Patent Document

FIELD OF INVENTION  
       [0001]     The present invention relates generally to slide switch assemblies used to control a lamp associated with an automotive room lamp system in which a member soldered to the printed circuit board loaded with spot lights (e.g., light emitting diodes (LEDs)) is used as a fixed contact for the slide switch.  
       BACKGROUND OF THE INVENTION  
       [0002]     A conventional slide switch for controlling a blinking lamp of an automotive room lamp system is disclosed, for example, in U.S. Pat. No. 6,402,570 (the entire content of which is incorporated expressly hereinto by reference). In accordance with the conventional slide switch disclosed therein, bus bars are arranged on the back side of the base in which the lamp is accommodated. The base body has an accommodation portion formed therein to receive a traveling contact member. Some portions of the bus bars are bent to extend along the inner walls to thereby serve as fixed contacts. When the slide switch is turned on, the lamp and the power source are thus connected to illuminate the lamp by the bus bars.  
         [0003]     Recently, in this connection, there was developed a device equipped with a light emitting diode in the base thereof for illuminating localized portions of an automotive interior, such as a cup holder or the like. In order to install such a light emitting diode in the base portion, the diode is required to be soldered to the printed circuit board, with the printed circuit board then in turn being loaded into the base body.  
         [0004]     In the situation whereby the printed circuit board and the slide switch are arranged together on a single base body, it is required that a connector is used to electrically connect the printed circuit board and the slide switch or that the printed circuit board and the fixed contacts of the slide switch are connected by use of lead wires. Therefore, such arrangements can give rise to problems such that an increasing number of parts are required while the connectors are to be connected or that time consuming work for soldering the lead wires is required, thereby resulting in increased manufacturing costs.  
       SUMMARY OF THE INVENTION  
       [0005]     The present invention has been made in order to solve the above mentioned problems and has an one of its objects to provide a fixed contact structure of a slide switch which can improve assembly. More specifically, according to the present invention, conductors attached to the conducting patterns of the printed circuit board are used as fixed contacts of the slide switch to ensure that the printed circuit board and the slide switch are readily connected without incorporation of a slide switch and a connector.  
         [0006]     The fixed contact structure of a slide switch of the present invention is provided in order to realize the above mentioned object by comprising a housing; an accommodation section formed in the housing to receive a slider such that the slider is adapted for sliding movement therein; traveling contacts having contact faces and accommodated in the slider such that the contact faces are exposed outside thereof, and a printed circuit board having fixed contact plates attached to the printed circuit board; the printed circuit board being adapted to be loaded onto the housing such that the fixed contact plates are brought into electrical conduction with the traveling contacts.  
         [0007]     The fixed contact plates are preferably composed of fixation bases adapted to be soldered to the conduction pattern and contact portions bent to rise outwardly from the fixation bases. The accommodation section is most preferably defined by a partition wall having openings such that the contact portions of the fixed contact plates are adapted to be exposed therethrough.  
         [0008]     The contact portions are preferably further bent to form engagement portions adapted for engagement with the openings.  
         [0009]     The engagement portions are preferably formed with relatively narrow-width cutouts whereas the partition wall is composed of upright portions defining the openings. These upright portions are therefore adapted to hold the cutouts in the fixed contact plates.  
         [0010]     The printed circuit board preferably has a back side on which bus bars are arranged thereon, the bus bars being adapted for connection with electrical loads, such as illumination lamps that may be equipped on the printed circuit board.  
         [0011]     A microphone, a connector terminal box and/or a light emitting diode may preferably be mounted onto the printed circuit board.  
         [0012]     Still further, the partition wall defining the accommodation section preferably has an inner wall with which the fixed contact plates are set in flush to assure smooth sliding movement of the traveling contacts when the slider is in motion.  
         [0013]     As detailed in the foregoing, the present invention is especially embodied in an accommodation section which is formed in the housing to receive a slider, the printed circuit board being loaded (mounted) onto the housing such that the fixed contacts plates are brought into electrical connection with the traveling contacts. Therefore, the fixed contacts and the slide switch are easily connected to improve its functionality and working efficiency.  
         [0014]     The fixed contact plates are preferably soldered to the printed circuit board and a component part thereof is secured to the wall defining the accommodation section by means of an engagement portion to assure firm fixation of the fixed contact plates to the accommodation section. As a result, the printed circuit board is firmly held to the base body in which the accommodation section is formed.  
         [0015]     The backside of the base body may be provided with bus bars for connection to the electrical loads, such as illumination lamps installed to the base body. As a result it is possible to connect the lamps and the printed circuit board arranged with other electrical loads, such as a light emitting diode, merely by means of bus bars.  
         [0016]     The fixed contact plates are most preferably set flush with the inner wall surface of the accommodation section. Such a mounting arrangement provides beneficial effects such as promoting a smooth sliding movement of the traveling contacts on the slider against the inner wall surface of the accommodation section. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0017]     Reference will be made to the accompanying drawings wherein like reference numerals throughout the various Figures denote like structural elements, and wherein:  
         [0018]      FIG. 1  is a perspective view of the automotive room lamp assembly partly broken, the fixed contact structure of a slide switch of the present invention being applied to the automotive room lamp assembly;  
         [0019]      FIG. 2  is a front view of the assembled state of the fixed contact structure shown in  FIG. 1 ;  
         [0020]      FIG. 3  is an exploded perspective view of the switch box as shown in  FIG. 1 ;  
         [0021]      FIG. 4  is a plan view of the essential portion of the slide switch;  
         [0022]      FIG. 5  is a sectional view of  FIG. 4 ;  
         [0023]      FIG. 6  is a sectional view of the traveling contacts of the slide switch;  
         [0024]      FIG. 7  is a plan view of the assembled slide switch;  
         [0025]      FIG. 8   a  is a plan view of the slider in motion in an OFF state and  FIG. 8   b  is a plan view of the same in an ON state;  
         [0026]      FIG. 9  is a plan view of the light emitting diode being mounted to the printed circuit board;  
         [0027]      FIG. 10  is a cross sectional view of the light emitting diode being soldered to the printed circuit board; and  
         [0028]      FIG. 11  is the diagram of a circuit for controlling other illumination lights by means of the slide switch. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0029]     In the fixed contact structure according to the present invention, an accommodation section is formed in the housing thereof to receive a slider therein, the housing being loaded with a printed circuit board such that fixed contact plates attached to the printed circuit board are brought into electrical conduction with the traveling contacts.  
         [0030]     Hereinafter, embodiments of the fixed contact structure of the present invention being applied to the automotive room lamp will be explained with reference to the drawings.  
         [0031]     Referring to  FIG. 1  which is a perspective view of the automotive room lamp system in general, the numeral  1  denotes a box-shaped base body formed by injection molding or the like, the body being divided into three chambers aligned generally in a longitudinal direction. In the respective left hand and right hand chambers, lamps and push switches are accommodated while lens plates  1   a  are pivotally supported thereto on the central chamber sides thereof in cantilever fashion.  
         [0032]     When each lens plate  1   a  is pressed at an end portion thereof opposite to the pivotal end thereof, the above mentioned push switches are turned on to light the lamp and when the lens plate  1   a  is pressed again in a similar way, the push switch is operated to switch off the lamp. The thus structured automotive room lamp system is known as disclosed in U.S. Pat. No. 6,273,593 (the entire content of which is expressly incorporated hereinto by reference). Furthermore, bus bars (not shown) to connect the lamp and the push switch are mounted to the back side of the base body  1 .  
         [0033]     The numeral  2  denotes a switch box to be accommodated in the central chamber of the base body  1 , the structure of the box being shown in greater detail in  FIGS. 2 and 3 . As is shown, the switch box  2  is composed of a front plate  21 , a printed circuit board  22  mounted to the interior of the front plate  21  by means of screws or the like. A back plate  23  is engaged with a hole  21   a  in the front plate  21  by way of claw  23   a  from the back thereof so as to be made integral with the front plate  21 . A slider or traveling contact member  24  has a knob  24   a  protruding through a slot  21   c  in the front plate  21 . The slot  21   c  thus provides access to the slider  24  to allow lateral sliding manipulation of the same.  
         [0034]     The front plate  21  has a partition wall  21   d  which defines an accommodation section  21   b.  The partition wall  21   d  has upright portions  21   d   1  which define six cutouts  21   i,  each upright portion  21   d   1  being formed with steps at its upper portion. The front plate  21  is formed with a transparent window  21   e  for letting out the light from a light emitting diode  22   d  which will be explained later. On the back side of the front plate  21 , there is further formed a light shielding wall  21   f  to surround the transparent window  21   e.  (See  FIG. 10 ) It is to be noted in this connection that the numeral  21   g  denotes a sound collecting hole for picking up sound for a microphone to allow a hand free use of a cellular phone, for example.  
         [0035]     The slider  24  slidably accommodated in the accommodation section  21   b  is oriented such that the knob  24   a  thereof protrudes through the slot  21   c  in the front plate  21 . As shown in  FIG. 6 , the slider  24  is provided with two traveling contacts  24   b  and having contact faces and urged by springs  24   c  toward the partition walls  21   d  such that the contact faces are exposed outside thereof, each traveling contact  24   b  being arranged for the contact faces to short any two of the fixed contact plates  22   c  to be described later on.  
         [0036]     The printed circuit board  22  is soldered with a microphone  22   a,  a connector terminals  22   b  to be led out into the connector box  22   b  for connecting the bus bars and the power source to the connectors, fixed contact plates  22   c  to be engaged with the upright portions  21   d   1  of the partition wall  21   d  in the front plate  21  and the light emitting diode  22   d  to do spot illuminating. (See  FIGS. 9 and 10 )  
         [0037]     As shown in  FIGS. 4 and 5 , the respective fixed contact plates  22   c  have fixation bases  22   c   1  to be connected to the conduction patterns of the printed circuit board  22 , contact portions  22   c   2  rising from the fixation bases  22   c   1  and engagement portions  22   c   4  having cutouts  22   c   3  therein such that the entire structure are channel shaped as viewed from the side.  
         [0038]     The procedure of bringing the fixed contact plates  22   c  into engagement with the partition walls  21   d  of the accommodation section  21   b  will be explained hereinafter. In this regard, it is to be noted that the fixed contact plates  22   c  are soldered to the printed circuit board  22 . Therefore, when the printed circuit board  22  is assembled with the front plate  21 , the engagement portions  22   c   4  of the contact plates  22   c  will be inserted into the generally U-shaped openings defined by the upright portions  21   d   1 . The relatively narrow width cutouts  22   c   3  in the fixed contact plates  22   c  are thereby received within and slidably guided downwardly by the upright portions  21   d   1 . During assembly, the fixed contact plates  22   c  will ultimately reach a lowermost extent of being guided downwardly along the upright portions  21   d   1 , at which time the upper engagement portions  22   c   4  of the contact plates  22   c  are brought into abutment with the steps  21   d   2  formed in the upright portions  21   d   1 . As such, the contact plates  22   c  will be seated in their final fixed position so as to be exposed through the openings of the upright portions  21   d   1 . In such a state, the printed circuit board  22  may then be further fastened to the front plate  21  by means of screws or the like to ensure that the fixed contact plates  22   c  are secured immovably to the partition wall  21   d  without play.  
         [0039]     The contact portions  22   c   2  of the contact plates  22   c  are thus positioned so as to be substantially flush with the surfaces of the upright walls  21   d.  Such a flush mounting of the contact portions  22   c   2  thereby ensures that the traveling contacts  24   b  of the slider  24  move relatively smoothly when the slider  24  within the accommodation section  21   b  is manipulated so as to slide relative to the fixed contact plates  22   c.    
         [0040]     It is to be noted that the accommodation portion  21   b  is also defined by an outer wall standing opposite to the partition wall  21   d.  The outer wall preferably has a patterned indented surface  21   h  formed in the inner side thereof so as to provide a clicking feel upon the sliding movement of the slider  24 . The switch box  2  is assembled into an integral body by securing the printed circuit board  22  to the front plate  21 , inserting the slider  24  into the accommodation portion  21   b , engaging the back plate  23  to the front plate  21  and then bringing a claw  23   b  formed in the back plate  23  into engagement with a hole  1   b  formed in the base body  1 . (See  FIG. 1 )  
         [0041]     In the preferred embodiment, the printed circuit board  22  is provided with two sets of fixed contact plates  22   c , the two sets being formed in separated positions, each set having three fixed contact plates  22   c . On the other hand, the slider  24  is provided with a pair of traveling contacts  24   c  in separated positions, thus enabling the slider  24  to cause the fixed contacts  22   b  to perform a two-step switching action while being slid. If the thus constructed slide switch is to be installed in a vehicle such as a minivan or the like having three rows of seats, the circuit as shown in  FIG. 11  will be required.  
         [0042]     More specifically, the push switches S 1  and S 2  incorporated with the slide switches to be used for a front seat illumination in a vehicle, the push switches S 3  and S 4  loaded with two lamps to be used for a middle seat illumination light and the switch S 5  loaded with two lamps for rear seat illumination are connected as shown in  FIG. 11  such that the operation of the middle seat and rear seat illumination lamps is controlled by sliding the front seat slide switch. It is to be noted in this connection that the numerals L 1  to L 5  denote lamps whereas the numeral S 6  denote a door switch to be turned on in response to the opening of a car door.  
         [0043]     Hereinafter, the control operation thereof will be explained. In case the traveling contacts of the respective switches S 1  to S 5  have been switched to the fixed contact side as shown while the traveling contact  24   b  is connected to the door contact of the fixed contact plate  22   c , the respective switches S 1  to S 5  are grounded by way of the door switch S 6  which is turned ON when the door is opened. In this state, all the lamps L 1  to L 5  connected to the respective switches S 1  to S 5  are lit. On the other hand, all the lamps L 1  to L 5  are turned off if the door is closed to open the door stitch S 6 .  
         [0044]     When the traveling contacts  24   b  of the slide switch are turned to the ON side of the fixed contact plates  22   c  while the switches S 1  to S 5  are as depicted, the traveling switch  24   b  is grounded regardless of the ON-Off position of the door switch S 6 , thus enabling all the illumination lamps L 1  to L 5  arranged at the driver&#39;s seat are brought into a lit state.  
         [0045]     Furthermore, if the respective switches S 1  to S 5  are switched to the opposite direction from the connection state, the respective fixed contacts are grounded such that the lamps at the respective seats are freely operated for lightening.  
         [0046]     The light emitting diodes  22   d  to be soldered to the printed circuit board  22  are inserted into a holder  25  secured to the printed circuit board  22  before the soldering is done. Thereafter, the lead wire  22   d   1  of the light emitting diode  22   d  is inserted into a through hole in the printed circuit board  22  for soldering.  
         [0047]     The holder  25  is formed of a resin in the shape of a rectangular sleeve having legs  25   a  diagonally designed to fit into holes formed in the printed circuit board  22 . The inside of the holder  25  is provided with a platform  25   b  to support the underside of the light emitting diode  22   d,  the platform  25   b  having a hole to allow the insertion of the lead wires  22   d   1 . Further, the holder  25  has a wall above the platform  25   b,  the wall having protruding members  25   c  to restrain the play of the light emitting diode  22   d.  The upper portions of the protruding members  25   c  are formed with slants  25   c   1  to allow smoother insertion of the light emitting diodes  22   d  into the holder  25 .  
         [0048]     The holder  25  is an open top type having an upper portion which flanks the light shielding wall  21   f  formed in the inner wall surface of the front face plate  21 . Therefore, when the light emitting diode  22   d  is energized to be lit, the light ray radiating from the light emitting diode  22   d  is emanated toward the transparent window  21   e  formed in the front plate  21  to do the spot illumination for the cup holders or the like installed inside the vehicle by the light ray therefrom.  
         [0049]     In general, visible light rays from the light emitting diode tend to be diffused. However, the light emitting diode used in the present invention is accommodated within the holder  25  to prevent light rays from emanating outside the opening in the holder  25 . Since the opening in the holder is positioned to extend in the light shielding wall  21   f,  light rays spreading out from the opening in the holder  25  are shielded by the light shielding wall  21   f  and are thereby prevented from being emitted from the room lamp per se.  
         [0050]     In the preferred embodiment of the present invention, although the explanation has been given only with respect to the automotive room lamp, it is needless to say that the invention can be applied to devices in which the operation of the circuit of the printed circuit board are controlled by electrically connecting the slide switches and the printed circuit board.

Technology Category: 5