JP2011098668A - State detection device and buckle device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a state detection device which does not require to consider the influence of over-stroke even when a tongue plate is overstroked from a state where the tongue plate is inserted to a buckle body and held, and to provide a buckle device using the same. <P>SOLUTION: The buckle device includes a device body and a buckle switch 2. The buckle switch 2 includes, a housing 201 which is a casing, a slide portion 202 which is supported by the housing 201 to be linearly movable, a magnet 203 which is a permanent magnet which linearly moves in linking with the slide portion 202, a spring 205 for over-stroke which is a first elastic member interposed between the slide portion 202 and the magnet 203, a spring 204 for over-stroke which is a second elastic member interposed between the magnet 203 and the housing 201, and an MR sensor 210 serving as a magnetic detector for detecting the change of magnetic flux density from the magnet 203. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a state detection device and a buckle device using the same.

  The vehicle is provided with a seat belt device for restraining the seated occupant's body for safety. The webbing pulled out from the webbing take-up device of the seat belt device passes through a slit-like insertion hole formed in a through anchor provided above the center pillar of the vehicle, and is folded back to the vehicle lower side. It is fixed to an anchor provided in the vicinity of the winding device. Further, a tongue is provided on the webbing between the tip of the webbing fixed to the anchor and the folded part of the through anchor. The tongue plate of the tongue restrains the occupant's body by being inserted and held in the apparatus body of the buckle device.

  Here, the buckle device is provided with a state detection device for detecting that the tongue plate is inserted and held in the device main body. This state detection device detects a slide position state of the tongue plate in the buckle body, and is called a buckle switch. For example, the buckle body is provided with a printed circuit board on which first and second switch circuits having Hall ICs are mounted, and a slider to which a magnet facing the first and second switch circuits in contact or non-contact is attached. When the tongue plate is inserted into the buckle, the slider is pushed inward by the tongue plate and the slider moves inwardly. After the magnet is in contact with or close to the second switch circuit, the tongue plate is moved close to the first switch circuit. There is a buckle device including a state detection device configured to be latched by a buckle (see, for example, Patent Document 1).

  According to this buckle device, it is said that the operation from the state before the tongue plate is inserted into the buckle body to the state after the latching during the insertion and the operation after the latching can be reliably detected. .

JP 2001-260817 A

  However, in the buckle device shown above, when the tongue plate is inserted and held in the buckle body and overstroke, the amount of sliding of the magnet increases, and there is a concern that the output is reversed or the magnetic flux density is lowered. For this reason, there existed a problem that the size of a magnet had to be set large, and there existed a problem that there existed a restriction | limiting in the small size and weight reduction of a buckle apparatus.

  Therefore, an object of the present invention is to provide a state detection device and a buckle device using the state detection device that do not have to consider this effect even if the tongue plate is inserted and held in the buckle body and overstroke. It is in.

  [1] In order to achieve the above object, the present invention provides a housing, a slide portion movably supported by the housing, a permanent magnet that moves in conjunction with the slide portion, the slide portion, A first elastic member interposed between the permanent magnets; a second elastic member interposed between the permanent magnets and the housing; and a magnetic detector for detecting a change in magnetic flux density from the permanent magnets. The state detection apparatus characterized by the above is provided.

  [2] The state detection device according to [1], wherein the rigidity of the first elastic member is larger than the rigidity of the second elastic member.

  [3] The state detection device according to [1], wherein the casing includes a contact portion that defines a stop position of the permanent magnet that moves in conjunction with the slide portion. Good.

  [4] In order to achieve the above object, the present invention provides an apparatus main body capable of inserting and holding a tongue plate provided on a webbing of a vehicle seat belt apparatus, and the above [1] mounted in the apparatus main body. To a state detecting device according to any one of [3], and a buckle device.

  [5] In order to achieve the above object, the present invention is a device main body capable of inserting and holding a tongue plate provided on a webbing of a seat belt device of a vehicle, and is movably supported in the device main body. A sliding portion, a permanent magnet that moves in conjunction with the sliding portion, a first elastic member that is interposed between the sliding portion and the permanent magnet, and a second elasticity that is interposed between the permanent magnet and the apparatus main body. A buckle device comprising: a member; a third elastic member interposed between the slide portion and the apparatus main body; and a magnetic detector for detecting a change in magnetic flux density from the permanent magnet. .

  [6] The state detection device according to [5], wherein the rigidity of the third elastic member is larger than the rigidity of the first elastic member and the second elastic member.

  [7] The buckle device according to [5], wherein the housing includes a contact portion that defines a stop position of the permanent magnet that moves in conjunction with the slide portion. Also good.

  According to one aspect of the present invention, there is provided a state detection device and a buckle device using the state detection device that do not have to consider this influence even if the tongue plate is inserted and held in the buckle body and overstroke. be able to.

FIG. 1 is an exploded perspective view of a buckle device according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the buckle device showing a state before the tongue plate is inserted into the buckle body. FIG. 3A is a cross-sectional view of the state detection device showing the state before the tongue plate is inserted into the buckle body, and FIG. 3B is the state where the tongue plate is inserted into the buckle body and the magnet slides to the lock position. It is sectional drawing of the state detection apparatus which shows the state which carried out, (c) is sectional drawing of the state detection apparatus which shows the state which the slide part overstroked. FIG. 4 is a cross-sectional view of the buckle device showing a state after the tongue plate is inserted into the buckle body. FIG. 5 is a diagram showing the relationship between the direction of the magnetic field and the output value of the MR sensor. FIG. 6 is a characteristic diagram showing the relationship between the magnet slide amount S and the output voltage V. FIG.

(Embodiment of the present invention)
FIG. 1 is an exploded perspective view of a buckle device 1 according to an embodiment of the present invention. The buckle device 1 is a device main body capable of inserting and holding a tongue plate 130 provided on a webbing of a seat belt device of a vehicle, and a state detection device that is arranged in the device main body and detects a state of a slide position. A buckle switch 2. The buckle switch 2 includes a housing 201 that is a housing, a slide portion 202 that is movably supported by the housing 201, a magnet 203 that is a permanent magnet that moves in conjunction with the slide portion 202, a slide portion 202, and a magnet. The change in magnetic flux density from the overstroke spring 205 as the first elastic member interposed between the 203, the stroke spring 204 as the second elastic member interposed between the magnet 203 and the housing 201, and the magnet 203 And an MR sensor 210 as a magnetic detector for detection.

  FIG. 2 is a cross-sectional view of the buckle device 1 showing a state before the tongue plate is inserted into the buckle body. The buckle device 1 includes a case 14 that constitutes the device body. The case 14 is a box-shaped cylindrical member that is open at both ends in the longitudinal direction, the opening at one end in the longitudinal direction is an anchor insertion port 16, and the opening at the other end in the longitudinal direction is a tongue insertion port 18. Yes. A base 20 that constitutes the main body of the apparatus together with the case is housed inside the case 14.

  As shown in FIGS. 1 and 2, the base 20 includes a flat bottom plate 22 that is elongated along the longitudinal direction of the case 14. A substantially plate-like anchor plate 24 as an anchor member is superposed on one end side in the longitudinal direction of the bottom plate 22, and the bottom plate 22 and the anchor plate 24 are mechanically connected by a rivet (not shown). The other end of the anchor plate 24 is fixed to the vehicle body (not shown) at the side of the vehicle seat, and the buckle device 1 is attached to the vehicle.

  On the other hand, side walls 32 are erected from both ends in the width direction of the bottom plate 22 in the thickness direction of the bottom plate 22, and ejectors 34 as moving bodies are disposed between the side walls 32. A part of the ejector 34 is engaged with a guide hole 36 formed in the bottom plate 22, and can slide within a predetermined range along the guide hole 36 in the longitudinal direction of the bottom plate 22. The ejector 34 is urged from the housing 201 side toward the other end in the longitudinal direction of the bottom plate 22 via an ejector spring 206 as a third elastic member.

  Further, the buckle switch 2 is attached to the bottom plate 22, and as shown in FIG. 2, the end face of the slide portion 202 located on the opening side of the housing 201 is attached in a state of being in contact with the pressing projection 34a of the ejector 34. It has been. Therefore, the ejector 34 is urged toward the other end in the longitudinal direction of the bottom plate 22 by the stroke spring 204, the overstroke spring 205, and the ejector spring 206.

  FIG. 3A is a cross-sectional view of the buckle switch 2 showing a state before the tongue plate 130 is inserted into the buckle body. The buckle device 1 includes a buckle switch 2 as a state detection device. The buckle switch 2 includes a housing 201 as a housing, a slide portion 202 supported by the housing 201 so as to be linearly movable, a magnet 203 that is a permanent magnet that moves linearly in conjunction with the slide portion 202, a slide Over-stroke spring 205 as a first elastic member interposed between portion 202 and magnet 203, stroke spring 204 as a second elastic member interposed between magnet 203 and housing 201, and magnetic flux density from magnet 203 An MR sensor 210 serving as a magnetic detector for detecting a change is included.

  The housing 201 is made of, for example, a nonmagnetic material such as resin. It has a cylindrical shape such as a cylinder or square tube having an opening 201a at one end, and a slide portion 202 and a magnet 203 are slidably accommodated in the inner space. A stroke spring 204 is disposed in an extended state between the magnet 203 and the bottom 201b of the housing 201, and an overstroke spring 205 is disposed in an extended state between the magnet 203 and the slide portion 202. .

  The housing 201 serves as an abutting portion on which a magnet 203 slides and moves in the direction of the bottom 201b of the inner space when the tongue plate 130 described later is inserted and held in the buckle device 1. The contact surface 201c is provided. The contact surface 201c defines a stop position of the magnet 203 when the tongue plate 130 is inserted and held in the buckle device 1. Therefore, even if the slide portion 202 overstrokes due to the insertion of the tongue plate 130, the magnet 203 does not overstroke.

Here, the stroke spring 204, the overstroke spring 205, and the ejector spring 206 are all coil springs, and their spring constants K ₁ , K ₂ , and K ₃ are, for example, K ₁ <K ₂ <<are formed so as to satisfy the condition of K _3. In addition, since the magnet 203 is arrange | positioned in the vicinity, it is preferable to use nonmagnetic materials, such as austenitic stainless steel. It is also possible to use an elastic member such as rubber other than the coil spring described above.

Until the tongue plate 130 is inserted into the buckle device 1 and the end of the magnet 203 comes into contact with the contact surface 201c (sliding amount = L), the ejector spring 206 is compressed and the stroke spring 204 and overload The stroke spring 205 is compressed. As described above, since these spring constants are set to K ₁ << K ₂ << K ₃ , the operating force when inserting the tongue plate is dominated by the spring constant K ₃ , and the operational feeling is the same as before. Absent. In addition, after the end of the magnet 203 comes into contact with the contact surface 201c, only the overstroke spring 205 is compressed by the overstroke of the slide portion 202 (the slide amount of the slide portion 202> L).

  As the magnet 203, various permanent magnets such as ferrite, rare earth, and neodymium can be used. Moreover, the outer periphery can be coat | covered with a resin mold. In order to detect the movement of the tongue plate 130, the magnet 203 gives a change in magnetic flux density to a magnetic detector disposed in the vicinity by a magnetic field change of the magnet 203 in conjunction with the movement of the tongue plate 130 and the slide portion 202. The magnetization direction can be either a sliding direction or a direction orthogonal thereto, but in this embodiment, as shown in FIG. 3A, the magnetization direction is in the sliding direction, that is, the left-right direction. Is set.

  If the tongue plate 130 is inserted into the buckle device 1 and the end of the magnet 203 abuts against the abutment surface 201c, the buckle attachment operation is performed. Thus, the MR sensor 210 is mounted.

  The MR sensor 210 detects a change in the direction of a magnetic field or a change in magnetic flux density. The MR sensor 210 changes its resistance value due to a change in the magnetic field in the surface direction of the resistance chip constituting the MR sensor. Accordingly, as shown in FIGS. 1 to 3 and the like, in a state in which the MR sensor 210 is mounted on the substrate 211, the substrate is arranged so that the magnetic flux of the magnet 203 crosses the resistance chip inside the MR sensor 210 mainly in the surface direction. Arranged upright.

  The positional relationship between the MR sensor 210 and the magnet 203 is shown in FIGS. As shown in FIG. 2, before the tongue plate 130 is inserted into the buckle device 1, that is, when the slide portion 202 is positioned on the opening 201 a side of the housing 201, one end (N pole) of the magnet 203 is The MR sensor 210 is disposed substantially below. On the other hand, in the state where the tongue plate 130 is inserted into the buckle device 1 and the buckle mounting operation is completed, that is, in the state where the magnet 203 is in contact with the contact surface 201c in the housing 201, as shown in FIG. The MR sensor 210 is positioned substantially below the other end 203 (S pole) of 203.

  FIG. 5 is a diagram showing the relationship between the direction of the magnetic field and the output value of the MR sensor. When the MR sensor 210 is arranged in the positional relationship as described above, when the buckle is not attached, as shown in FIG. It is a value. On the other hand, when the buckle is mounted with the tongue plate 130 inserted into the buckle device 1, the magnetic field is directed obliquely upward to the left with respect to the MR sensor 210, and the output of the MR sensor exhibits a maximum value. As a result, the output voltage of the MR sensor 210 can be changed, for example, from a minimum value to a maximum value, and the state of the slide position, that is, the buckle mounting and the buckle non-mounting can be accurately determined.

  In addition to MR sensors, for example, GMR (Giant Magneto Resistance) can be used as a magnetic detector. As shown in FIG. 2 and the like, the MR sensor 210 is attached to the case 14 while being mounted on the substrate 211. However, the MR sensor 210 may be attached to the bottom plate 22 in addition to the case 14, for example. . Further, it may be attached to the housing 201 of the buckle switch 2, and in this case, the housing 201 is provided with a magnet 203 as a detection target and an MR sensor 210 as a detector, thereby constituting a completed detector unit. can do.

  Here, as shown in FIG. 1, the tongue plate 130 is inserted between the side walls 32 from the other end in the longitudinal direction of the bottom plate 22. The tongue plate 130 includes a base portion 132 formed of a metal plate material. The base portion 132 is formed with a slit hole 134 that is long along the opposite direction of the side wall 32 with the tongue plate 130 inserted between the side walls 32, and is a middle portion in the longitudinal direction of the long belt-like webbing belt 140. Is inserted.

  The webbing belt 140 is locked at its base end to a take-up shaft of a webbing take-up device (not shown), and is wound up by a spiral coil spring or the like for urging the take-up shaft in the direction of winding the webbing belt 140. The housing urging force of the shaft urging means acts on the webbing belt 140.

  Further, an insertion plate portion 136 is formed on the base portion 132. The width of the insertion plate portion 136 is smaller than the interval between the side walls 32, and the insertion plate portion 136 of the tongue plate 130 is actually inserted between the side walls 32 (see FIG. 4).

  A through-hole 138 that penetrates in the thickness direction is formed in the insertion plate portion 136. When the insertion plate portion 136 reaches a predetermined position on one end side in the longitudinal direction of the bottom plate 22 between the side walls 32, a latch described later 50 engagement pieces 58 can be penetrated, and the engagement pieces 58 penetrate through the through holes 138, whereby the extraction of the tongue plate 130 from the buckle device 1 is regulated.

  On the other hand, as shown in FIGS. 1, 2, and 4, the buckle device 1 includes a latch 50. The latch 50 includes a base 52. Although it depends on the posture of the latch 50, the base 52 is formed in a flat plate shape that is generally longitudinal in the opposing direction of the side walls 32 and in the thickness direction along the longitudinal direction of the bottom plate 22. Both end portions in the direction enter into support holes 54 as support portions formed on both side walls 32. The base 52 (that is, the latch 50) is supported so as to be rotatable by a predetermined angle with the longitudinal direction of the base 52 as an axial direction until it is interfered with the inner peripheral portion of the support hole 54.

  Further, a flat plate-like connecting portion 56 extends from one end in the width direction of the base portion 52 in the longitudinal direction toward one side in the width direction of the base portion 52, and further, the connecting portion on the opposite side to the base portion 52. An engaging piece 58 extends from 56 toward the bottom plate 22 side.

  The front end 58a of the engagement piece 58 corresponds to the through hole 60 formed in the bottom plate 22, and when the latch 50 is displaced, the engagement piece 58 is changed to the through hole 60 as shown in FIG. I can get in.

  As shown in FIGS. 1, 2, and 4, the thickness of one side (opposite to the bottom plate 22) of the ejector 34 described above corresponding to the tip of the engagement piece 58 of the latch 50 is A mounting piece 62 is provided integrally. As described above, the urging force from the stroke spring 204, the overstroke spring 205, and the ejector spring 206 of the buckle switch 2 acts on the ejector 34.

  In the thickness direction of the bottom plate 22 in a state where the ejector 34 is located at a position where no external force other than the urging force from the stroke spring 204, the overstroke spring 205, and the ejector spring 206 is acting. A placement piece 62 is provided so as to face the tip of the engagement piece 58 along the edge. As shown in FIG. 4, the placement piece 62 interferes with the distal end portion of the engagement piece 58 in a state of facing the distal end portion of the engagement piece 58, and the engagement piece 58 moves in a direction approaching the bottom plate 22 ( That is, the movement of the latch 50) is restricted.

  Further, stoppers 64 are extended from both ends in the longitudinal direction of the base 52. The stopper 64 is formed so that the tip side is positioned on the slide locus of the ejector 34 against the urging force of the stroke spring 204, the overstroke spring 205 and the ejector spring 206. When the ejector 34 slides a predetermined distance against the biasing force of the spring 205 for ejector and the spring 206 for ejector, the ejector 34 contacts the stopper 64.

  Further, a lock member 70 is disposed on the opposite side of the base 20 from the bottom plate 22 via the connecting portion 56 of the latch 50. The lock member 70 includes a base 72. The base 72 has a substantially square bar shape that is formed in the longitudinal direction along the opposing direction of the side walls 32.

  Both end portions of the base portion 72 enter engagement holes 74 formed in the side walls 32. The engagement hole 74 is formed on the other end side in the longitudinal direction of the side wall 32 with respect to the through hole 60, and the base portion 72 is supported on the side wall 32 so as to be rotatable about its own longitudinal direction around the axis. A pair of substantially fan-shaped lock pieces 76 are formed on both ends in the longitudinal direction of the base 72. The lock piece 76 corresponds to a contact piece 78 extending from both ends in the width direction of the connecting portion 56 (latch 50), and the lock piece 76 is in contact with the contact piece 78.

  Further, a contact portion 80 is formed at the longitudinal intermediate portion of the base portion 72. The contact portion 80 contacts the engagement piece 58 in a state where the engagement piece 58 of the latch 50 is separated from the bottom plate 22.

  On the other hand, the buckle device 1 includes a release button 90 as release means. The release button 90 includes a pressing portion 92 for operation. The pressing portion 92 has a plate shape in which the pressing surface faces the other end in the longitudinal direction of the bottom plate 22, and is a longitudinal direction along the opposing direction of the side walls 32.

  Side walls 94 extend from the vicinity of both ends in the longitudinal direction of the pressing portion 92 toward one end in the longitudinal direction of the bottom plate 22. These side walls 94 are opposed to each other along the opposing direction of the side wall 32 described above, and the end opposite to the bottom plate 22 is connected by the top wall 96, and is opened toward the bottom plate 22 as a whole. It is a concave shape.

  Arms 98 extend from the ends of the side walls 94 opposite to the pressing portions 92 so as to face each other along the opposing direction of the side walls 94. Engaging protrusions 100 are formed at the distal ends of both arms 98 toward the other arm 98, and enter the guide holes 102 formed in the side wall 32. The guide hole 102 is a long long hole along the longitudinal direction of the bottom plate 22. The engagement protrusion 100 can be displaced by a predetermined range along the longitudinal direction of the bottom plate 22 by the inner peripheral portion of the guide hole 102, and thereby the movement direction of the release button 90 is changed in the longitudinal direction of the bottom plate 22 by the guide hole 102. It is regulated.

  A stopper 110 is disposed between the pressing portion 92 and the lock member 70. The stopper 110 includes a plate-like base portion 112 that is formed in a longitudinal direction along the opposing direction of the side wall 94. A pair of concave engaging pieces 114 that are open toward the bottom plate 22 when viewed along the longitudinal direction of the base 112 are formed on both ends of the base 112 in the longitudinal direction. The stopper 110 is supported by the lock member 70 by engaging with the base 72 of the lock member 70 described above.

  Further, an interference portion 116 is formed in the vicinity of both engagement pieces 114 of the stopper 110 so as to be able to interfere with the engagement protrusion 100 of the release button 90 described above.

  A compression coil spring 118 is disposed between the stopper 110 and the pressing portion 92 of the release button 90, and one end of the compression coil spring 118 is in contact with the side opposite to the pressing surface of the pressing portion 92. On the other hand, the other end of the compression coil spring 118 is in contact with the base portion 112 of the stopper 110, thereby urging the stopper 110 in the direction of separating from the pressing portion 92.

  In the buckle device 1, when the insertion plate portion 136 of the tongue plate 130 is inserted from the tongue insertion port 18 of the case 14 in the tongue extraction state shown in FIG. 2, as shown in FIGS. 3 (a) and 4, the insertion plate The tip of the portion 136 abuts against and presses against the end of the ejector 34, and the ejector 34 is opposed to the urging force of the stroke spring 204, overstroke spring 205, and ejector spring 206 in the longitudinal direction of the bottom plate 22. Slide to.

  When the ejector 34 slides by a predetermined amount toward one end in the longitudinal direction of the bottom plate 22, the opposed state between the mounting piece 62 of the ejector 34 and the engaging piece 58 of the latch 50 is released, and the ejector 34 moves the stopper 64 of the latch 50. The latch 50 is rotated by pressing.

  As a result, the tip of the engagement piece 58 moves closer to the bottom plate 22. In this state, the through hole 138 of the insertion plate portion 136 and the through hole 60 formed in the bottom plate 22 overlap. Therefore, in this state, as shown in FIG. 4, the rotated engagement piece 58 passes through the through hole 138 of the insertion plate portion 136 and the through hole 60 of the bottom plate 22.

  Further, when the latch 50 is rotated, the contact state between the engagement piece 58 of the latch 50 and the contact portion 80 of the lock member 70 is released. Here, since the lock piece 76 receives the urging force of the compression coil spring 118 via the stopper 110, the lock member 70 is rotated by the urging force of the compression coil spring 118 so as to be interlocked with the rotation of the latch 50. The piece 76 comes into contact with the contact piece 78 of the latch 50. For this reason, the rotation of the latch 50 in the direction in which the engagement piece 58 is separated from the bottom plate 22 is restricted, and the tongue plate 130 is held in the buckle device 1 to be in the buckle mounted state.

  In this buckle mounted state, as shown in FIG. 3B, the magnet 203 receives a pressing force from the ejector 34 via the overstroke spring 205 and the slide portion 202. As a result, the end of the magnet 203 comes into contact with the contact surface 201c. Further, as shown in FIG. 3C, when the tongue plate 130 is pressed in the insertion direction, the overstroke spring 205 is compressed and the slide portion 202 overstrokes to the right. Does not change in contact with the contact surface 201c.

(Effect of the embodiment of the present invention)
FIG. 6 is a characteristic diagram showing the relationship between the slide amount S of the magnet 203 and the output voltage V. FIG. When the buckle shown in FIG. 3A is not attached, as shown in FIG. 3A, the magnetic field is directed diagonally downward to the left with respect to the MR sensor 210, and the sensor output is the minimum value. On the other hand, when the buckle shown in FIG. 3B is attached, the slide amount of the magnet 203 is L shown in FIG. 6, and the magnetic field is directed obliquely upward to the left with respect to the MR sensor 210. Maximum value. However, even during the overstroke shown in FIG. 3C, the position of the magnet 203 does not change and the slide amount of the magnet 203 remains L, and the output voltage V is the same as when the buckle is attached. Therefore, the output voltage V from when the buckle is not worn to when the buckle is worn varies from the minimum value to the maximum value, and by appropriately setting the threshold value Vth, it is possible to detect the output change easily and accurately. It is possible to discriminate between wearing and non-wearing. Further, since the output voltage V of the MR sensor 210 does not decrease even when the tongue plate 130 is further pushed in, it is not necessary to set the magnet size to a large value, and the state detection device is small and excellent in detection accuracy. A buckle device using the same can be realized. Further, in the buckle mounting and releasing operations until the tongue plate 130 is inserted into the buckle device 1 and the end of the magnet 203 comes into contact with the contact surface 201c, the stroke spring 204, the overstroke spring 205, and the ejector Since each spring constant of the spring 206 is set to K ₁ << K ₂ << K ₃ , the operating force acting on the tongue plate 130 is dominated by the spring constant K _3. A feeling is obtained.

  The embodiment of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, the MR sensor 210 can be arranged at two or more locations. Further, even when the substrate 211 on which the MR sensor 210 is mounted is horizontally arranged, a change in magnetic flux density due to a slide change of the magnet 203 can be detected, and it is possible to determine whether the buckle is attached or not. is there.

DESCRIPTION OF SYMBOLS 1 ... Buckle device, 2 ... Buckle switch, 14 ... Case, 16 ... Anchor insertion port, 18 ... Tongue insertion port, 20 ... Base, 22 ... Bottom plate, 24 ... Anchor plate, 32 ... Side wall, 34 ... Ejector, 34a ... Press Projection part 36 ... guide hole 50 ... latch 52 ... base part 54 ... support hole 56 ... connecting part 58 ... engagement piece 58a ... tip part 60 ... through hole 62 ... mounting piece 64 ... Stopper 70 ... Lock member 72 ... Base part 74 ... Engagement hole 76 ... Lock piece 78 ... Contact piece 80 ... Contact part 90 ... Release button 92 ... Pressing part 94 ... Side wall 96 ... Upper wall, 98 ... arm, 100 ... engagement protrusion, 102 ... guide hole, 110 ... stopper, 112 ... base, 114 ... engagement piece, 116 ... interference part, 118 ... compression coil spring, 130 ... tongue plate, 132 ... Base, 13 ... Slit hole, 136 ... Insertion plate part, 138 ... Through hole, 140 ... Webbing belt, 201 ... Housing, 201a ... Opening part, 201b ... Bottom part, 201c ... Contact surface, 202 ... Slide part, 203 ... Magnet, 204 ... Spring for stroke, 205 ... Spring for overstroke, 206 ... Spring for ejector, 210 ... MR sensor, 211 ... Substrate

Claims (7)

A housing,
A slide portion supported movably by the housing;
A permanent magnet that moves in conjunction with the slide part;
A first elastic member interposed between the slide part and the permanent magnet;
A second elastic member interposed between the permanent magnet and the housing;
A magnetic detector for detecting a change in magnetic flux density from the permanent magnet;
A state detection device comprising:   The state detection apparatus according to claim 1, wherein the rigidity of the first elastic member is larger than the rigidity of the second elastic member.   The state detection device according to claim 1, wherein the housing includes a contact portion that defines a stop position of the permanent magnet that moves in conjunction with the slide portion. A device main body capable of inserting and holding a tongue plate provided on a webbing of a vehicle seat belt device;
The state detection device according to any one of claims 1 to 3, which is placed in the device main body,
A buckle device comprising: A device main body capable of inserting and holding a tongue plate provided on a webbing of a vehicle seat belt device;
A slide part movably supported in the apparatus body;
A permanent magnet that moves in conjunction with the slide part;
A first elastic member interposed between the slide part and the permanent magnet;
A second elastic member interposed between the permanent magnet and the apparatus body;
A third elastic member interposed between the slide portion and the apparatus body;
A magnetic detector for detecting a change in magnetic flux density from the permanent magnet;
A buckle device comprising:   The state detection device according to claim 5, wherein the rigidity of the third elastic member is larger than the rigidity of the first elastic member and the second elastic member. The buckle device according to claim 5, wherein the housing includes a contact portion that defines a stop position of the permanent magnet that moves in conjunction with the slide portion.

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