Multi-purpose buckle sensor assembly

A multi-purpose buckle sensor assembly includes a hall sensor portion including a hail sensor and a printed enclosed in one package; a base plate including a metal pattern with a plurality of terminal portions for control and power lines formed in a predetermined pattern and a supporting plate including a plurality of terminal seats for connecting the connecting ends of control and power lines to the terminal portions; a movable member including at least two contact terminals for generating various control and a terminal block made of a heat-melted material in the form of a fork having three branches at the front portion and including at least one branch enclosing the connecting ends of the control and power lines electrically coupled to each other with the control terminal portions in corresponding power terminal seats, in which the hall sensor portion is cooperated with a buckle assembly.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention is related to providing a seatbelt buckle mounted in a vehicle, and particularly, to providing a multi-purpose buckle sensor assembly including a contact switch and a non-contact switch integrated into one body to detect the locking state and unlocking state of the seatbelt buckle at the same time.

2. Prior Arts

A conventional vehicle buckle is provided with a seatbelt, with which is mounted to a proper place in a vehicle. As being worn by an occupant, the seatbelt passes through and hangs on predetermined positions, for example three points, terminates into the buckle with a tongue connected to its end to be supported. The buckle is known to promote the safety of occupants in an abnormal condition.

The safety seatbelt buckle is supposed to identify on whether a driver and/or an occupant wears the seatbelt. The seatbelt buckle normally includes a mechanical switch such as a micro-switch to be operated with the tongue, together. Therefore, the micro-switch turns on or off in response to the insertion of the tongue thereinto, so that a warning lamp mounted on an instrument panel is lightened or put out to warn the non-wearing of the seatbelt to a driver and/or an occupant.

The safety seatbelt buckle further can include a non-contact switch such as a hall sensor to perform a self-diagnostic function of an electronic control unit such as ECU. Upon the seatbelt non-wearing of the occupant, the non-contact switch detects the abnormal states of the vehicle to force all warning lamps on the instrument panel to be lightened, while it enables the execution of the proper measures related to the traveling of the vehicle such as the limitation of a speed, the ready state for the operation of an airbag, etc. thereby enhancing the efficiency of a vehicle control.

But, the safety seatbelt buckle is configured so that the contact and/or non-contact switches are respectively or together mounted therein to recognize its locking state or non-locking state with being separated from each other. The configuration makes the mutual separated contact and non-contact switches mounted on their proper positions, mainly the bottom surface of a lower case, so the contact and/or non-contact switches are switched in response to the insertion of a tongue into the buckle in a predetermined lapse interval.

For example, a latch, an ejector or a moving member mounted in the buckle to be co-operated with the tongue operates these contact and/or non-contact switches. It means that their mounting place is limited and a separate mounting space is secured. Furthermore, the configuration may cause the malfunction of the switches due to the wrongly insertion of the tongue into the buckle.

In order to resolve these problems, the adoption of a non-contact switch is disclosed in U.S. Pat. No. 5,960,523 (Oct. 5, 1999) which is related to a seat belt buckle sensor. A sensor is used to monitor the presence and position of the tongue either directly or by measuring motion of the latch. For example, the full range of motion of the latch, both in its up and down motion and in its lateral motion in response to the seat belt tension, can be monitored by placing a small magnet on the latch and measuring the magnetic field intensity at a suitable location fixed with respect to the seat belt buckle. The sensor within integrated circuit package is mounted to a fixed portion of a latch follower spring support, which also encloses the guide plate of the latch. Therefore, the magnet is moved along with the latch to be cooperated with the sensor.

Another typical technology is disclosed in U.S. Pat. No. 6,076,239 (Jun. 20, 2000), which is related to a seat belt buckle with slide sensor. The seat belt buckle comprises a belt lock for a safety belt that includes a frame, a latching element for the latching of the belt tongue and a securing element, which secures the latching element in the latched state. A detector device is provided at the belt lock which detects the position of the securing element. The detector device has a hall probe and a magnet secured to the securing element. The hall probe and the magnet only lie close to and opposite one another when the securing element is located in its closed end position. Therefore, the detector device detects the position of the securing element.

But, these seat belt buckles include only one non-contact switch. For it, it has a disadvantage in being not usable for various purposes. Especially, it must sacrifice the feature of quickly warning the non-wearing of a seatbelt to an occupant in using a contact switch or of applying a control signal to an electronic control unit for a self-diagnostic function in using a non-contact switch. Therefore, it is preferable if the advantages of the contact and non-contact switches are used.

In order to use these advantages, to a seatbelt buckle disclosed in European Patent Application EP1088037A2, a locking state detecting apparatus of a vehicle's buckle detected in European Patent Application EP107882A1 can be adapted as follows:

The seatbelt buckle includes a body frame, a release button slidably coupled to the body frame for unlatching a seatbelt tongue from the seatbelt buckle, a locking lever capable of being pivotally rotated about wings by a predetermined angle, a slider for supporting and fixing the locking lever and an ejector for pushing the tongue in a longitudinal direction which is a lengthwise direction of the body frame. The body frame has an arch-shaped supporting beam which is integrally formed with the body frame in a manner such that the supporting beam is elected in a vertical direction. The supporting beam serves to limit movement of the slider and increase structural rigidity of the seatbelt of the seatbelt buckle. The slider has a width, which is greater than that of the body frame, and possesses shock-absorbing means for increasing durability of the seatbelt buckle. The release button has at least two release projections, which are formed with inclined surfaces that are in turn brought into contact with the inclined projections of the sliders.

In the seatbelt buckle, there may be mounted a locking state detecting apparatus of EP107882A1, in which a contact switch and a non-contact switch are mounted on the inner right and left surfaces of the seatbelt buckle, respectively, adjacent to both sides of the body frame.

The seatbelt buckle is positioned in a lower case so that the tongue inserted is not escaped therefrom. For example, as the tongue is pushed into an inserting opening formed in the body frame, an ejector mounted in a slidably opening of a bottom plate is moved rearward. A locking lever, which is positioned on an upper end of the body frame and elastically supported by a spring, is rotated downward about wings to let a latch bar to be locked to the tongue.

At that time, the ejector forces ends projected from its both sides and out of the body frame to operate the contact and non-contact switches at once. The contact switch such as a micro-switch called “mechanical switch” is turned on to interrupt a power source applied to a warning lamp, so it means that the non-wearing of a seat belt is not warned for occupants. The non-contact switch such as a multi-purpose buckle sensor assembly including a hall sensor and a permanent magnet is operated to detect the insertion of the tongue according to the approaching of the permanent close thereto, so that it supplies detecting signals to an electronic control unit (ECU) constituted as part of a vehicle control portion to perform the self-diagnostic function.

Nevertheless, the configuration shows that the contact and non-contact switches are mounted in the lower case to be separated from each other and their corresponding wirings are separated from each other. For it, their mounting is not easy and additional space for their mounting is required. t is difficult to mount the contact and non-contact switches at one place with a good space efficiency and operate them cooperating with the buckle.

Therefore, the configuration causes the contact and non-contact switches to have different operating time points, so it can't make an expression that they are operated with the buckle assembly at the same time. The configuration is not proper for a multi-purpose buckle sensor assembly to which the invention is adapted, which is integrated into one unit. Herein, it is noted that the unified multi-purpose buckle sensor assembly enhances the self-diagnostic function of the electronic control unit in a vehicle.

SUMMARY OF THE INVENTION

Accordingly, an object of the invention is to provide a multi-purpose buckle sensor assembly including a contact switch and a non-contact switch integrated into one unit to detect the locking or unlocking state of a buckle assembly.

Other object of the invention is to provide a multi-purpose buckle sensor assembly including a contact switch and a non-contact switch integrated into one unit to control a warning lamp, quickly, and generate a control signal of an electronic control unit according to the locking or unlocking state of a buckle assembly at the same time.

Another object of the invention is to provide a multi-purpose buckle sensor assembly including a contact switch and a non-contact switch integrated into one unit to generate at least one control signal and to be used for multi-purpose according to the locking or unlocking state of a buckle assembly

According to the invention, a buckle assembly comprises an upper case, a lower cases coupled with the upper case and including a position determining projection for determining the position of a multi-purpose buckle sensor assembly, ribs for supporting the front portion of the multi-purpose buckle sensor assembly and first and second supporting blocks each positioned on the front portion of a terminal block and inserted in a groove portion of the terminal block, a release button coupled to the frame for unlatching a locking bar of a locking lever from a tongue, an ejector elastically and movably supported in a sliding aperture for discharging the tongue latched to a locking bar of a locking lever out of outside responsive to the release button, the locking lever including a slider elastically and movably mounted on a guide surface thereof and for being pivoted at one end portion and latching or unlatching the tongue at the other end portion, a frame including a coupling groove for determining the position to be coupled with the multi-purpose buckle sensor assembly and a coupling surface to be engaged with a hook portion of a base plate and for supporting the ejector on a bottom thereof, supporting the slider against the inner upper surface of an arched supporting beam thereof and pivotally rotating the locking lever at its rear end, in which:

a multi-purpose buckle sensor assembly comprises a hall sensor portion including a hall sensor and a printed circuit board electrically connected to each other which are enclosed in one package, a base plate electrical connected at one end portion to the printed circuit board and at the other end to a cable having control lines and power lines and a supporting plate integrated on the upper surface thereof, a movable member freely moving on the base plate and including a first permanent magnet mounted at its center portion and a pair of contact terminals contacted with the metal pattern and a terminal block including the control lines and power lines contained therein and means for determining the position of the multi-purpose buckle sensor assembly and fixing it in the lower case; the lower case including means for determining the position of the multi-purpose buckle sensor assembly and fixing it thereon; the frame including means for determining the position of the multi-purpose buckle sensor assembly and fixing it thereto; and a second permanent magnet mounted on the center of the ejector to be cooperated with the hall sensor.

DETAILED DESCRIPTION OF THE INVENTION

Referring toFIG. 1, a seatbelt buckle apparatus100includes an upper case1and a lower case2containing a buckle assembly and a multi-purpose buckle sensor assembly therein, which are coupled to each other

The lower case2receives the buckle assembly which includes a release button3fixed to a frame4, an ejector5slidably mounted on a bottom plate of the frame4, a locking lever6pivotally mounted on the upper portion of frame side walls to be coupled with a tongue and a slider7movably mounted on the locking lever6, which are integrally assembled into each another.

First, the multi-purpose buckle sensor assembly10will be explained for the purpose of helping the understanding of the invention. The multi-purpose buckle sensor assembly10includes a hall sensor portion11packaged with a hall sensor and a printed circuit board, a base plate12including a metal pattern23in a predetermined form fixed thereon and having a good electric conduction, a movable member13movably mounted on the base plate12with a pair of contact terminals being mounted on its lower surface to be contacted with the metal pattern and a terminal block14having control lines and power lines electrically coupled through the metal pattern to the base plate12.

As shown inFIG. 3, the hall sensor portion11includes a hall sensor21and a printed circuit board22having an electrical circuit connected with the hall sensor21, which are enclosed in one package. When the hall sensor21is cooperated with a permanent magnet to generate control signals, the control signals are applied to at least one predetermined terminal of the metal pattern23connected to the printed circuit board22and then through a cable15having at least one control line to an electronic control unit. The power lines16are for positive and negative voltages to be supplied to a system, the power of which is used to lighten or put out a warning lamp mounted on an instrument panel according to the movement of the movable member13on the metal pattern23.

The base plate12includes the metal pattern23and a supporting plate24, in which the metal pattern23includes terminal portions A, B, C, D, E and F respectively patterned in a predetermined shape. The terminal portions A and F are for a positive power source (+) and a negative power source and the terminal portions B, C, D and E are for a control signal of the electronic control unit, for example the terminal portion E corresponding to ground and other terminal portions corresponding to control signal terminals. Besides, a dotted line I-I′ is cut after the metal pattern23is fixed to the supporting plate24and the terminal portions A˜F are connected to the connecting end of the control lines and power lines. The supporting plate24includes power terminal seats25and control terminal seats26formed adjacent a terminal block14, to which the connecting ends of the control lines and the power lines are electrically coupled along with the terminal portions A˜F, selectively. Hook portion27are integrally projected from both front side surfaces of the supporting plate28adjacent the all sensor portion13, and positioning members27are integrally projected from the supporting plate24facing to both rear side surfaces of the control terminal portions B˜E, so that the base plate12is fixed to the lower surface of the frame4.

The movable member13includes a first permanent magnet31mounted at its center, a pair of contact terminals32mounted on its lower surface opposite the metal pattern23, a groove portion33formed adjacent both sides thereof, into which a pair of leg portions of the ejector5are fitted, and a guider34formed to allow the movable member13to be moved on the base plate12. Therefore, the movable member13enables the cooperating of the hall sensor21with the first permanent magnet31as well as the selection of the contact terminals32to predetermined terminals of the metal pattern24. Therefore, the hall sensor21generates control signals for the electronic control unit, and the contact terminals32perform the supply or interruption of the power to the warning lamp.

The terminal block14is configured to have upper and lower portions forming a hollow at its center, which are made of a heat-melted material at a lower temperature, and heat-molded along with the cable15and the power lines16contained therein. The terminal block14is made in the form of a fork having three branches at the front portion. A middle portion17is enclosed containing the connecting ends of the control lines and the control terminal portions B˜E connected to each another, which are positioned in the corresponding power terminal seats26. Both projecting portions18constituted as outer branches are enclosed containing the connecting ends of the power lines and the power terminal portions A and F connected to each another, which are in the corresponding terminal seats25. The projecting portion18is horizontally projected at the approximate middle portion of the terminal block14in a lengthwise and then extended forward. Therefore, between the middle portion17and the projecting portion18there is formed a space in the form of a groove. The hook portion27is positioned in the space to form a hole19for determining the mounting position of the multi-purpose buckle sensor assembly10. The terminal block14also includes extensions20extended from both rear sides thereof to form a groove portion20′ for coupling with the multi-purpose buckle sensor assembly10.

As shown inFIGS. 4 and 5, the multi-purpose buckle sensor assembly10is constructed to assemble other parts on the base plate12. In other words, the base plate12is constructed to fix the metal pattern23to the supporting plate24. Before preceding this work, the printed circuit board22is electrically connected to the metal pattern23in a predetermined electric arrangement, and then the hall sensor21is electrically coupled to the printed circuit board22to establish a predetermined control circuit. Thereafter, the hall sensor21is made into one unit with the printed circuit board22using coupling holes21′ and22′ in one package form. The dotted line I-I′ is cut out. The terminal block14is enclosed and heat-treated for its shape containing the connecting ends of the control lines and the power lines and the control along with the terminal portions A˜F connected to one another, which are positioned in the corresponding power terminal seats26.

Referring toFIG. 1, again, the upper case1is opened at its front surface and includes sidewalls35extended downward from the upper portion thereof. Clamps36, a first supporting end portion37and a second supporting end portion38are formed projecting from the front, middle and rear of the sidewalls35. A hook insert groove39is formed on the inner surface of the sidewalls35.

The lower case2is constructed to force the multi-purpose buckle sensor assembly10to be positioned and received therein. A front wall41has a space (called “insertion opening” below) between a release button and it for the insertion of a tongue and clamp grooves43formed in corner portions adjacent the front wall for the fitting of the clamp36thereinto. Both sidewalls42includes first and second supporting grooves44and45respectively formed on the thickness thereof at the middle and rear ends corresponding to the first and second supporting end portions37and38. A hook-fixing portion46is integrated on inner surfaces of both sidewalls42between the first and second supporting grooves44and45to be engaged with the hook grooves39, respectively. The hook-fixing portion46includes a hook47positioned to have a height a little higher the sidewalls42at the upper end and a plurality of ribs48extended toward the inner portion of the lower case2to have at least one different width from each another in a group. A first supporting block49is integrally extended on a bottom50from the approximate middle portion of the sidewalls42to be positioned at the front surface of the terminal blocks14and contacted with the side of the base plate12. The second supporting block51is extended on the bottom50from a pair of rib48having a smaller width to be fitted into the groove portion19. The first and second supporting blocks49and51have a height equal to that of the terminal block14in the form of a rectangular body to reinforce the sidewalls42and the bottom50.

On the bottom50, a position determining projection53is formed between the first and second supporting blocks49and51to be fitted into the hole19, which determines the mounting position of the multi-purpose buckle sensor assembly10and prevents its rocking. Guide walls52are formed behind the second supporting block51on the bottom50in an arc shape to be opposite to each other. A shoulder54having a little wider area is formed below the position determining projection53to support the base plate12contacting therewith.

Therefore, as shown inFIG. 2, when the upper case1is coupled with the lower case2, the multi-purpose buckle sensor assembly10is first positioned on the bottom50. The multi-purpose buckle sensor assembly10is positioned by the reference of the position determining projection53in a manner that the position determining projection53is fitted into the hole19of the terminal block14and its shoulder54is contacted with the lower surface of the base plate12to secure a predetermined gap between the bottom50and the base plate12. At that time, the front end of the hall sensor portion14is supported contacting with the reinforcing ribs55. The first supporting block49supports the base plate12contacting with both side surfaces of the base plate12adjacent the front-end portion of the terminal block14, and the second supporting block51supports the terminal block14with its front end portion being fitted into the groove. The control line cable15and power lines16connected to the terminal block44extend outside passing through the guide walls52.

Additionally, the lower case2is coupled with the upper case10after the buckle assembly is coupled with the multi-purpose buckle sensor assembly10to be cooperated with each other. For example, the clamp13is inserted into the clamp groove43, and the first and second supporting end portions37and38are respectively contacted with the first and second supporting grooves44and45to be corresponded to each other. Next, the hook-fixing portion46serves to couple the lower case2with the upper case1in a manner that the first and second supporting end portions44and45are fitted into the first and second supporting grooves44and45.

Returning toFIG. 1, the frame4is made of single metal plate materials and easily manufactured by a press processing, which is coupled with the release button3. The frame4includes a hook portion62projected forward from the front portion of a lower plate61, an arched supporting beam63vertically elected at the front portion, upstanding side walls64projected from both side ends thereof. The arched supporting beam63includes an opening at the center of its front surface, a first projecting piece66projected from the upper center thereof and a guide jaw67extended and bent downward from its front portion to guide the tongue thereinto. The release button3is coupled with the frame4in a manner that a first spring68is inserted onto the first projecting piece66at one end, and a hook of the hook portion62is passed through the guider3′ to allow the release button3to be moved on the hook portion62.

The lower plate61includes a sliding aperture69formed to move the ejector5along the lengthwise portion thereof and coupling hole65for mounting a connector70(referring toFIG. 6) therein by an anchor. A second projecting piece63is projected inward from the rear portion of the sliding aperture69, and a coupling surface74is formed adjacent the rear portion of the sliding aperture69to be coupled with the hook27of the multi-purpose buckle sensor assembly10.

The upstanding walls64include a stopper groove75and a hinge groove76formed at the rear portion of its upper portion, in which a hinge projection77is projected inward from the hinge groove78(referring to FIG.6). A coupling groove78is formed behind the hook portion62on the bottom50to prevent the front portion of the multi-purpose buckle sensor assembly10from being rocked.

The ejector5includes a guiding groove81formed on both side surfaces to allow a part of a lower plate61adjacent the sliding aperture69to be inserted thereinto, a contacting portion formed as a front surface in an arc shape to be contacted with a tongue and two separation-preventing portions83projected out of the front surface thereof to prevent the separating of the tongue contacted corresponding to the contacting portion82. A receiving portion74is formed at the rear portion of the ejector5to receive the other end of the second spring72elastically supported in the sliding aperture69. A second permanent magnet85is mounted on the center to cooperate with the hall sensor of the hall sensor portion11. A pair of leg portions86is formed on the lower surface of the ejector5adjacent both guide grooves81, which are fitted into the groove portions33to force the movable member13to be moved on the base plate12according to the movement of the movable member13.

The locking lever6includes a coupling surface91coupling with the upper rear surface of the arched supporting beam63, from the center of which a bending portion92is projected downward. A locking bar93is extended downward more than the bending portion92enough to be coupled with the tongue inserted into the insertion opening of the arched supporting beam63. A guide surface94is extended rearward from the coupling surface91to formed both side surfaces of the locking lever6and enable the slider7to be moved thereon. A stopper95and a hinge portion96are formed on the rear portion of the locking lever6to be respectively coupled into the stopper groove75and the hinge groove76. An aperture is formed behind the guide surface94to mount a third spring98therein with one end being inserted into a third projecting piece97. The third spring98is arranged on the aperture with the other end being coupled to the slider7.

The slider7includes a guide rail87formed on the lower surface thereof to be movably inserted onto both end portion of the guide surface94and a fixing piece88formed on the rear portion thereof to be fixed to the other end of the third spring98. The slider7is positioned on the guide surface94with the guide rail87being inserted into both side ends thereof and the third spring98elastically supporting the slider7between the third projecting piece93and the fixing piece92. At that time, the slider7is contacted at the coupling surface89with the upper rear surface of the arched supporting beam63in an initial assembling state. The slider7further includes a hooked hanger90and is moved rearward along the guide surface94upon the backward motion of the ejector5. At the same time the hooked hanger90is moved downward with being hung on the front surface of the arched supporting beam63, so that the coupling surface89is introduced into the aperture of the arched supporting beam63.

On the other hand, the buckle assembly is assembled as follows: the ejector5is assembled to be electrically supported in the sliding aperture69, whereby the guide grooves81are fitted into the lower plate61adjacent the sliding aperture69and the second spring72is arranged at one end to be coupled into the receiving portion84and at other end to be fitted into the second projecting piece73.

Next, the slider7is assembled on the locking lever6in a manner to movably mount the guide rail87onto the side end portion of the guide surface94with the third spring98being elastically arranged between the fixing piece88and the third projecting piece93. The locking lever6is mounted on the upper portion of the frame4so that the stopper95is inserted into the stopper groove75to prevent the advance thereof, and the hinge portion96is seated in the hinge groove76to pivotally rotate the locking lever6downward or upward about it. At that time, the hinge projection77prevents the accidental separation of the locking lever6out of the hinge groove66.

In order to mount the buckle assembly over the multi-purpose buckle sensor assembly40by the reference of the positioning member27, the positioning member29is fitted into the coupling groove78and the leg portions81are coupled into the groove portions34, respectively. The hook member28is engaged with the coupling surface74on the rear portion of the sliding aperture69on the lower plate61. So, the multi-purpose buckle sensor assembly10and the buckle assembly are mounted at the same time in the lower case2.

As shown inFIGS. 4A and 4B, in the lower case20, a multi-purpose buckle sensor assembly10is mounted on the bottom61so that a position determining projection53determines its mounting position by being fitted into a hole19, a first supporting block49supports a base plate12and a second supporting block50supports a terminal block14. A cable15having control lines and power lines are arranged between guide walls52to pass therethrough.

The buckle sensor assembly is associated with the multi-purpose buckle sensor assembly10for their simultaneous operating. A guide jaw67is placed on the inner upper portion of a front wall41. A positioning member27is fitted into a coupling groove78(referring to FIG.1), a coupling surface74is engaged with a hook portion28and a connector8placed on a coupling hole65is fixed a bottom61by an anchor to mount the buckle assembly in a vehicle. An ejector5is mounted in a sliding69so that a pair of leg portion76is respectively fitted into groove portions46to reciprocate a movable member13on a base plate12.

Herein, it is noted that a first permanent magnet31leads to the operating of a hall sensor in a ball sensor portion11according to the movement of the movable member13, so that a pair of contact terminals32selects predetermined terminals of a metal pattern to lighten or put out a warning lamp mounted on an instrument panel. An elector5includes a second permanent magnet85at the center thereof, which is placed close to the hall sensor of the ball sensor portion11at an initial position along with a first permanent magnet31.

Therefore, as shown inFIG. 6A, the buckle assembly is coupled with the multi-purpose buckle sensor assembly10at first state, so that the first and second permanent magnets31and85are placed adjacent the hall sensor portion11. In that case, a pair of contact terminal32forces a power source of power lines16to be applied to the warning lamp based on the metal pattern23, thereby lightening it and warning the non-wearing of a seatbelt to occupants. At the same time, the hall sensor generates control signals to apply them through a cable15to an electronic control unit, so that other safety apparatuses such as an airbag system, etc. stand ready for corresponding safety operating.

As shown inFIG. 6B, as a tongue1is inserted into an insertion opening over a front wall41, the ejector5is moved backward along with the movable member13. The locking lever6is moved downward at the front-end portion thereof to insert the opening of the arched supporting beam63. And then a locking bar93is inserted into a center aperture of the tongue9to lock it to the buckle assembly. Therefore, the first and second permanent magnets31and85are placed adjacent the hall sensor portion11. Therefore, the first and second permanent magnets31and85are placed away from the hall sensor portion11. The hall sensor21generates another control signal to apply them through the cable15to the electronic control unit based on the metal pattern23, so that other safety apparatuses such as an airbag system, etc. release the stand by state for corresponding safety operating. At the same time, the power source of the power line16is interrupted to put out the warning lamp, which represent the wearing of the seatbelt.

As described above, the invention enables the mounting of a multi-purpose buckle sensor assembly in a case to enhance the space efficiency, and the operations of contact and non-contact switches happens simultaneously cooperating with each other.