JP4166739B2 - lighting equipment - Google Patents

Description

  The present invention relates to a lighting fixture such as an explosion-proof straight tube fluorescent lamp lighting device.

  A conventional explosion-proof straight tube fluorescent lamp illuminating device includes a socket holder formed in a cylindrical body having an electrical contact as shown in Patent Document 1, and a straight tube fluorescent lamp fitted into the socket holder and electrically connected thereto. And a socket having a terminal that can be pressed into contact with the electrical contact.

That is, FIG. 18 is a cross-sectional view around the butt-side socket of the conventional example, and FIG. 19 is a cross-sectional view around the insertion-side socket of the conventional example. 18 and 19, 50 is a butt socket, 51 is a plug-in socket, 52 is a spring terminal, 53 is a socket holder, 54 socket holder terminal, 55 is a cap, and 56 is a straight tube fluorescent lamp. The butted socket 50 is connected by contacting a lamp pin at one end of the straight tube fluorescent lamp 56, and the plug-in socket 51 is connected by holding the lamp pin at the other end of the straight tube fluorescent lamp 56. In addition, since the configuration in which the butt socket 50 and the plug-in socket 51 are fitted and electrically connected to the socket holder 53 is the same, only one socket 51 will be described. That is, by opening the cap 55 and fitting the socket 51 into the socket holder 53, the spring terminal 52 and the socket holder terminal 54 are brought into contact with each other to realize electrical connection. At this time, as shown in FIGS. 20A and 20B, when the spring terminal 52 is connected to the socket holder terminal 54, the dimension a bends.
JP-A-11-53930

  In the above-mentioned conventional lighting fixture, the material of the socket body constituting the outer shell of the socket is a thermosetting resin such as melamine phenol. As a feature of this thermosetting resin, heat shrinkage occurs after molding in a high temperature atmosphere. appear. 21 (a) and 21 (b) are cross-sectional views in which the cut surface of the socket in the conventional example is different, and FIGS. 22 (a) and 22 (b) are cross-sectional views in which the cut surface of the socket is thermally contracted. . As shown in FIG. 21, in the initial state, the socket main body 51 a has projections 57 formed on the bottom and both sides abutting against the inner peripheral surface of the socket holder 53. At this time, the spring terminal 52 is pressed by the socket holder terminal 54, and the protrusion dimension is c. As shown in FIG. 22, when the socket main body 51 a is thermally contracted, the socket main body 51 a is brought into a shifted state, and only the bottom protrusion portion 57 contacts the inner peripheral surface of the socket holder 53. At this time, the projecting dimension of the spring terminal 52 becomes d, the amount of deflection of the spring terminal 52 corresponding to dc decreases, and the contact pressure decreases. FIG. 23 is a state diagram showing a change in the thermal contraction state from the initial state.

  As described above, the connection of the socket side terminal to the socket holder side terminal is not a screw connection or a quick connection, but a pressing contact, and the contact pressure is reduced as the socket body is thermally contracted. May cause fever. Further, since the socket holder and the socket main body were in sliding contact with each other at the bottom of the socket, they tend to be unstable with respect to the movement in the rotational direction, and the electrical connection state was not stable.

  Accordingly, an object of the present invention is to provide a lighting fixture capable of obtaining a stable electrical connection state between a socket side terminal and a socket holder side terminal.

  In order to solve the above-mentioned problem, a lighting fixture according to claim 1 of the present invention is a pair of socket holders formed in a cylindrical body having an electrical contact on an inner wall, and a pair that can be fitted into the socket holder and pressed against the electrical contact. In a lighting fixture comprising a socket having a terminal of the outer periphery and a straight fluorescent lamp electrically connected to an end of the socket, the electrical contacts are respectively connected to the socket holder and the fitting portion of the socket. Both sides of a center line passing through the axis of the socket holder from the center between the pair of terminals on a plane perpendicular to the axis of the socket holder, the substantially flat contact portion that receives a pressing force when the is pressed against the pair of terminals It provided so that it might be located in.

  The lighting fixture according to claim 2 is the lighting fixture according to claim 1, wherein the socket main body fitted to the socket holder of the socket is made of a material having a larger thermal contraction than the socket holder.

  The lighting fixture according to claim 3 is line symmetric with respect to a center line passing through the axis of the socket holder in a contact pressing direction of the socket holder in a plane perpendicular to the axis of the socket holder in the lighting fixture according to claim 1 or 2. It was formed so as to be inclined.

  The lighting fixture according to claim 4 is the lighting fixture according to claim 3, wherein the substantially flat contact portion is inclined in a direction extending from the socket center toward the side opposite to the contact side.

  The lighting fixture according to claim 5 is the lighting fixture according to claim 1 or 2, wherein the fitting portion of the socket is provided so as to sandwich a portion on the socket holder side around the electrical contact, and the substantially flat contact portion Was provided on a substantially extended line outside the straight contact portion connecting the socket center and the contact portion of the electrical contact.

  The lighting fixture according to claim 6 is the lighting fixture according to claim 1, wherein the socket has a structure in which a pressing force is always applied to the lamp side, and the substantially flat contact portion is in an axial direction of the straight fluorescent lamp. An upward taper was provided toward the contact portion side of the electrical contact toward the lamp side.

  According to the lighting apparatus of the first aspect of the present invention, each of the socket holder and the fitting portion of the socket is provided with the substantially flat contact portion that receives the pressing force when the electrical contact is pressed against the pair of terminals. Therefore, the surfaces are in contact with each other at the time of fitting, and the movement of the socket in the socket holder in the rotation direction can be largely restricted by this surface contact. Thereby, the electrical connection state between the electrical contact on the socket holder side and the terminal on the socket side is very stable. Since the finish of the portion other than the fitting surface may be rough, the effect is particularly great when the socket holder is made of die casting.

  In addition, since the position of the substantially flat contact portion is within the range on the center line passing through the axis of the socket holder from the center between the pair of terminals (non-bottom portion), the distance between the pair of terminals and the substantially flat contact portion However, since the distance between the pair of terminals is smaller than the distance between the socket bottoms, the change in the contact pressure between the terminals when the socket body is thermally contracted is smaller than when the contact is made at the socket bottom. Furthermore, the outer shape of the conventional socket body has been made substantially circular to match the shape of the inner peripheral surface of the socket holder in order to bring the socket bottom portion into contact with the socket holder, but this is no longer necessary. It can be made compact, saving materials, and improving aesthetics.

  Further, the substantially flat contact portions are located on both sides of the center line passing through the socket holder axis from the center between the pair of terminals on the plane orthogonal to the socket holder axis, so that the pressing forces on both sides are greatly different. Even if a force is applied in the direction in which the socket rotates, the rotating force is easily received. For this reason, the electrical connection state is stable as compared with the conventional one-point contact at the bottom of the socket.

  According to a second aspect of the present invention, in the luminaire according to the first aspect, the socket main body fitted to the socket holder of the socket is particularly effective because it is formed of a material having a larger thermal shrinkage than the socket holder.

  In claim 3, since the substantially flat contact portion is formed so as to incline in line symmetry with respect to the center line passing through the socket holder axis in the contact pressing direction of the socket holder on the surface orthogonal to the axis of the socket holder. Even if the position of the socket is shifted, the socket and the socket holder can be correctly aligned easily by sliding along the inclined surface.

  According to the fourth aspect of the present invention, the substantially flat contact portion is inclined in a direction extending from the socket center toward the side opposite to the contact side. Therefore, when the socket body is thermally contracted, the substantially flat contact portion is inclined on the socket side. The surface is moved up to the terminal side by thermal contraction in a direction in which the inclined surface on the socket holder side is sandwiched from both sides. In this case, since the contact pressure is higher than that in a configuration other than that, the reliability is improved.

  According to a fifth aspect of the present invention, the socket fitting portion is provided so as to sandwich the portion on the socket holder side around the electrical contact, and the substantially flat contact portion is outside the linear contact portion connecting the socket center and the contact portion of the electrical contact. Since the substantially flat contact portion is located on the upper side of the terminal, when the socket body is thermally contracted, the terminal is drawn to the electrical contact side. For this reason, since a contact pressure becomes high compared with the case where it is not so, reliability improves.

  According to a sixth aspect of the present invention, the socket has a structure in which a pressing force is always applied to the lamp side, and the substantially flat contact portion is directed upward toward the contact portion side of the electric contact toward the lamp side in the axial direction of the straight tube fluorescent lamp. Therefore, when the socket body is thermally contracted, the socket is pushed out to the lamp side, and the pressing force to the lamp side is higher than the contact pressure of the terminal on the socket side, so that the socket is tapered in the axial direction. Move along. At this time, since the taper is in the upward direction, the socket moves up to the terminal side. For this reason, since a contact pressure becomes high compared with the structure which is not so, reliability improves.

  A first embodiment of the present invention will be described with reference to FIGS. FIG. 1A is a front view of a plug-in type socket in the lighting fixture of the first embodiment of the present invention, FIG. 1B is a left side view, FIG. 1C is a right side cross-sectional view, and FIG. e) is a partially broken rear view, FIG. 2 is a perspective view of the plug-in socket, FIG. 3A is a front view of the explosion-proof lighting fixture of the embodiment of the present invention, and FIG.

  As shown in FIG. 3, the appliance body 1 includes a cylinder 2 that holds a straight tube fluorescent lamp inside, a guard 3 that protects the cylinder 2, a reflector 4, a terminal plate 5, and socket holders that are disposed at both ends of the cylinder 2. 6 etc. are installed. The socket holder 6 is formed in a cylindrical body having socket holder terminals (electrical contacts) on the inner wall. A socket for electrically connecting the lamp to the socket holder 6 slides and is accommodated in the socket holder 6. In addition, a straight tube fluorescent lamp is electrically connected to the end of the socket, and the lamp can be replaced from one end of the socket holder 6 that can be opened and closed. In this case, a plug-in socket is disposed in the socket holder 6 on the lamp insertion side of the cylinder 2, and a butting socket is disposed in the socket holder 6 on the opposite side to the lamp insertion side.

  As shown in FIGS. 1 and 2, the plug-in socket 7 is fitted to the socket holder 6 and has a socket body 8 made of a thermosetting resin such as melamine phenol having a larger thermal contraction than the socket holder 6, and the socket holder. A pair of spring terminals 9 that can be pressed against the terminals are provided. A lamp pin insertion hole 10 is provided on the lamp contact surface of the socket body 8, and fitting portions 11 project from both side surfaces. The fitting portion 11 has a substantially flat contact portion 11a formed with an upward taper toward the lamp contact surface, and is inclined to the lamp contact surface side from the substantially flat contact portion 11a to guide when the socket is inserted. And a guide portion 11b. The substantially flat contact portion 11a may not have a taper. The socket body 8 has a fixing portion 12 for the spring terminal 9 and an opening 13 for exposing the spring terminal 9 to the outside. The spring terminal 9 is in the range of a space formed by connecting the tops of the socket bodies 8 on both sides of the spring terminal 9 in a state of being arranged in the opening 13. Further, a plate cover 15 is screwed to the back surface of the socket main body 8, and a knob portion 14 is projected from the plate cover 15.

  The spring terminal 9 is made of a spring material having conductivity, and has a long convex portion 17 that comes into contact with the socket holder terminal. In this case, it is composed of an upper part and a lower part that are elastically deformed, and is integrally formed with a mounting plate 18 and a contact plate 19 that sandwiches the lamp pin. The attachment portion 18 is fixed to the fixing portion 12 of the socket body 8 by a screw 20 inserted through the hole. At this time, the tip of the spring terminal 9 is locked to the socket body 8.

  4A is a front view of a butt socket in the lighting fixture of the first embodiment of the present invention, FIG. 4B is a left side view, FIG. 4C is a right side cross-sectional view, and FIG. e) is a rear view, and FIG. 5 is a perspective view of the butted socket. Note that differences from the plug-in socket will be mainly described, and the same portions are denoted by the same reference numerals and description thereof will be omitted.

  As shown in FIGS. 4 and 5, the butt-type socket 22 is fitted into the socket holder 6 and has a socket main body 23 made of a thermosetting resin such as melamine phenol and a pair of springs that has a larger thermal contraction than the socket holder 6. And a terminal 24.

  The socket body 23 is provided with a guide surface 10a for the lamp pin around the lamp pin insertion hole 10, and does not have a plate cover or a knob portion. The spring terminal 24 is composed of an upper portion having a convex portion 17 and a lower portion, and is integrally formed with a connecting portion 25 on which the mounting portion 18 and the lamp pin abut.

  6 (a) and 6 (b) are cross-sectional views with different cut surfaces of the socket holder in the lighting fixture of the first embodiment of the present invention.

  As shown in FIG. 6, the socket holder 6 includes a socket holder main body 27 and a terminal unit 28. The socket holder main body 27 has a cylindrical shape into which the socket main body 8 or 23 is inserted, and an opening 29 for attaching the terminal unit 28 is formed. The terminal unit 28 is made of a thermosetting resin such as melamine phenol, and a socket holder terminal 35 is insert-molded on the bottom surface of a recess 34 made of an insulator. Further, a rib 30 and a partitioning portion 31 on which the fitting portion 11 slides project from the inner peripheral surface of the socket holder main body 27. The rib 30 has a substantially flat contact portion 30a having an upward taper toward the lamp side C, and a guide portion that is inclined more than the substantially flat contact portion 30a on the opposite side of the lamp and serves as a guide when the socket is inserted. 30b. The substantially flat contact portion 30a may not be tapered. The substantially flat contact portions 11a and 30a are located at two locations on both sides of the center line T passing through the axis of the socket holder 6 from the center between the pair of spring terminals 9 on the surface orthogonal to the axis of the socket holder 6. A pressing force is received when 35 is in press contact with the spring terminal 9. A thread groove 32 for screwing an end cap (not shown) is provided at one end, and a mounting portion 33 for the cylinder 2 is provided at the other end.

  Next, the heat shrinkage of the socket and its built-in state will be described. FIGS. 7A and 7B are explanatory diagrams of the heat-shrinked state of the socket according to the first embodiment of the present invention, and FIGS. Cross-sectional views with different surfaces, and FIGS. 9A and 9B are cross-sectional views with different cut surfaces in the heat-shrinkable state. Although the figure shows a plug-in socket, the same applies to a butt socket.

  Since the position of the substantially flat contact portion 11a is within the range (the non-bottom portion) on the center line T passing through the axis of the socket holder 6 from the center between the pair of spring terminals 9, the substantially flat contact is made from the spring terminal 9. The distance between the portions 11a is smaller than the distance between the spring terminal 9 and the socket bottom. For this reason, when the socket body 8 is thermally contracted, the contraction origin A is located as shown in FIG. 7B when the contact is made by the substantially flat contact portion 11a as in this embodiment, and the heat contraction allowance is located. f becomes smaller. On the other hand, when the contact is made at the bottom of the socket, the contraction origin A is located as shown in FIG. As a result, in this embodiment, the change in the contact pressure between the terminals is smaller than that in the case where the contact is made at the bottom of the socket.

  Further, at the time of assembly, as shown in FIG. 8, the socket 7 is inserted from one end of the socket holder 6 with the fitting portion 11 positioned by the rib 30. The spring terminal 9 is pressed and elastically deformed by the terminal unit 28, the convex portion 17 is inserted into the concave portion 34, the socket holder terminal 35 and the spring terminal 9 are in sliding contact, and the socket 7 and the socket holder 6 are electrically connected. Connected to. At this time, there is a gap 36 between the bottom of the socket 7 and the socket holder 6. As shown in FIG. 9, when the socket body 8 is thermally contracted, the socket body 8 is contracted around the contraction origin A. However, as shown in FIG. Is only slightly elastic.

  Further, the outer shape of the conventional socket main body is substantially circular in accordance with the shape of the inner peripheral surface of the socket holder in order to bring the bottom of the socket into contact with the socket holder. In this way, the socket bottom can be made much more compact, saving material and improving aesthetics. Reference numeral 37 denotes an unnecessary portion of the socket body. Moreover, as shown in FIG. 11, you may form the lower part 11c in the fitting part 11 so that the rib 30 may be inserted | pinched from the up-and-down both sides.

  As described above, according to the present embodiment, when the socket is fitted, the surfaces of the substantially flat contact portions 11a and 30a are in contact with each other, and the movement of the sockets 7 and 22 in the rotation direction within the socket holder 6 is the surface contact. Can be greatly regulated. Thereby, the electrical connection state of the socket holder terminal 35 and the spring terminal 9 is very stable. Since the finish of the portion other than the fitting surface may be rough, the effect is particularly great when the socket holder 6 is made of die casting.

  Further, the substantially flat contact portions 11a and 30a are positioned at two locations on both sides of the center line T passing through the axis of the socket holder 6 from the center between the pair of spring terminals 9 on the plane orthogonal to the axis of the socket holder 6. Even if the pressing force at the two locations on the both sides is greatly different and a force is applied in the direction in which the sockets 7 and 22 rotate, the rotational force can be easily received. For this reason, the electrical connection state is stable as compared with the conventional one-point contact at the bottom of the socket.

  12 (a) and 12 (b) are explanatory views showing the state of the socket in the lighting fixture of the second embodiment of the present invention. The figure shows a plug-in socket, but a butt socket may be used.

  As shown in FIG. 12, in this embodiment, the shape of the fitting part 11 of the socket 7 and the rib 30 of the socket holder 6 differs in 1st Embodiment. That is, the substantially flat contact portion 11a of the fitting portion 11 and the substantially flat contact portion 30a of the rib 30 are not on the same plane, but on the surface perpendicular to the axis of the socket holder 6 in the contact pressing direction of the socket holder 6 in the socket holder. It is formed so as to incline symmetrically with respect to a center line T passing through the six axes. In this case, the substantially flat contact portions 11a and 30a have a reverse C shape with the inside facing downward. Even if the socket main body 8 is inserted in an inclined state in the socket holder 6 as shown in FIG. 12A, the reverse C shape of the substantially flat contact portion 30a of the socket holder 6 as shown in FIG. The substantially flat abutting portion 11a of the socket 7 is guided along and is in a normal state. Thus, even if the position of the socket body 8 is shifted, the socket body 8 and the socket holder 6 can be easily aligned correctly by sliding along the inclined surface.

  FIGS. 13A and 13B are explanatory views showing the state of the socket in the lighting fixture of the third embodiment of the present invention. The figure shows a plug-in socket, but a butt socket may be used.

  As shown in FIG. 13, in this embodiment, the position and shape of the fitting part 11 of the socket 7 and the rib 30 of the socket holder 6 differ in 1st Embodiment. That is, the fitting portions 11 are provided on both sides of the bottom portion of the socket main body 8, and the ribs 30 project from the bottom portion of the socket holder 6. Similarly to the second embodiment, the substantially flat contact portion 11a of the fitting portion 11 and the substantially flat contact portion 30a of the rib 30 are not on the same plane, but on the surface orthogonal to the axis of the socket holder 6. 6 is formed so as to be inclined symmetrically with respect to a center line T passing through the axis of the socket holder 6 in the contact pressing direction. The substantially flat contact portions 11a and 30a are inclined in a direction extending from the socket center toward the side opposite to the contact side. In this case, both side surfaces of the rib 30 are formed in a C shape to form a substantially flat contact portion 30a. As shown in FIG. 13A, the socket body 8 is inserted into the socket holder 6 and the substantially flat contact portions 11a and 30a are in contact with each other, between the fitting portion 11 and the bottom portion of the socket holder 6. A gap g is formed. When the socket body 8 is thermally contracted as shown in FIG. 13B, the socket body 8 is changed to a gap h, and the socket body 8 is pushed upward along the inclined surface of the substantially flat contact portion 30a by the amount h-g. As described above, when the socket body 8 is thermally contracted, the inclined surface on the socket 7 side in the substantially flat contact portions 11a and 30a is thermally contracted in the direction of sandwiching the inclined surface on the socket holder 6 side from both sides. It moves up to the 9th side. For comparison, FIGS. 14A and 14B show an initial state and a thermal contraction state when the rib 30 is not provided. In this case, since the position of the contact surface B of the socket main body 8 and the socket holder does not change due to heat shrinkage, the distance between the contacts increases by the amount of heat shrinkage.

  15 (a) and 15 (b) are explanatory views showing the state of the socket in the lighting fixture of the fourth embodiment of the present invention. The figure shows a plug-in socket, but a butt socket may be used.

  As shown in FIG. 15, in this embodiment, the position and shape of the fitting part 11 of the socket 7 and the rib 30 of the socket holder 6 differ in 1st Embodiment. That is, the fitting part 11 is provided on both sides of the upper part of the socket body 8 so as to sandwich the terminal unit 28 around the socket holder terminal 35, and the ribs 30 to be fitted to the terminal unit 28 protrude from the terminal unit 28. . Further, the substantially flat contact portion 11 a of the fitting portion 11 and the substantially flat contact portion 30 a of the rib 30 are provided on a substantially extended line outside the straight contact portion connecting the contact portion of the socket center and the socket holder terminal 35. ing. When the socket main body 8 is thermally contracted as shown in FIG. 15B from the state in which the socket main body 8 is inserted into the socket holder 6 as shown in FIG. 15A, it is directed toward the substantially flat contact portions 11a and 30a. The spring terminal 9 rises. As described above, the substantially flat contact portions 11a and 30a are positioned on the upper side of the spring terminal, so that when the socket body 8 is thermally contracted, the spring terminal 9 is drawn toward the socket holder terminal 35 side.

  16 (a) and 16 (b) are explanatory views showing a state when a socket is inserted in the lighting fixture of the fifth embodiment of the present invention, and FIG. 17 is an explanatory view of the socket inserted state. The figure shows a plug-in socket, but a butt socket may be used.

  As shown in FIG. 16, in this embodiment, the shape of the fitting part 11 of the socket 7 and the rib 30 of the socket holder 6 differs in 1st Embodiment. That is, the substantially flat contact portion 11a of the fitting portion 11 and the substantially flat contact portion 30a of the rib 30 rise to the contact portion side of the socket holder terminal 35 toward the lamp side C in the axial direction of the straight tube fluorescent lamp. A direction taper is provided. Further, as shown in FIG. 17, the socket 7 has a structure in which a pressing force is always applied to the lamp side C. In this case, a spring 38 capable of pressing the socket body 8 is attached to the inside of the holder cap that is screwed into the socket holder 6. Moreover, the fitting part 11 and the rib 30 have guide parts 11b and 30b which are inclined more than the substantially flat contact parts 11a and 30a and serve as a guide when the socket is inserted, as in the first embodiment. When the socket body 8 is inserted into the socket holder 6 as shown in FIGS. 16 (a) and 16 (b), the fitting portion 11 and the rib 30 are fitted onto the respective guide portions 11b and 30b. As shown in FIG. 17, the socket body 8 is pushed upward as it goes to the lamp side C. The socket body 8 is pressed against the lamp side C by the load of the spring 38. For this reason, when the socket body 8 is thermally contracted, the socket 7 is pushed out from the back portion to the lamp side C by the spring 38. Since the spring pressure of the spring 38 is higher than the contact pressure of the spring terminal 9 on the socket side, the socket body 8 moves along the taper in the axial direction. At this time, since the taper is in the upward direction, the socket body 8 moves up to the spring terminal 9 side. As described above, according to the third to fifth embodiments, since the contact pressure of the contact is increased, the reliability is improved.

(A) is a front view of the plug-in type socket in the lighting fixture of the embodiment of the present invention, (b) is a left side view, (c) is a right side cross-sectional view, (d) is a plan view, and (e) is a part of it. FIG. It is a perspective view of the insertion type socket in the embodiment of the present invention. (A) is a front view of the explosion-proof lighting fixture of embodiment of this invention, (b) is a side view. (A) is a front view of a butt socket in the lighting fixture of the embodiment of the present invention, (b) is a left side view, (c) is a right side sectional view, (d) is a plan view, and (e) is a rear view. It is. It is a perspective view of the butting type socket in the embodiment of the present invention. (A) (b) is sectional drawing from which the cut surface of the socket holder in the lighting fixture of embodiment of this invention differs. (A) (b) is explanatory drawing of the heat contraction state of the socket in the 1st Embodiment of this invention. (A) (b) is sectional drawing from which the cut surface of the socket incorporating state in the 1st Embodiment of this invention differs. (A) (b) is sectional drawing from which the cut surface of the heat contraction state differs. (A) is sectional drawing which shows the modification of the lighting fixture of the 1st Embodiment of this invention, (b) is the explanatory drawing. It is sectional drawing which shows another modification of the lighting fixture of embodiment of this invention. (A) (b) is explanatory drawing which shows the state of the socket in the lighting fixture of the 2nd Embodiment of this invention. (A) (b) is explanatory drawing which shows the state of the socket in the lighting fixture of the 3rd Embodiment of this invention. (A) (b) is explanatory drawing which shows the initial state in case there is no rib, and a heat contraction state. (A) (b) is explanatory drawing which shows the state of the socket in the lighting fixture of the 4th Embodiment of this invention. (A) (b) is explanatory drawing which shows the state at the time of inserting the socket in the lighting fixture of the 5th Embodiment of this invention. It is explanatory drawing of the socket insertion state of 5th Embodiment. It is sectional drawing of the butt side socket periphery of a prior art example. It is sectional drawing of the insertion side socket periphery of a prior art example. It is explanatory drawing of the connection state in a prior art example. (A) (b) is sectional drawing from which the cut surface of the socket incorporation state in a prior art example differs. (A) (b) is sectional drawing from which the cut surface in the state which the socket in the prior art example thermally contracted differs. It is a state figure which shows the change of the heat contraction state from the initial state in a prior art example.

Explanation of symbols

6 Socket holder 7 Plug-in socket 8 Socket body 9 Spring terminal 11 Fitting portion 11a Substantially flat contact portion 22 Butt type socket 23 Socket main body 24 Spring terminal 30 Rib 30a Substantially flat contact portion 35 Socket holder terminal

Claims (6)

  A socket holder formed in a cylindrical body having an electrical contact on the inner wall, a socket having a pair of terminals around the socket holder that can be fitted into the socket holder and press-contacted with the electrical contact, and electrically connected to an end of the socket In the lighting fixture provided with the straight tube fluorescent lamp, the substantially flat contact portion that receives the pressing force when the electrical contact presses and contacts the pair of terminals to each of the socket holder and the fitting portion of the socket Is provided so as to be located on both sides of a center line passing through the axis of the socket holder from the center between the pair of terminals on a plane orthogonal to the axis of the socket holder.   The lighting fixture according to claim 1, wherein the socket body fitted into the socket holder of the socket is formed of a material having a larger thermal shrinkage than the socket holder.   The substantially flat contact portion is formed so as to be inclined in line symmetry with respect to a center line passing through the axis of the socket holder in a contact pressing direction of the socket holder on a surface orthogonal to the axis of the socket holder. The luminaire described.   The lighting device according to claim 3, wherein the substantially flat contact portion is inclined in a direction extending from the center of the socket toward a side opposite to the contact side.   The fitting portion of the socket is provided so as to sandwich a portion on the socket holder side around the electrical contact, and the substantially flat contact portion is outside a linear contact portion connecting the socket center and the contact portion of the electrical contact. The lighting fixture of Claim 1 or 2 provided on the substantially extended line.   The socket has a structure in which a pressing force is always applied to the lamp side, and the substantially flat contact portion tapers upward toward the contact portion side of the electric contact toward the axial lamp side of the straight tube fluorescent lamp. The lighting fixture of Claim 1 which provided.

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