 120A with the -Z direction side surface (first opposing surface 130s1) of the stepped portion 130s in the reference portion 132, the +X direction side and -Z direction side surface of the projection portion 134, and the -X direction side and -Z direction side surface of the projection portion 134.

[0143] Therefore, the mounting surface 130c on the substrate holding member 130A to which the light source substrate 120A is mounted is the -Z direction side of the stepped portion 130s of the reference portion 132 (first opposing surface 130s1), the +X direction side and -Z direction side of the projection portion 134, and the -X direction side and -Z direction side of the projection portion 134.

[0144] Thus, in the stepped portions 130s on the +X and -X sides of the substrate holding member 130A, the first opposing surface 130s1 is located on the -Z side of the reference portion 132 and contacts the light source substrate 120A when the light source substrate 120 is mounted on the substrate holding member 130A. Therefore, the stepped portions 130s in the substrate holding member 130A are connected to the mounting surface 130c on the substrate holding member 130A to which the light source substrate 120A is mounted.

[0145] In the straight tube lamp 100A of this embodiment, the substrate holding member 130A can appropriately mount either the light source substrate 120 or the light source substrate 120A due to the stepped portion 130s. Specifically, the light source substrate 120 is mounted on the second opposing surface 130s3 of the stepped portion 130s of the substrate holding member 130A, and the light source substrate 120A is mounted on the first opposing surface 130s1 of the stepped portion 130s of the substrate holding member 130A. Therefore, in the straight tube lamp 100A of this embodiment, the same substrate holding member 130A can mount light source substrates 120 and 120A, which have different widths and thicknesses.

[0146] According to the straight tube lamp 100A of this embodiment, both the light source substrate 120 and the light source substrate 120A can be properly mounted using a single type of substrate holding member 130A. Therefore, there is no need to manufacture different substrate holding members depending on the type of light source substrate, and the increase in the number of parts can be suppressed.

[0147] Furthermore, in the straight tube lamp 100A of this embodiment, the position of the main surface 120a of the light source substrate 120A relative to the inclined surface 134s of the projection 134 is almost the same as the position of the main surface 120a of the light source substrate 120 relative to the inclined surface 134s of the projection 134. Therefore, it is possible to easily design the orientation direction of the light emitted from the light source 122. In addition, the shadow cast by the light emitted from the light source 122 hitting the projection 134 of the substrate holding member 130A is suppressed.

[0148] In the straight tube lamp 100A of this embodiment, the stepped portion 130s is provided on the projection portion 134. This allows the main surface 120a to be mounted in approximately the same position even if the light source substrates 120 and 120A are different, making it easier to design the orientation direction of the light emitted from the light source 122.

[0149] In the straight tube lamp 100A shown in Figure 6, the main surface 120b of the light source substrate 120 is separated from the first opposing surface 130s1 of the stepped portion 130s in the substrate holding member 130, and the heat generated in the light source substrate 120 is not directly transferred from the main surface 120b of the light source substrate 120 to the first opposing surface 130s of the stepped portion 130s in the substrate holding member 130. However, this embodiment is not limited to this. A member that fills the gap between the main surface 120b of the light source substrate 120 and the first opposing surface 130s1 of the stepped portion 130s in the substrate holding member 130 may be attached to the main surface 120b of the light source substrate 120. Furthermore, it is preferable that the member that fills the gap between the main surface 120b of the light source substrate 120 and the first opposing surface 130s1 of the stepped portion 130s in the substrate holding member 130 is a heat dissipation member.

[0150] Furthermore, in the above description with reference to Figures 1 to 8B, the light source substrates 120 and 120A were held by integrally formed substrate holding members 130 and 130A, but this embodiment is not limited to this. The substrate holding members 130 and 130A that hold the light source substrates 120 and 120A may be composed of multiple members.

[0151] [Third Embodiment] Next, the straight tube lamp 100B of this embodiment will be described with reference to Figures 9A to 10. Figure 9A is a schematic cross-sectional view of the straight tube lamp 100B of this embodiment. Figure 9B is a schematic cross-sectional view of the substrate holding member 130B in the straight tube lamp 100B of this embodiment. Figure 9C is a schematic cross-sectional view of the light source substrate 120 and the substrate holding member 130B in the straight tube lamp 100B of this embodiment. Note that the straight tube lamp 100B shown in Figures 9A to 10 has the same configuration as the straight tube lamp 100 described above with reference to Figures 3A, 4A, 4B and 5A, except that the substrate holding member 130B is composed of a support member 130t and a covering member 130u, and redundant explanations will be omitted to avoid redundancy.

[0152] As shown in Figures 9A and 9B, in the straight tube lamp 100B, the substrate holding member 130B has a support member 130t and a covering member 130u. The support member 130t is located on the +Z side of the covering member 130u. Here, the substrate holding member 130B is composed of the support member 130t and the covering member 130u.

[0153] The support member 130t is in the shape of a thin plate. The support member 130t has a main surface that extends in the XY plane. The support member 130t supports the light source substrate 120. The support member 130t is in contact with the second main surface 120b of the light source substrate 120. The support member 130t constitutes the reference portion 132 of the substrate holding member 130B. For example, the support member 130t is formed from aluminum. Typically, the support member 130t is formed by extrusion molding.

[0154] The support member 130t is composed of a heat dissipation member. The support member 130t functions as a so-called heat sink. In this case, the thermal conductivity of the support member 130t is higher than that of the light source substrate 120. Furthermore, the thermal conductivity of the support member 130t is higher than that of the cylindrical member 110.

[0155] The covering member 130u covers the light source substrate 120. The covering member 130u covers the side surfaces 120c1, 120c2 and the edges of the main surface 120a of the light source substrate 120. The covering member 130u constitutes the projection 134 and the connecting portion 136 of the substrate holding member 130B. Here, a stepped portion 130s is provided on the projection 134 of the substrate holding member 130B. The covering member 130u may also constitute a part of the reference portion 132 of the substrate holding member 130B. For example, the covering member 130u is formed from resin. Typically, the covering member 130u is formed by extrusion molding.

[0156] The straight tube lamp 100B has a light source substrate 120 in which light sources 122 are arranged in two rows, which is attached to a substrate holding member 130B.

[0157] As shown in Figures 9A and 9C, the light source substrate 120 is mounted on the support member 130t and the covering member 130u of the substrate holding member 130B. When the light source substrate 120 is mounted on the substrate holding member 130B, the main surface 120a of the light source substrate 120 contacts the second opposing surface 130s3 of the stepped portion 130s in the substrate holding member 130B. More precisely, the main surface 120a of the light source substrate 120 does not contact the second opposing surface 130s3 of the stepped portion 130s in the substrate holding member 130B, and there may be a gap between the two surfaces.

[0158] When the light source substrate 120 is mounted on the substrate holding member 130B, the main surface 120b of the light source substrate 120 contacts the reference portion 132 of the substrate holding member 130B. More precisely, the main surface 120b of the light source substrate 120 does not contact the reference portion 132 of the substrate holding member 130B, and there may be a gap between the two surfaces facing each other.

[0159] When the light source substrate 120 is mounted on the substrate holding member 130B, the side surface 120c1 of the light source substrate 120 faces the inner wall 136w of the connection portion 136 of the substrate holding member 130B. The side surface 120c1 of the light source substrate 120 may also be in contact with the inner wall 136w of the connection portion 136 of the substrate holding member 130B.

[0160] Similarly, when the light source substrate 120 is mounted on the substrate holding member 130B, the side surface 120c2 of the light source substrate 120 faces the inner wall 136w of the connection portion 136 of the substrate holding member 130B. The side surface 120c2 of the light source substrate 120 may also be in contact with the inner wall 136w of the connection portion 136 of the substrate holding member 130B.

[0161] Thus, the substrate holding member 130B has a mounting surface 130c that contacts or faces the light source substrate 120 when the light source substrate 120 is mounted on the substrate holding member 130B. Here, the substrate holding member 130B contacts the light source substrate 120 on three surfaces. Specifically, the substrate holding member 130B contacts the light source substrate 120 with the +Z direction surface of the stepped portion 130s in the reference portion 132, the +X direction and -Z direction surface of the stepped portion 130s in the projection portion 134 (second opposing surface 130s3), and the -X direction and -Z direction surface of the projection portion 134 (second opposing surface 130s3).

[0162] Therefore, the mounting surface 130c on the substrate holding member 130B to which the light source substrate 120 is attached consists of the surface on the +Z direction side of the reference portion 132, the surface on the +X direction and -Z direction side of the stepped portion 130s of the projection 134 (second opposing surface 130s3), and the surface on the -X direction and -Z direction side of the stepped portion 130s of the projection 134 (second opposing surface 130s3).

[0163] In the stepped portion 130s on the +X direction side of the substrate holding member 130B, the second opposing surface 130s3 is located on the +X direction and -Z direction side of the projection 134, and contacts the light source substrate 120 when the light source substrate 120 is mounted on the substrate holding member 130B. Therefore, the stepped portion 130s in the substrate holding member 130B is connected to the mounting surface 130c on the substrate holding member 130B where the light source substrate 120 is mounted. Also, in the stepped portion 130s on the -X direction side of the substrate holding member 130B, the second opposing surface 130s3 is located on the -X direction and -Z direction side of the projection 134, and contacts the light source substrate 120 when the light source substrate 120 is mounted on the substrate holding member 130B. Therefore, the stepped portion 130s in the substrate holding member 130B is connected to the mounting surface 130c on the substrate holding member 130B where the light source substrate 120 is mounted.

[0164] Next, the straight tube lamp 100B of this embodiment will be described with reference to Figures 9A to 10. Figure 10 is a schematic cross-sectional view of the straight tube lamp 100B of this embodiment. The straight tube lamp 100B shown in Figure 10 has the same configuration as the straight tube lamp 100B described above with reference to Figure 9A, except that a light source substrate 120A, which is different from the light source substrate 120, is mounted on the substrate holding member 130B. To avoid redundancy, redundant explanations will be omitted.

[0165] As shown in Figure 10, the straight tube lamp 100B comprises a cylindrical member 110, a light source substrate 120A, and a substrate holding member 130B. In the straight tube lamp 100B, light sources 122 are arranged in a single row on the light source substrate 120A. The light source substrate 120A and the substrate holding member 130B are placed inside the cylindrical member 110. The light source substrate 120A is mounted on the substrate holding member 130B.

[0166] As can be seen from comparing Figure 9A and Figure 10, in Figure 9A, the light source substrate 120 is mounted on the substrate holding member 130B, whereas in Figure 10, the light source substrate 120A is mounted on the substrate holding member 130B. The length (width) of the light source substrate 120A along the X direction is smaller than the length (width) of the light source substrate 120 along the X direction. Also, the length (thickness) of the light source substrate 120A along the Z direction is larger than the length (thickness) of the light source substrate 120 along the Z direction.

[0167] As shown in Figure 10, the light source substrate 120A is attached to the support member 130t and the covering member 130u of the substrate holding member 130B.

[0168] In detail, the main surface 120a of the light source substrate 120A is in contact with the first opposing surface 130s1 of the stepped portion 130s of the substrate holding member 130B. More precisely, the main surface 120a of the light source substrate 120A may not be in contact with the first opposing surface 130s1 of the stepped portion 130s of the substrate holding member 130B, and there may be a gap between them.

[0169] The main surface 120b of the light source substrate 120A is in contact with the reference portion 132 of the substrate holding member 130B. More precisely, the main surface 120b of the light source substrate 120A may not be in contact with the reference portion 132 of the substrate holding member 130B, and there may be a gap between them.

[0170] The side surface 120c1 of the light source substrate 120A faces the intersecting surface 130s2 of the stepped portion 130s in the substrate holding member 130B. The side surface 120c1 of the light source substrate 120A may also be in contact with the intersecting surface 130s2 of the stepped portion 130s in the substrate holding member 130B.

[0171] Similarly, the side surface 120c2 of the light source substrate 120A faces the intersecting surface 130s2 of the stepped portion 130s in the substrate holding member 130B. The side surface 120c2 of the light source substrate 120A may also be in contact with the intersecting surface 130s2 of the stepped portion 130s in the substrate holding member 130B.

[0172] Thus, the substrate holding member 130B has a mounting surface 130c on which the light source substrate 120A is mounted. The substrate holding member 130B contacts the light source substrate 120 on three surfaces. Specifically, the substrate holding member 130B contacts the light source substrate 120 with the surface of the reference portion 132 on the +Z direction side, the surface of the stepped portion 130s of the projection 134 on the +X direction and +Z direction side (first opposing surface 130s1), and the surface of the stepped portion 130s of the projection 134 on the -X direction and +Z direction side (first opposing surface 130s1).

[0173] Therefore, the mounting surface 130c on the substrate holding member 130B to which the light source substrate 120A is mounted consists of the surface on the +Z direction side of the reference portion 132, the surface on the +X direction and +Z direction side of the stepped portion 130s of the projection portion 134 (first opposing surface 130s1), and the surface on the -X direction and +Z direction side of the stepped portion 130s of the projection portion 134 (first opposing surface 130s1).

[0174] Thus, at the stepped portion 130s on the +X direction side of the substrate holding member 130B, the first opposing surface 130s1 is located on the +X and +Z direction side of the projection 134 and contacts the light source substrate 120A when the light source substrate 120A is mounted on the substrate holding member 130B. Therefore, the stepped portion 130s of the substrate holding member 130B is connected to the mounting surface 130c on the substrate holding member 130B to which the light source substrate 120A is mounted. Furthermore, at the stepped portion 130s on the -X direction side of the substrate holding member 130B, the first opposing surface 130s1 is located on the -X and +Z direction side of the projection 134 and contacts the light source substrate 120A when the light source substrate 120A is mounted on the substrate holding member 130B. Therefore, the stepped portion 130s in the substrate holding member 130B is connected to the mounting surface 130c on the substrate holding member 130B where the light source substrate 120A is mounted.

[0175] In the straight tube lamp 100B of this embodiment, the substrate holding member 130B can appropriately mount either the light source substrate 120 or the light source substrate 120A due to the stepped portion 130s. Specifically, the light source substrate 120 can be mounted on the second opposing surface 130s3 of the stepped portion 130s in the substrate holding member 130B, and the light source substrate 120A can be mounted on the first opposing surface 130s1 of the stepped portion 130s in the substrate holding member 130B. Therefore, in the straight tube lamp 100B of this embodiment, the same substrate holding member 130B can be used to mount light source substrates 120 and 120A, which have different widths and thicknesses.

[0176] According to the straight tube lamp 100B of this embodiment, both the light source substrate 120 and the light source substrate 120A can be properly mounted using a single type of substrate holding member 130BB. Therefore, there is no need to prepare different substrate holding members depending on the type of light source substrate, and the increase in the number of parts can be suppressed.

[0177] The support member 130t is inserted into the covering member 130u. The support member 130t may be bonded to the covering member 130u with an adhesive, or it may be fastened to the covering member 130u with a fastener.

[0178] This disclosure is not limited to the embodiments described above, and can be implemented in various forms without departing from its essence. The drawings schematically show each component for ease of understanding, and the thickness, length, number, etc. of each component shown may differ from the actual dimensions due to the convenience of drawing creation. Furthermore, the materials, shapes, dimensions, etc. of each component shown in the embodiments described above are examples and are not particularly limiting, and various modifications are possible without substantially departing from the effects of this disclosure.

[0179] For example, in the straight tube lamps 100, 100A, and 100B shown in Figures 3A to 10, the substrate holding members 130, 130A, and 130B are provided with one stepped portion 130s, but this embodiment is not limited to this. The substrate holding members 130, 130A, and 130B may be provided with two or more stepped portions. [Industrial applicability]

[0180] According to this disclosure, in a straight tube lamp, light source substrates of different widths can be mounted using the same substrate holding member. [Explanation of Symbols]

[0181] 100 straight tube lamps 110 Cylindrical member 120 Light source substrate 122 Light source 130 Substrate holding member 130t support member 130u covering member 130s step 130s1 1st facing surface 130s2 Intersecting surface 130s3 Second opposing surface 132 Reference section 134 Protrusion 136 Connection part

Claims

1. A cylindrical member extending in the longitudinal direction, A light source substrate on which light sources are arranged, A substrate holding member is disposed inside the cylindrical member and holds the light source substrate. Equipped with, The substrate holding member has a stepped portion connected to the mounting surface on which the light source substrate is attached, and is a straight tube lamp.

2. The straight tube lamp according to claim 1, wherein the substrate holding member includes a heat dissipation member that dissipates heat generated in the light source substrate.

3. The aforementioned light source substrate is The first main surface on which the light source is arranged, A second main surface different from the first main surface and It has, The substrate holding member is A projection facing the first main surface of the light source substrate, A reference portion facing the second main surface of the light source substrate and A connecting portion that connects the reference portion and the projection portion. It has, The stepped portion is provided on at least one of the projection portion and the reference portion, as described in claim 1.

4. The stepped portion is provided on the protruding portion, as described in claim 3, for the straight tube lamp.

5. The aforementioned stepped portion is A first opposing surface facing the reference portion, Intersecting surfaces that intersect with the first opposing surface, A second opposing surface that faces the reference portion, intersects with the intersecting surface, and is located closer to the connecting portion than the first opposing surface. A straight tube lamp according to claim 4, having the following features.

6. The straight tube lamp according to claim 5, wherein the length of the first opposing surface is smaller than the length of the second opposing surface in the width direction perpendicular to the longitudinal direction and the normal direction of the reference portion, respectively.

7. The stepped portion is provided on the reference portion, as described in claim 3, for the straight tube lamp.

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