WO2013018924A1

WO2013018924A1 - Contact structure of lighting switch and indoor lighting lamp for vehicle

Info

Publication number: WO2013018924A1
Application number: PCT/JP2012/070134
Authority: WO
Inventors: Manabu Sakai
Original assignee: Yazaki Corporation
Priority date: 2011-08-01
Filing date: 2012-08-01
Publication date: 2013-02-07
Also published as: JP2013033608A

Abstract

A contact structure 1 of a lighting switch includes a bus bar 50 and an electrically conducting contact piece part 82 which serves to electrically conduct to each other two contacts of a plurality of contacts formed in the bus bar 50 in accordance with an operating mode of a light source 60 by a switch operation. In the contact structure 1 of the lighting switch, an end part 81a of the bus bar 50 is folded back so as to have a U shaped section. Thus, an end part folded back part 53 is formed which has one pair of opposed plate shaped parts 52 opposed to each other in a vertical direction. Thus, the bus bar 50 has a lower bus bar part 54 formed in the lower opposed plate shaped part 52 and an upper bus bar part 55 formed in the upper opposed plate shaped part 52. The electrically conducting contact piece part 82 has a bent form bent so as to suppress an extent in a longitudinal direction or a transverse direction, and includes a lower contact 84 which is allowed to come into contact with the lower bus bar part 54 and an upper contact 85 which is allowed to come into contact with the upper bus bar part 55.

Description

DESCRIPTION

CONTACT STRUCTURE OF LIGHTING SWITCH AND INDOOR LIGHTING LAMP FOR VEHICLE

Technical Field

The present invention relates to a contact structure of a lighting switch and an indoor lighting lamp for a vehicle in which the contact structure of the lighting switch is incorporated.

Background Art

Usually, for instance, as an indoor lighting lamp for a vehicle used for an indoor illumination for a vehicle, an indoor lighting lamp is proposed in which a plurality of light sources are provided and the plurality of light sources are selectively allowed to light by a switching operation by a switch (for instance, see PTL 1).

In the indoor lighting lamp for a vehicle disclosed in the patent literature 1 , each lighting part includes three terminals respectively connected to a first conductor, a third conductor and a fourth conductor of a wire harness, a light source electrically connected to the terminal connected to the first conductor and a switch which can select a first position where the terminal connected to the third conductor is electrically conducted to the light source or a second position where the terminal connected to the fourth conductor is electrically conducted to the light source. A mode changing switch includes two terminals respectively connected to a second conductor and the fourth conductor of the wire harness and a changing switch which can select a short state in which the terminal connected to the second conductor is electrically conducted to the terminal connected to the fourth conductor or an open state in which the terminal connected to the second conductor is not allowed to be electrically conducted to the terminal connected to the fourth conductor.

Citation List

Patent Literature

[PTL 1] Japanese Patent No. 4422064

Summary of Invention

Technical Problem

In the above-described indoor lighting lamp for a vehicle, some indoor lighting lamps use a circuit, what is called a bus bar, which is formed by applying a stamping work or a bending work to an electrically conductive metal plate in place of the wire harness.

In a contact structure of a lighting switch using a bus bar, as shown in Figs. 20A and 20B, a pair of electrically conducting contact pieces 220 are used which are provided so as to increase an angle from a switch operating part to an end part (see Fig. 20A) so that the electrically conducting pieces respectively come into contact with the bus bar 210. Namely, contacts 210a and 210b of the bus bar side which are allowed to come into contact with the one pair of electrically conducting contact pieces 220 are provided at positions separated from each other in a longitudinal direction or a transverse direction (see Fig. 20B).

Accordingly, a dimension of the bus bar in the longitudinal direction or the transverse direction is increased. As a result, a problem arises that an installed area is enlarged.

The present invention is devised by considering the above-described problem and it is an object of the present invention to provide a contact structure of a lighting switch which can suppress the increase of an installed area and an indoor lighting lamp for a vehicle having the contact structure of the lighting switch incorporated therein.

Solution to Problem

According to one aspect of the present invention, there is provided a contact structure of a lighting switch comprising:

a bus bar having a circuit formed in an electrically conductive plate shaped member; and

an electrically conducting contact piece part which serves to electrically conduct to each other two contacts of a plurality of contacts formed in the bus bar in accordance with an operating mode of a light source by a switch operation, wherein

an end part of the bus bar is folded back so as to have a U shaped section, so that an end part folded back part is formed which has one pair of opposed plate shaped parts including a lower opposed plate shaped part and an upper opposed plate shaped part opposed to each other in a vertical direction,

the bus bar has a lower bus bar part formed in the lower opposed plate shaped part and an upper bus bar part formed in the upper opposed plate shaped part, and the electrically conducting contact piece part has a bent form bent so as to suppress an extent in a longitudinal direction or a transverse direction and includes a lower contact which is allowed to come into contact with the lower bus bar part and an upper contact which is allowed to come into contact with the upper bus bar part.

The electrically conducting contact piece part may have the bent form substantially in a dogleg shape and may be arranged so that the bent part is surrounded by the end part folded back part.

The upper contact may be allowed to come into contact with a lower surface of the upper bus bar part.

According to another aspect of the present invention, there is provided an indoor lighting lamp for a vehicle which carries out a lighting operation according to an operating mode of a light source by a switch operation, wherein the contact structure of the lighting switch according to any one of above mentioned constructions is incorporated.

Advantages Effects of Invention

In the contact structure of the lighting switch according to one aspect of the present invention, the end part of the bus bar is folded back so as to have the U shaped section. Thus, the end part folded back part is formed which has the one pair of opposed plate shaped parts opposed to each other in a vertical direction. Accordingly, the bus bar has the lower bus bar part formed in the lower opposed plate shaped part and the upper bus bar part formed in the upper opposed plate shaped part. The electrically conducting contact piece part has the bent form bent so as to suppress an extent in the longitudinal direction or the transverse direction, and includes, as the contact structure of the lighting switch, the lower contact which is allowed to come into contact with the lower bus bar part and the upper contact which is allowed to come into contact with the upper bus bar part. Thus, an increase of the width of the bus bar can be suppressed in the longitudinal direction or the transverse direction. As a result, the increase of an installed area can be suppressed.

Further, in the contact structure of the lighting switch according to another aspect of the present invention, the same effects as those of the above-described aspect of the present invention can be achieved. The electrically conducting contact piece part has the bent form substantially in a dogleg shape and is arranged so that the bent part is surrounded by the end part folded back part. Accordingly, the bent part in the electrically conducting contact piece part which is extended in the longitudinal direction or the transverse direction can be located in the end part folded back part. As a result, the increase of the width of the bus bar can be effectively suppressed in the longitudinal direction or the transverse direction.

Further, in the contact structure of the lighting switch according to still another aspect of the present invention, the same effects as those of the aspects of the present invention can be achieved. Since the upper contact is allowed to come into contact with the lower surface of the upper bus bar part, an end part of the electrically conducting conduct piece part is protected by the upper bus bar part. As a result, the electrically conducting contact piece part can be prevented from being deformed.

Further, since the indoor lighting lamp for the vehicle according to still another aspect of the present invention has the above-described contact structure of the lighting switch defined as above incorporated therein, the same effects as those of the above-described contact structure of the lighting switch defined above can be achieved. Brief Description of Drawings

Fig. 1 is an exploded perspective view of a contact structure of a lighting switch and an indoor lighting lamp for a vehicle having the contact structure of the lighting switch incorporated therein according to an exemplary embodiment of the present invention.

Fig. 2 is a perspective view showing that the indoor lighting lamp for the vehicle shown in Fig. 1 is seen from an indoor side.

Fig. 3 is a perspective view showing that the indoor lighting lamp for the vehicle shown in Fig. 1 is seen from a back side.

Figs. 4A and 4B are explanatory views for explaining that an end part of a bus bar shown in Fig. 1 is folded back so as to have a U-shaped section.

Fig. 5 is an enlarged perspective view of a switch part shown in Fig. 1. Fig. 6 is a view showing a periphery of a terminal holding part of a switch knob shown in Fig. 1.

Fig. 7 is a perspective view of a terminal shown in Fig. 1.

Fig. 8 is an explanatory view for explaining that an electrically conducting contact piece part shown in Fig. 1 is allowed to abut on the bus bar.

Fig. 9 is an explanatory view for explaining that the electrically conducting contact piece part shown in Fig. 1 is allowed to abut on the bus bar.

Figs. 10A to 10G are diagrams for explaining an attaching procedure of the indoor lighting lamp for the vehicle. Figs. 11A to 11C are explanatory views for explaining that an operating mode of a bulb is switched by a pressing operation of a central switch part by an operator.

Figs. 12A to 12C are explanatory views for explaining that the operating mode of the bulb is switched by the pressing operation of the central switch part by the operator.

Figs. 13A to 13C are explanatory views for explaining that the operating mode of the bulb is switched by the pressing operation of the central switch part by the operator.

Fig. 14 is a diagram showing that a lower contact is moved between a contact holding part of a first lower bus bar part, a contact holding part of a second lower bus bar part and an insulation holding part.

Fig. 15 is a diagram showing that the lower contact is located in a position of the contact holding part of the first lower bus bar part, a position of an insulating resin crest part and a position of the contact holding part of the second lower bus bar part.

Figs. 16A to 16C are diagrams showing a state of the electrically conducting contact piece part in accordance with the change of the position of the lower contact shown in Fig. 15.

Figs. 17A and 17B are explanatory views for explaining that the width of the bus bar can be reduced the more by the bus bar folded back in the end part in a longitudinal direction or in a transverse direction.

Figs. 18A to 18C are explanatory views for explaining that the electrically conducting contact piece part is protected by the bus bar in three positions of switch parts. Fig. 19 is a diagram showing a modified example of the exemplary embodiment of the present invention.

Figs. 20A and 20B are diagrams for explaining a usual technique. Description of Embodiments

Now, by referring to the drawings, a detailed description will be given to a preferred exemplary embodiment of a contact structure of a lighting switch and an indoor lighting lamp for a vehicle having the contact structure of the lighting switch incorporated according to the present invention.

(Exemplary Embodiment)

Fig. 1 is an exploded perspective view of a contact structure 1 of a lighting switch and an indoor lighting lamp 100 for a vehicle having the contact structure 1 of the lighting switch incorporated therein according to an exemplary embodiment of^'the present invention. Fig. 2 is a perspective view showing that the indoor lighting lamp 100 for the vehicle shown in Fig. 1 is seen from an indoor side. Fig. 3 is a perspective view showing that the indoor lighting lamp 100 for the vehicle shown in Fig. 1 is seen from a back side. Figs. 4A and 4B are explanatory views for explaining that an end part 50a of a bus bar 50 shown in Fig. 1 is folded back so as to have a U-shaped section. Fig. 5 is an enlarged perspective view of a switch part 70 shown in Fig. 1. Fig. 6 is a view showing a periphery of a terminal holding part 76 of a switch knob 74 shown in Fig. 1. Fig. 7 is a perspective view of a terminal 80 shown in Fig. 1. Fig. 8 is an explanatory view for explaining that an electrically conducting contact piece part 82 shown in Fig. 1 is allowed to abut on the bus bar 50. Fig. 9 is an explanatory view for explaining that the electrically conducting contact piece part 82 shown in Fig. 1 is allowed to abut on the bus bar 50.

The indoor lighting lamp 100 for the vehicle according to the exemplary embodiment of the present invention is arranged in, for instance, a ceiling of the vehicle to light an interior of the vehicle. As shown in Fig. 1 , the indoor lighting lamp 100 for the vehicle includes a housing 10 fixed to the ceiling of the interior of the vehicle, a lens 30 attached to the housing 10 so as to close an opening of an interior side of the housing 10 and a lighting function part 40 having a light source accommodated in the housing 10.

Initially, the housing 10 will be described below.

The housing 10 is formed with an insulating synthetic resin and is an accommodating vessel having a rectangular form in its outer form in which the lighting function part 40 is accommodated. To the housing 10, the lens 30 is attached so as to close an opening part 10a of the interior side.

More specifically, in the housing 10, switch accommodating parts 11 which respectively accommodate a below-described right switch part, a left switch part and a central switch part are arranged in a right position, a left position and a central position along a longitudinal direction of the housing.

In the switch accommodating parts 11 respectively, one pairs of cylindrical shaft parts 12 protrude in opposed inner side surfaces 11a and the pairs of cylindrical shaft parts 12 are respectively fitted to circular openings of below-described bearing plate parts provided in the switch parts.

Further, as shown in Fig. 14, the housing 10 has an insulation holding part 13 formed in the shape of a trough so as to hold a lower contact 84 in a holding position of the lower contact 84 in a turning off mode of the below-described central switch part 73. The insulation holding part 13 is provided so as to have the same height as that of a below-described first lower bus bar part and a second lower bus bar part and to be arranged adjacently to the second lower bus bar part.

Further, as shown in Fig. 14, the housing 10 has a crest shaped insulating resin crest part 14 provided between the contact holding parts of the first lower bus bar part and the second lower bus bar part so as to be a crest between two troughs. Since the insulating resin crest part 14 is provided, the movement of the lower contact is guided between the contact holding parts of the first lower bus bar part and the second lower bus bar part.

Now, the lens 30 will be described below.

The lens 30 is formed in a rectangular shape in its outer form corresponding to the form of the housing 10 to close an opening 10a of the interior side of the housing 10. The lens 30 is formed with a light transmitting material so that lights emitted from bulbs respectively accommodated in the housing 10 are transmitted to the interior side. In the lens 30, switch insert opening parts 31 are respectively formed at positions corresponding to switch accommodating parts 11 of the housing 10. Accordingly, when the switch parts 70 are respectively accommodated in the switch accommodating parts 11 , operating surfaces of the switch parts are respectively exposed to the interior side through the switch insert opening parts 31.

Further, the lens 30 has engaging walls 32 protruding at four positions on a back surface 30b. The engaging walls 32 are engaged with metal clips 16 respectively attached to the housing 10 so that the lens 30 may be held and fixed to the housing 10.

Now, the lighting function part 40 will be described below. The lighting function part 40 includes, as shown in Fig. 1 , the bus bar 50 having a circuit formed in an electrically conductive plate shaped member, two bulbs 60 as the light sources and the switch part 70 which can switch an operating mode of the light source by a switching operation.

The bus bar 50 is attached to the housing 10 under a state that bulb holding parts 51 are formed in the electrically conductive plate shaped member, and then, form a separated circuit by a press.

In the bus bar 50 according to the exemplary embodiment of the present invention, an end part 50a is folded back so as to have a U shaped section. Thus, an end part folded back part 53 is formed which has one pair of opposed plate shaped parts 52 opposed to each other in a vertical direction. Accordingly, there are provided a lower bus bar part 54 formed in the lower opposed plate shaped part 52 of the one pair of opposed plate shaped parts 52 and an upper bus bar part 55 formed in the upper opposed plate shaped part 52 of the one pair of opposed plate shaped parts 52.

In such a bus bar 50, as shown in Fig. 4A, the bulb holding parts 51 are formed. Then, as shown in Fig. 4B, the end part 50a is folded back so as to have the U shaped section, so that the end part folded back part 53 is formed which has the one pair of opposed plate shaped parts 52 opposed to each other in the vertical direction.

The lower bus bar part 54 includes the first lower bus bar part 54a and the second lower bus bar part 54b which hold a contact state with the below-described lower contact 84. The first lower bus bar part 54a and the second lower bus bar part 54b are respectively separated from each other and have contact holding parts 54aa and 54bb formed in the shapes of troughs so as to easily hold the contact state with the lower contact 84.

The switch part 70 includes the right switch part 71 , the left switch part 72 and the central switch part 73 which are accommodated in the switch accommodating parts 11 respectively arranged in three positions of the housing 10. The switch part 70 is a switch for switching a turning on operation and a turning off operation of the bulbs 60 respectively.

The central switch part 73 is a switch for switching an operating mode of each of the bulbs 60.

The operating mode is classified into three kinds of a turning on mode M1 , a mode M2 meeting a door opening and closing operation and a tuning off mode M3.

The turning on mode M1 makes it possible to supply an electric power to the bulbs 60 respectively and turn on and turn off the bulbs 60 respectively by the right switch part 71 and the left switch part 72.

The mode M2 meeting the door opening and closing operation allows the bulbs 60 respectively to be turned on and turned off in accordance with the opening and closing operation of the door of a vehicle not shown in the drawing. The turning off mode M3 cuts off a supply of the electric power to the bulbs 60 respectively to turn off the bulbs 60.

The right switch part 71 is a switch which individually switches the turning on mode M1 and the mode M2 meeting the door opening and closing operation of the bulb 60 arranged in the right side of the housing 10.

The left switch part 72 is a switch which individually switches the turning on mode M1 and the mode M2 meeting the door opening and closing operation of the bulb 60 arranged in the left side of the housing 10. Here, the switch part 70 will be more specifically described by using the central switch part 73. Since the right switch part 71 and the left switch part 72 have the same contact structures as the contact structure of the central switch part 73, a specific explanation will be omitted.

The central switch part 73 includes the switch knob 74 and the terminal

80 fixed to the switch knob 74.

The switch knob 74 includes a switch base part 75 and the terminal holding part 76 on which the terminal 80 is supported.

As shown in Fig. 5, the switch base part 75 has a substantially rectangular parallelepiped form and serves as a base part of a switch operation. On an upper part of the switch base part 75, an operating surface 75a is formed which is pressed by an operator during the switch operation. The operating surface 75a is formed in the shape of a curved surface having both side parts 75b protruding and a central part 75c recessed so that the switch knob 74 is swung by a pressing operation to switch the three kinds of operating modes.

On a back side surface 75d of the operating surface 75a of the switch base part 75, that is, the surface 75d of the switch accommodating part side, the one pair of bearing plate parts 75e are provided. The one pair of cylindrical shaft parts 12 not shown in the drawing which are provided in the switch accommodating part 11 are respectively fitted to the circular openings 75f formed in the bearing plate parts 75e. Thus, the switch knob 74 is supported by the housing 10 so as to be freely swung.

As shown in Fig. 6, the terminal holding part 76 has one pair of square tube shaped holding posts 76a standing upright on the surface 75d of the switch accommodating part 11 side of the switch base part 75. The one pair of holding posts 76a function as holding parts for holding the terminal 80. On opposed surfaces 76b of the one pair of holding posts 76a to each other, holding parts 77 are provided which hold respectively side parts 81a of a below-described held part 81 of the terminal 80. Both the side parts 81a of the below-described held part 81 are held by the holding parts 77.

The terminal 80 is, as shown in Fig. 7, substantially formed in the shape of a character T and includes the held part 81 and the electrically conducting contact piece part 82.

The held part 81 is a part forming a transverse line of the character T.

The held part 81 is a part held on the switch knob 74 by the terminal holding part 76.

The electrically conducting contact piece part 82 serves to electrically conduct to each other two contacts of a plurality of contacts formed in the bus bar 50 according to the operating mode of the light source by the switch operation. The electrically conducting contact piece part 82 is a part forming a longitudinal line of the character T and has a bent form bent so as to suppress an extent in the longitudinal direction or the transverse direction. More specifically, the electrically conducting contact piece part 82 is formed substantially in a dogleg shape and a bent part 83 is arranged so as to be surrounded by the end part folded back part 53.

The electrically conducting contact piece part 82 is provided with, as the contact structure 1 of the lighting switch, the lower contact 84 which is allowed to come into contact with the lower bus bar part 54 and an upper contact 85 which is allowed to come into contact with the upper bus bar part 55.

The lower contact 84 is provided to be inclined relative to the held part 81 so that the lower contact 84 may come into contact with the lower bus bar part 54 and has a recessed contact part 86 held by the contact holding parts 54aa and 54bb.

The recessed contact part 86 has a recessed form in section having a bottom wall 86a and one pair of side walls 86b standing upright in both edges of the bottom wall 86a. The recessed contact part 86 is provided so as to be inclined so that as the one pair of side walls 86b are separated more from the bottom wall 86a, their end parts 86c are separated more from each other.

The recessed contact part 86a is easily held in the contact holding parts 54aa and 54bb formed in the shapes of the troughs. When the switch knob 74 is swung so that the terminal 80 is moved between the contact holding parts 54aa and 54bb respectively or the insulation holding part 13, since the one pair of side walls 86b are inclined along the trough, the terminal 80 is smoothly moved.

The upper contact 85 is a part bent from the lower contact 84 and further extended in the longitudinal direction.

An end part 85a has a horizontally bent part 85b bent in a horizontal direction. As shown in Fig. 8 and Fig. 9, since the upper contact 85 is formed in an upper part of the electrically conducting contact piece part 82 formed substantially in the dogleg shape, an upward urging force can be obtained. Accordingly, an upper surface 85c of the horizontally bent part 85b is assuredly allowed to abut on a lower surface 55a of the upper bus bar part 55.

Now, an attaching procedure of the indoor lighting lamp 100 for the vehicle will be described below by referring to Fig. 10A to Fig. 10G. Fig. 10A to Fig. 10G are the diagrams for explaining the attaching procedure of the indoor lighting lamp 100 for the vehicle.

Initially, the operator attaches the bus bar 50 to the housing 10 (see Fig. 10A). At this time, for instance, set holes 56 provided in a plurality of positions of the bus bar 50 are allowed to correspond to positioning pins 15 provided in the housing 10 so that the bus bar 50 may be positioned to a prescribed attaching position of the housing 10.

Then, the operator welds the positioning pins 15 to fix the bus bar 50 to the housing 10 (see Fig. 10B).

After that, the operator attaches the metal clips 16 for fixing the lens to the four positions of the housing 10 (see Fig. 10C).

Then, the operator attaches each of the terminals 80 to each of the switch knobs 74 (see Fig. 10D). At this time, the side parts 81a of the held part 81 of the terminal 80 are respectively held by the holding parts 77.

After that, the operator attaches each of the switch parts 70 to the housing 10 (see Fig. 10E). At this time, the one pair of cylindrical shaft parts 12 provided in the switch accommodating part 11 of the housing 10 are respectively fitted to the circular openings 75f formed in each of the switch knobs 74. Thus, the switch knob 74 is supported in the switch accommodating part 11 so as to be freely swung.

Subsequently, after the bulbs 60 are respectively attached to the housing 10 (see Fig. 10F), the operator attaches the lens 30 to the housing 10 (see Fig. 10G). At this time, the lens 30 is held and fixed to the housing 10 by the metal clips 16. Now, as more specifically described below by referring to Fig. 11 A to Fig. 13C, the operating mode of the bulb 60 is switched by a pressing operation of the central switch part 73 by the operator. Fig. 11 A to Fig. 13C are explanatory views for explaining that the operating mode of the bulb 60 is switched by the pressing operation of the central switch part 73 by the operator.

Initially, an explanation will be given to a case that the operator carries out the pressing operation to select the turning on mode M1.

As shown in Figs. 11 A to 11C, when the right side part of the operating surface is pressed by the operator, the switch knob 74 is swung so as to be inclined rightward on the cylindrical shaft parts 12 as axes (see Fig. 11 B). Thus, the electrically conducting contact piece part 82 is moved to a left side of a moving range. Thus, the lower contact 84 is allowed to abut on the first lower bus bar part 54a. More specifically, the lower contact 84 is held by the contact holding part 54aa of the first lower bus bar part 54a and the upper contact 85 is allowed to abut on the upper bus bar part 55 (see Fig. 11A and Fig. 11B). Thus, an electric current is supplied from the first lower bus bar part 54a to the upper bus bar part 55 through the electrically conducting contact piece part 82 to obtain a flow of the electric current corresponding to the turning on mode (see Fig. 11C).

Now, an explanation will be given to a case that the operator carries out the pressing operation to select the mode M2 meeting the door opening and closing operation.

As shown in Figs. 12A to 12C, when the operator presses the central part of the operating surface 75a, the switch knob 74 is swung on the cylindrical shaft parts 12 as the axes (see Fig. 12B). Thus, the electrically conducting contact piece part 82 is moved to a center of the moving range. Thus, the lower contact 84 is allowed to abut on the second lower bus bar part 54b. More specifically, the lower contact 84 is held by the contact holding part 54bb of the second lower bus bar part 54b and the upper contact 85 is allowed to abut on the upper bus bar part 55 (see Fig. 12A and Fig. 12B). Thus, the electric current is supplied from the second lower bus bar part 54b to the upper bus bar part 55 through the electrically conducting contact piece part 82 to obtain a flow of the electric current corresponding to the mode M2 meeting the door opening and closing operation (see Fig. 12C).

Now, an explanation will be given to a case that the operator carries out the pressing operation to select the turning off mode M3.

As shown in Figs. 13A to 13C, when the operator presses the left side part of the operating surface 75a, the switch knob 74 is swung on the cylindrical shaft parts 12 as the axes so as to be inclined leftward (see Fig. 13B). Thus, the electrically conducting contact piece part 82 is moved to a right side of the moving range. Thus, the lower contact 84 is held by the insulation holding part 13 (see Fig. 13A and Fig. 13B). Thus, since the electric current is cut off by the insulation holding part 13, the electric current is cut off correspondingly to the turning off mode M3 (see Fig. 13C).

Now, as described below by referring to Fig. 14 to Fig. 16C, when the central switch part 73 is pressed, a sense of switching operation of the switch can be obtained. Fig. 14 is a diagram showing that the lower contact 84 is moved between the contact holding part 54aa of the first lower bus bar part 54a, the contact holding part 54bb of the second lower bus bar part 54b and the insulation holding part 13. Fig. 15 is a diagram showing that the lower contact 84 is located in a position of the contact holding part 54aa of the first lower bus bar part 54a, a position of the insulating resin crest part 14 and a position of the contact holding part 54bb of the second lower bus bar part 54b. Figs. 16A to 16C are diagrams showing a state of the electrically conducting contact piece part 82 in accordance with the change of the position of the lower contact 84 shown in Fig. 15.

At the time of pressing the central switch part 73, when the lower contact 84 is moved between, as shown in Fig. 14 to Fig. 16C, the trough shaped contact holding part 54aa of the first lower bus bar part 54a, the trough shaped contact holding part 54bb of the second lower bus bar part 54b and the trough shaped insulation holding part 13, the electrically conducting contact piece part 82 gets over the crest shaped insulating resin crest part 14 and moves by using an elasticity. Accordingly, the sense of switching operation of the switch can be obtained.

The above-described indoor lighting lamp 100 for the vehicle includes the contact structure 1 of the lighting switch. In the contact structure 1 of the lighting switch, the end part 50a of the bus bar 50 is folded back so as to have the U shaped section. Thus, the end part folded back part 53 is formed which has the one pair of opposed plate shaped parts 52 opposed to each other in a vertical direction. Accordingly, the lower bus bar part 54 formed in the lower opposed plate shaped part 52 of the one pair of opposed plate shaped parts 52 and the upper bus bar part 55 formed in the upper opposed plate shaped part 52 of the one pair of opposed plate shaped parts 52 are provided. The electrically conducting contact piece part 82 has the bent form bent so as to suppress an extent in the longitudinal direction or the transverse direction, and includes, as the contact structure 1 of the lighting switch, the lower contact 84 which is allowed to come into contact with the lower bus bar part 54 and the upper contact 85 which is allowed to come into contact with the upper bus bar part 55.

Accordingly, as shown in Figs. 17A and 7B, when the end part 50a of the bus bar 50 is folded back (see Fig. 17B), a width W of the bus bar 50 in a longitudinal direction or a transverse direction can be more reduced than a usual bus bar 210 (see Fig. 17A) whose end part 230 is not folded back.

Further, as shown Figs. 18A to 18C, since the switch parts 70 of the three positions are surrounded by the bus bar 50, the electrically conducting contact piece parts 82 are protected by the bus bar 50.

In the contact structure 1 of the lighting switch according to the exemplary embodiment of the present invention, the end part 50a of the bus bar 50 is folded back so as to have the U shaped section. Thus, the end part folded back part 53 is formed which has the one pair of opposed plate shaped parts 52 opposed to each other in a vertical direction. Accordingly, the lower bus bar part 54 formed in the lower opposed plate shaped part 52 and the upper bus bar part 55 formed in the upper opposed plate shaped part 52 are provided. The electrically conducting contact piece part 82 has the bent form bent so as to suppress an extent in the longitudinal direction or the transverse direction, and includes, as the contact structure 1 of the lighting switch, the lower contact 84 which is allowed to come into contact with the lower bus bar part 54 and the upper contact 85 which is allowed to come into contact with the upper bus bar part 55. Thus, an increase of the width of the bus bar 50 can be suppressed in the longitudinal direction or the transverse direction. As a result, the increase of an installed area can be suppressed.

Further, in the contact structure 1 of the lighting switch according to the exemplary embodiment of the present invention, the electrically conducting contact piece part 82 has the bent form substantially in a dogleg shape and is arranged so that the bent part 83 is surrounded by the end part folded back part 53. Accordingly, the bent part 83 in the electrically conducting contact piece part 82 which is extended in the longitudinal direction or the transverse direction can be located in the end part folded back part 53. As a result, the increase of the width of the bus bar 50 can be effectively suppressed in the longitudinal direction or the transverse direction.

Further, in the contact structure 1 of the lighting switch according to the exemplary embodiment of the present invention, since the upper contact 85 is allowed to come into contact with the lower surface 55a of the upper bus bar part 55, an end part of the electrically conducting conduct piece part 82 is protected by the upper bus bar part 55. Consequently, the electrically conducting contact piece part 82 can be prevented from being deformed.

Further, since the indoor lighting lamp 100 for the vehicle according to the exemplary embodiment of the present invention has the contact structure 1 of the lighting switch incorporated therein, the same effects as those of the contact structure 1 of the lighting switch can be achieved.

(Modified Example)

Now, referring to Fig. 9, a contact structure 2 of a lighting switch as a modified example of the contact structure 1 of the lighting switch according to the exemplary embodiment of the present invention will be described below. Fig. 19 is a sectional view of main parts of the contact structure 2 of the lighting switch as the modified example of the contact structure 1 of the lighting switch according to the exemplary embodiment of the present invention. The contact structure 2 of the lighting switch of the modified example is different from the contact structure 1 of the lighting switch of the exemplary embodiment in view of a point that an electrically conducting contact piece part 90 is formed in a hook type bent shape.

Other structures are the same as those of the exemplary embodiment and the same component parts as those of the exemplary embodiment are designated by the same reference numerals.

The contact structure 2 of the lighting switch of the modified example can achieve the same effects as those of the contact structure 2 of the lighting switch of the exemplary embodiment.

The invention created by the inventor is specifically described in accordance with the above-described exemplary embodiment of the invention. However, the present invention is not limited to the above-described exemplary embodiment of the invention and may be variously changed within a range that does not depart from a gist thereof. The present application is based on Japanese patent application No.

2011-168279 filed on August 1 , 2011 , and the contents of the patent application are incorporated herein by reference.

Industrial Applicability

The present invention is useful for providing a contact structure of a lighting switch capable of suppressing the increase of an installed area. Reference Signs List

1 , 2 contact structure of lighting switch 1 Chousing 10a..opening part 11...switch accommodating part 11a...inner side surface 12... cylindrical shaft part 13... insulation holding part 14... insulating resin crest part 15... positioning pin 16..metal clip 30..lens 30b...back surface 31...switch insert opening part 32...engaging wall 40..lighting function part 50..bus bar 50a.. end part 51... bulb holding part 52....opposed plate shaped part 53...end part folded back part

54... lower bus bar part 54a... first lower bus bar part 54b... second lower bus bar part 54aa, 54bb... contact holding part 55... upper bus bar part 55a...lower surface 56...set hole 60...bulb 70...switch part 71... right switch part 72... left switch part 73... central switch part 74... switch knob 75... switch base part 75a... operating surface 75b... side part 75c... central part 75d... back surface 75e... bearing plate part 75f... circular opening 76...terminal holding part

76a... holding post 76b... surface 77... holding part 80... terminal 81... held part 81 a.... side part 82, 90.... electrically conducting contact piece part 83... bent part 84... lower contact 85... upper contact 85a... end part 85b... horizontally bent part 85c... upper surface

86.. recessed contact part 86a... bottom wall 86b... side wall 86c...end part 100... indoor lighting lamp for vehicle 200.... contact structure of lighting switch 210... bus bar 210a, 210b... contact 220... electrically conducting contact piece M1 , M2, M3... operating mode

Claims

1. A contact structure of a lighting switch comprising:

the bus bar has a lower bus bar part formed in the lower opposed plate shaped part and an upper bus bar part formed in the upper opposed plate shaped part, and

the electrically conducting contact piece part has a bent form bent so as to suppress an extent in a longitudinal direction or a transverse direction and includes a lower contact which is allowed to come into contact with the lower bus bar part and an upper contact which is allowed to come into contact with the upper bus bar part.

2. A contact structure of a lighting switch according to claim 1 , wherein the electrically conducting contact piece part has the bent form substantially in a dogleg shape and is arranged so that the bent part is surrounded by the end part folded back part.

3. A contact structure of a lighting switch according to claim 1 or 2, wherein the upper contact is allowed to come into contact with a lower surface of the upper bus bar part.

4. An indoor lighting lamp for a vehicle which carries out a lighting operation according to an operating mode of a light source by a switch operation, wherein the contact structure of the lighting switch according to any one of claims 1 to 3 is incorporated.