JP2001224408A - Buckle device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a buckle device with a function to perfectly detect whether a tongue plate has been locked or not. SOLUTION: In the case 12 there is provided a magnetic plate 72 which moves by the pressure from the tongue plate 36. The direction of the magnetic field crossing a MRE censor 118 is changed by the magnetic plate 72 coming in contact with or separating from a magnet 116 and whether a latch 84, has locked the tongue plate 30 or not is detected by the MRE censor 118, detecting the change in the direction of the magnetic field. At the same time a magnetic shield 100 is provided on the inside periphery of the case 12 and an exterior magnetic field outside the case 12 is blocked by the magnetic shield 100, preventing the MRE censor from being affected by the exterior magnetic field.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a buckle device for holding an occupant's body in a restrained state by a webbing belt in a vehicle seat belt device.

[0002]

2. Description of the Related Art A buckle device, which constitutes a part of a seat belt device for restraining the body of an occupant seated on a vehicle seat by a long belt-shaped webbing belt, has a tongue plate provided on a webbing belt in a case. With the latch inserted through the hole formed in the tongue plate in the inserted state, the latch is locked and the webbing belt is mounted.

[0003] In such a buckle device, in order to detect whether or not the latch is engaged with the tongue plate, it is determined whether or not the tongue plate is locked by the latch by using a so-called Hall effect sensor. There is a buckle device to detect.

In this type of buckle device, a Hall sensor is arranged so as to face the latch along the movement direction of the latch, and a magnet (permanent magnet) is arranged on the opposite side of the latch via the Hall sensor. The latch is formed of a magnetic material such as iron. When the latch approaches the Hall sensor and the magnet when the latch engages and locks the tongue plate, the magnetic field of the magnet is attracted to the latch, and the magnetic field lines that had not previously traversed the Hall sensor cross the Hall sensor. become. This changes the strength of the magnetic field across the Hall sensor,
When the Hall sensor detects this change in intensity, it is detected that the latch has engaged and locked the tongue plate.

[0005]

However, a magnetic sensor such as the above-described Hall sensor is affected not only by the magnetic field of the internal magnet but also by the external magnetic field outside the buckle device. That is, in the case of the above configuration, if an external magnetic field having the same strength as the strength when the latch is locked acts on the Hall sensor, it is natural that the latch is locked even though the tongue plate is not locked. Mistakes recognition.

An object of the present invention is to provide a buckle device having a function of reliably detecting whether or not a tongue plate is locked in consideration of the above fact.

[0007]

The buckle device according to claim 1, wherein the tongue plate provided on the webbing belt for restraining the occupant's body is inserted into the inside and the tongue plate reaches a predetermined position inside. A device main body provided with a lock member for locking the device, a magnetic field formed around the device main body, and a movement of at least one of the tongue plate and the lock member inserted into the device main body. A magnet in which the magnetic field changes, a magnetic sensor arranged in the magnetic field in the device main body for detecting the change in the magnetic field, and a magnetic body formed inside the device main body and formed by the magnet Magnetic shielding means for magnetically shielding the magnetic sensor against an external magnetic field different from the magnetic field to be applied,
It has.

According to the buckle device having the above-described structure, the tongue plate is inserted into the device main body and reaches a predetermined position in the device main body. In this state, the locking member locks the tongue plate, so that the tongue plate is provided. The worn webbing belt is put on, and restrains the occupant's body.

Further, a magnet is provided in the apparatus main body, and a magnetic field is formed around the magnet. When one of the tongue plate and the lock member inserted into the apparatus main body moves, the magnet is provided. The magnetic field formed by the magnetic field changes, and the change in the magnetic field is detected by the magnetic sensor. Of the change in the magnetic field corresponding to the state where the tongue plate has reached the predetermined position and the change in the magnetic field corresponding to the state where the lock member has moved until the tongue plate locks, the one that can be detected by the magnetic sensor (that is, any one of the above) (A change corresponding to one of the two) is detected by the magnetic sensor. For example, when a change in the magnetic field is detected by the magnetic sensor, an indicator or the like is turned on to recognize that the tongue plate has reached a predetermined position and is locked by the lock member. it can.

Here, in this buckle device, the magnetic sensor is magnetically shielded by a magnetic shielding means against an external magnetic field different from the magnetic field formed by the magnet. That is, since most of the magnetic field lines of the external magnetic field pass through the magnetic shielding means formed of a magnetic material, the magnetic sensor is not located within the range of the external magnetic field, or the magnetic sensor is in the external magnetic field. However, the magnetic flux density of the external magnetic field is extremely small at the position where the magnetic sensor is disposed, and the influence of the external magnetic field on the magnetic sensor is extremely small.

Therefore, the magnetic sensor basically detects only the magnetic field formed by the magnet, and can reliably detect only the change in the magnetic field of the magnet.

[0012] Speaking of magnetic shielding, academically, a closed space is created by a magnetic material. However, the magnetic shielding of the magnetic shielding means in the buckle device does not necessarily mean that a closed space is formed. What is necessary is just to provide so that the influence of an external magnetic field may not affect a magnetic sensor. Therefore, even if the plate-shaped magnetic plate is only provided on the side of the magnet or the magnetic sensor, the magnetic sensor is not located within the range of the external magnetic field, or the magnetic sensor is not positioned within the external magnetic field. Even if the magnetic plate is located at a position where the magnetic plate has a very small magnetic flux density of the external magnetic field at the portion where the magnetic sensor is provided, the magnetic plate serves as the magnetic shielding means in the present invention.

Further, the change in the magnetic field detected by the magnetic sensor in the buckle device may be any of the strength and direction of the magnetic field.

Further, the magnetic shielding means may be provided at least on the side opposite to the magnetic sensor via the magnet. Among the tongue plate and the locking member, the one that changes the magnetic field of the magnet by moving is used. If the configuration is such that the magnet and the magnetic sensor are covered with the magnetic shielding means except for the distance between the two, the external magnetic field is further shielded by the magnetic shielding means.

The form of the magnetic shielding means is not limited as long as it is made of a magnetic material. Therefore, for example, a plate made of a magnetic material such as one or a plurality of iron plates is placed inside the apparatus main body. Or a substantially box-shaped magnetic body having a portion corresponding to one of the above-described one, the magnet, and the magnetic sensor opened. Further, a thin film-shaped magnetic material may be attached to the inner peripheral portion of a case or the like constituting the apparatus main body, and the thin film-shaped magnetic material may be used as magnetic shielding means. Furthermore, a paint or the like containing a powdery magnetic material such as iron powder is applied to the inner peripheral portion of the case or the like, and the paint or the like may be used as a magnetic shielding means, or the powdery magnetic material may be contained. The above-mentioned case or the like may be formed of the synthetic resin material or the magnetic material itself, and the case or the like constituting the apparatus main body may be used as the magnetic shielding means.

[0016]

FIG. 2 is an exploded perspective view of a buckle device 10 according to an embodiment of the present invention, and FIG. 1 is a sectional view of the buckle device 10 at an appropriate position. ing. As shown in these figures, the buckle device 1
0 has a substantially box-shaped case 12. The case 12 is formed of a synthetic resin material, and has a longitudinal slit hole 1 at one end in the longitudinal direction along the width direction of the case 12.
4 and an opening 16 is formed at the other end.

A magnetic shield 100 is provided inside the case 12 as magnetic shielding means. The magnetic shield 100 is formed of a magnetic material such as iron in the form of a thin film or a sheet. When the case 12 is manufactured, the magnetic shield 100 is formed by insert-molding a sheet-like magnetic material constituting the magnetic shield 100. In the present embodiment,
When forming the case 12, the magnetic shield 100 was formed by insert-molding a thin-film or sheet-like magnetic material, but simply attaching the thin-film or sheet-like magnetic material to the inner peripheral portion of the case 12 was performed. With magnetic shield 100
May be formed. In the present embodiment, the magnetic shield 100 is used as a magnetic shielding means using a thin-film or sheet-like magnetic material. For example, a paint or the like containing a magnetic powder such as iron powder is used as a case. When the magnetic powder such as iron powder is contained in a synthetic resin material for forming the case 12, the magnetic powder may be applied substantially uniformly to the inner peripheral portion of the case 12 and used as a magnetic shielding means. The case 12 itself serves as a magnetic shielding means.

A buckle body 20 is housed inside the case 12. The buckle body 20 includes an anchor plate 26 that is attached by rivets 24 to an attachment piece 22 that extends from a vehicle (not shown). The anchor plate 26 is formed by bending the center of the long plate material in the longitudinal direction, and has two parallel upper plates 2 at a predetermined interval.
8 and a lower plate 30 are configured. Anchor plate 26
An insertion hole 32 is formed at the center of one end (bent portion) of the tongue plate 36.
Is an insertion portion 34 formed between the upper plate 28 and the lower plate 30.
Is inserted into. An insertion hole (not shown) is formed in the tongue plate 36, and the webbing of the seat belt device is inserted into the insertion hole. Also, the mounting piece 22
Are inserted and fixed from the other end of the anchor plate 26.

The ejector 3 is provided in the anchor plate 26.
8 is slidably accommodated in the longitudinal direction of the anchor plate 26 (the direction of arrow A in FIGS. 1 and 2 and the opposite direction). An eject spring 40 is disposed between the ejector 38 and the mounting piece 22, and the ejector 38 is moved toward the insertion hole 32 (arrow A in FIGS. 1 and 2).
(Towards the opposite direction).

A pair of square pieces 42 projecting from the both ends in the width direction of the ejector 38 toward the mounting piece 22 are provided. The ejector 38 is pushed by the tongue plate 36 and the mounting piece 22
Is formed at a predetermined position so as to press a projection (not shown) provided on the button 50 at a position substantially at the center in the longitudinal direction of the square piece 42 when it moves toward. The slide of the ejector 38 is a square piece 42.
The abutment portion 46 formed near the tip of the protrusion abuts on a projection (not shown) projecting from the anchor plate 26 into the insertion portion 34, and is limited to a certain range.

The button 50 is located on the upper plate 2 of the anchor plate 26.
It is attached to the 8 side. The button 50 is formed in a substantially quadrangular frame shape in a plan view, and has an operation unit 52 for pressing operation.
And a pair of parallel outer plates 54 protruding from the vicinity of both ends in the width direction of the operation unit 52, and a pair of parallel inner plates 58 protruding from the width direction inside of the outer plate 54. I have.

The outer plate 54 has a claw piece 62 directed inward. The pawl pieces 62 are engaged between the upper plate 28 and the lower plate 30 of the anchor plate 26 from the outside of the anchor plate 26, so that the button 50 cannot be detached from the anchor plate 26, and Longitudinal direction (Fig. 1
And the direction of the arrow A in FIG. 2 and the direction opposite thereto).

A protrusion 64 is provided on the inner surface of the inner plate 58 so as to protrude therefrom. Further, on the operation unit 52 side of the projection 64, a release surface 66 is formed which is gradually inclined in a direction away from the anchor plate 26 toward the operation unit 52. When the tongue plate 36 is not inserted into the insertion portion 34, the projection 64 is provided with a latch 8 as a locking member described later.
4 and the engagement direction (the direction of arrow B in FIGS. 1 and 2)
To prevent the latch 84 from moving. In addition, the protrusion 64
When the tongue plate 36 is inserted into the insertion portion 34 and the latch 84 is engaged with the engagement hole 88 of the tongue plate 36 (locked state), the latch 84 abuts on the upper surface of the contact piece 86 of the latch 84 to engage. The movement of the latch 84 in the release direction (the direction opposite to the arrow B in FIGS. 1 and 2) is prevented.

When the button 50 is moved in the unlocking direction (the direction of the arrow A in FIGS. 1 and 2) in the locked state, the pressing force is applied to the latch 84 in the unlocking direction (FIG. 1).
(In the direction opposite to arrow B in FIG. 2), and pushes contact piece 86 from the lower surface side. As a result, the latch 84 moves in the disengagement direction.

On the upper plate 28, a holding block 80 that straddles the inner plate 58 is provided upright at a position inside the outer plate 54 of the button 50. The holding block 80 has a pair of parallel holding plates 82, and the latch 8 is located between the holding plates 82.
4 are arranged. The holding plate 82 is an anchor plate 2
6 is prevented from moving in the longitudinal direction (the direction of arrow A in FIGS. 1 and 2 and the opposite direction), and the engagement direction and the disengagement direction (the direction of arrow B in FIGS. 1 and 2 and the opposite direction). Direction).

The latch 84 has a substantially U-shape when viewed from the front, and has a contact piece 86 extending outward from the upper end in the width direction. An engagement piece 90 extends from the center of the latch 84 in the width direction toward the tongue plate 36. When the tongue plate 36 is inserted into the insertion portion 34 to a predetermined position, the engagement pieces 90 pass through the through holes 92 formed in the upper plate 28 of the anchor plate 26,
It engages with the engaging hole 88 of the anchor plate 26 and further penetrates a through hole 94 (see FIG. 1) formed in the lower plate 30.

A pair of leaf spring pieces 96 project from the holding block 80 toward the operation portion 52 of the button 50, and urge the button 50 in the direction opposite to the arrow A in FIGS. ing. Thereby, an appropriate resistance is generated when the operation unit 52 is pressed.

An intermediate plate 76 having an appropriate opening is provided between the outer plates 54 of the button 50, and a leg 68 projects downward from the intermediate plate 76. . The leg 68 penetrates a long hole 70 formed in the upper plate 28 and is located between the upper plate 28 and the lower plate 30. Slot 70
Is elongated along the direction in which the button 50 slides, and when the button 50 slides, the leg 68 moves along the long hole 70, and the leg 68 moves along the long hole 70. This causes the button 50 to slide. Slot 70
Are located on the movement locus of the tongue plate 36 that moves between the upper plate 28 and the lower plate 30, and the upper plate 2
When the tongue plate 36 reaches the predetermined position between the lower plate 8 and the lower plate 30, the tongue plate 36 comes into contact with the leg 68, and when the tongue plate 36 slides further in this state, the leg 68 is attached to the tongue plate 36. It is pressed and moves.

The end face of the leg 68 opposite to the side facing the tongue plate 36 located between the upper plate 28 and the lower plate 30 has a magnetic material made of iron or the like. The plate 72 is adhered and fixed.

Further, one end of a leaf spring-shaped lock spring 98 is attached to the button 50. The other end of the lock spring 98 is in contact with the upper surface of the latch 84, and urges the latch 84 in the engagement direction (the direction of the arrow B in FIGS. 1 and 2).

The buckle device 10 includes a sensing unit 112 that constitutes the lock detection device 110.
The sensing unit 112 has a magnet 116.
The magnet 116 is connected to the upper plate 28 via the leg 68 described above.
The tongue plate 36 located between the upper plate 28 and the lower plate 30 has a polarity along the sliding direction of the tongue plate 36 between the upper plate 28 and the lower plate 30. (More specifically, the north pole of the magnet 116 is located on the leg 68 side, and the south pole is located on the opposite side). An MRE sensor (magnetic resistance sensor) 118 as a magnetic sensor is disposed adjacent to the magnet 116 on the leg 68 side of the magnet 116. MRE
The sensor 118 is a so-called ferromagnetic magnetoresistive element in which a pair of resistors each formed of a ferromagnetic material and having a magnetoresistive effect are connected in series in a state of being orthogonally arranged, and the circuit board 120 is connected to the computer 122. , The computer 122 detects the output voltage from the circuit board 120 of the electric circuit including the MRE sensor 118. Further, the computer 122 is electrically connected to an indicator 124 provided on an instrument panel or the like of the vehicle.
When the voltage of the predetermined output from the circuit board 120 is detected, the indicator 124 is turned on.

In this embodiment, the magnetic sensor has an MR
Although the configuration uses the E sensor 118, for example, a Hall sensor using a Hall element as a magnetic sensor may be used.

Next, the operation and effect of this embodiment will be described.

When the tongue plate 36 is not inserted into the insertion portion 34, the projection 64 of the button 50 contacts the contact piece 86 of the latch 84 from below. 84 does not move in the engagement direction (the direction of arrow B in FIGS. 1 and 2).

When the tongue plate 36 is inserted into the insertion portion 34, the tongue plate 36 engages with the ejector 38, and the tongue plate 36 presses the ejector 38, and slides the ejector 38 against the urging force of the eject spring 40. Further, when the ejector 38 slides to a predetermined position, the ejector 38
8, the leg 68 is pressed and moved.

Since the projection 64 of the button 50 is separated from the contact piece 86 of the latch 84 by the movement of the leg 68, the latch 84 receives the urging force of the lock spring 98 and engages in the engaging direction (FIGS. 1 and 2). (In the direction of the arrow B).
4 engages with the engaging hole 88 of the tongue plate 36 through the through hole 92 of the upper plate 28. The button 50 is pushed by the leaf spring piece 96 and moves in the direction opposite to the arrow A in FIGS.
4 contacts the contact piece 86 of the latch 84 from above, thereby preventing the latch 84 from moving in the disengagement direction (the direction opposite to the arrow B in FIGS. 1 and 2).

Here, when the ejector 38 slid by receiving the pressing force from the tongue plate 36 abuts against the leg 68 and presses the leg 68, the magnetic plate 72 provided on the leg 68 becomes a magnet 116. Approach to. When the magnetic plate 72 approaches the magnet 116, the magnetic field formed by the magnet 116 is attracted to the magnetic plate 116, and the magnetic lines of force constituting the magnetic field, particularly, the magnetic lines of force crossing the MRE sensor 118 change their directions. Sensor 11 that changes according to
8 changes. The computer 122 determines whether the output voltage of the electric circuit including the MRE sensor 118 has changed based on the change in the electric resistance value of the MRE sensor 118.
When the computer 122 determines that the output voltage has changed, the computer 122 detects that the tongue plate 36 has reached the predetermined lock position and the tongue plate 36 is locked, and further turns on the indicator 124. . Thereby, the occupant can recognize that the tongue plate 36 is locked.

Here, the buckle device 10 is a case 12
Since the magnetic shield 100 is provided on the inner peripheral portion of
An external magnetic field outside the case 12 is blocked by a magnetic shield 100 formed of a magnetic material. That is, since the magnetic shield 100 is formed of a magnetic material, most of the magnetic field lines of the external magnetic field pass through the inside of the magnetic shield 100. As a result, most of the magnetic field lines constituting the external magnetic field do not reach the MRE sensor 118, or even reach a very small amount (that is, the MRE sensor 118 is not located in the external magnetic field, or the MRE sensor 118 is Even if it is located in a magnetic field, the magnetic flux density of the external magnetic field at this portion becomes extremely small.) For this reason, the external magnetic field does not affect the MRE sensor 118, or the effect is extremely small.
The electric resistance value of the E sensor 118 is affected only by a change in the magnetic field of the magnet 116 due to the contact and separation of the magnetic plate 72 with the magnet 116. Therefore, as a result, the electric resistance value of the MRE sensor 118 changes only in response to the movement of the tongue plate 36, and the tongue plate 36 is not affected by the external magnetic field despite the fact that the tongue plate 36 has not reached the lock position. The lock detection device 110 does not mistakenly recognize that 36 has reached the lock position.

In the present embodiment, the magnetic shield 100 as the magnetic shielding means is formed on the inner peripheral portion of the case 12, but the magnetic shielding means is formed on the inner peripheral portion of the case 12. It is not necessary that the magnetic shielding means be formed of a magnetic material, provided inside the case 12, and provided at a position where the influence of an external magnetic field on the MRE sensor 118 can be prevented or reduced. It is only necessary that three points are satisfied.

Therefore, as shown in a schematic plan view of FIG. 3, for example, a magnetic plate 132 as a plate-shaped shielding means is disposed on the opposite side of the MRE sensor 118 via the magnet 116. Alternatively, the influence of an external magnetic field on the MRE sensor 118 can be prevented or reduced by a plate-shaped magnetic plate 142 as a magnetic shielding means bent in a U-shape in a plan view shown in a schematic plan view of FIG. The configuration may be as follows.

In the present embodiment, the MRE sensor 118 detects a change in the magnetic field accompanying the contact and separation movement of the magnetic plate 72, and indirectly detects whether the tongue plate 36 has reached the lock position. However, the tongue plate 36 may be formed of a magnetic material such as iron and the magnetic field of the magnet 116 may be changed by the contact and separation movement of the tongue plate 36, and the change of the magnetic field may be detected by the MRE sensor 118. .

Further, the present embodiment is set so that the detecting device 110 recognizes that the latch 84 has locked the tongue plate 36 when the tongue plate 36 has reached the lock position. This is not a configuration for detecting whether or not the plate 36 is locked. However, by forming the latch 84 with a magnetic material such as iron, or by providing a magnetic material with the movement of the latch 84,
Can be detected directly or indirectly by the MRE sensor 118. Such a configuration may be adopted, or such a configuration and the tongue plate 36 described above may be used.
May be configured to directly or indirectly detect the movement of the object.

[0043]

As described above, according to the present invention, the influence of the external magnetic field outside the apparatus main body on the magnetic sensor can be prevented or extremely reduced. Therefore, whether or not the tongue plate is locked can be reliably detected by the magnetic sensor.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of a buckle device according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view showing a configuration of a buckle device according to one embodiment of the present invention.

FIG. 3 is a plan view showing a modification of the magnetic shielding means.

FIG. 4 is a plan view showing another modified example of the magnetic shielding means.

[Explanation of symbols]

 Reference Signs List 10 buckle device 12 case (apparatus main body) 36 tongue plate 72 magnetic plate (magnetic material) 84 latch (lock member) 100 magnetic shield (magnetic shielding means) 118 MRE sensor (magnetic sensor) 132 magnetic plate (magnetic shielding means) 142 magnetism Plate (magnetic shielding means)

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masakata Kobe 3-260 Toyota, Oguchi-machi, Niwa-gun, Aichi Prefecture F-term in Tokai Rika Electric Works, Ltd. (reference) 3B090 BC07 BC22

Claims (1)

[Claims] 1. An apparatus body having a tongue plate provided on a webbing belt for restraining an occupant's body inserted therein, and a lock member for locking the tongue plate which has reached a predetermined internal position, A magnet that is provided in the device main body, forms a magnetic field around the magnet, and changes the magnetic field by movement of at least one of the tongue plate and the lock member inserted into the device main body; A magnetic sensor disposed in the magnetic field and detecting a change in the magnetic field; and an external magnetic field formed from a magnetic material and provided inside the apparatus main body and different from the magnetic field formed by the magnet. A buckle device comprising: magnetic shielding means for magnetically shielding a magnetic sensor.