JPH10157569A - Acceleration sensor device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable appropriate operation by detecting acceleration acting on a car body even if the position installed on a vehicle is changed. SOLUTION: In this device, a bracket 28 is turnably, pivotally supported on a housing fixed to a car body side. The bracket 28 is turned by a weight 26 provided on the bracket 28 to form a constant position. A sensor ball 30 inertially moved in accordance with acceleration applied to a vehicle and driving an output member is mounted on a ball accepting part formed in the generally crater shape of the bracket 28. An acute angle is assigned to an angle in which the slope surface of a part along an axis crossed at right angles in the horizontal direction with respect to a rotating axial core and at the center of the ball accepting part is made to a horizontal surface rather than an angle is which the slope surface of a site along the rotating axial core of the ball accepting part is made to a horizontal surface. The sensor ball 30 is uniformly rolled even at constant acceleration in any direction to operate an acceleration sensor device for vehicle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle acceleration sensor device used for a retractor for a seat belt device mounted on a vehicle.

[0002]

2. Description of the Related Art Generally, when a large acceleration is applied to a vehicle, a vehicle acceleration sensor for detecting a large acceleration of a predetermined value or more applied to the vehicle to prevent the webbing from being pulled out from the retractor of the seat belt device. Is installed.

[0003] Devices having such a vehicle acceleration sensor device, for example, a seat belt retractor, are mounted on a portion fixed to the vehicle body such as a center pillar or a seat cushion of the vehicle. I have.

However, when this acceleration sensor is mounted on a portion of the reclining seat, such as a seatback retractor, whose angle is changed with respect to the vehicle body, the mounting posture of the acceleration sensor device of this retractor is changed by adjusting the seating posture. Is changed, and an acceleration different from the set acceleration to be detected by the acceleration sensor device is detected.

[0005]

SUMMARY OF THE INVENTION In consideration of the above facts, the present invention takes into account the fact that even if the attitude of the vehicle is changed,
It is an object of the present invention to provide an acceleration sensor device capable of appropriately detecting acceleration acting on a vehicle body.

[0006]

According to a first aspect of the present invention, there is provided a vehicle acceleration sensor device for driving an output member by inertially moving a sensor ball according to acceleration applied to a vehicle. A housing fixed to the vehicle body, a bracket rotatably supported around the axis of rotation of the housing, and the bracket rotating by its own weight even when the mounting angle of the housing to the vehicle body is changed. A weight provided on the bracket so as to rotate around an axis so as to take a fixed posture around the rotation axis of the bracket, and the sensor ball is mounted on the bracket so as to roll freely. The mortar is formed in a substantially mortar shape, and the mortar is formed in a horizontal direction with respect to the axis of rotation, from an angle formed by a slope of the approximately mortar shape along the axis of rotation and a horizontal plane. The angle formed by the substantially mortar-shaped slope along the axis that intersects at right angles at the center of the shape with the horizontal plane is an acute angle, and the sensor ball similarly has a substantially constant acceleration regardless of whether the acceleration acts from any horizontal direction. And a ball receiving portion configured to perform a rolling operation.

With the above-described structure, when acceleration having a component perpendicular to the rotation axis of the bracket is applied to the vehicle acceleration sensor device, the bracket is slightly rotated around the rotation axis. In the moving state, the gentle slope of the portion in the direction perpendicular to the rotation axis of the mortar-shaped slope in the ball receiving portion coincides with the inclination angle of the slope in the direction of the rotation axis of the ball receiving portion with respect to the horizontal plane. Accordingly, the sensor ball can perform a predetermined rolling operation at a constant acceleration.

According to a second aspect of the present invention, there is provided a vehicle acceleration sensor device for driving an output member by inertially moving a sensor ball in accordance with an acceleration applied to a vehicle, wherein the sensor ball is fixed to a vehicle body. Housing, a bracket rotatably supported about the axis of rotation of the housing, and the bracket being rotated about the axis of rotation by its own weight even when the mounting angle of the housing to the vehicle body is changed. A weight provided on the bracket so that the sensor ball takes a fixed posture around the rotation axis of the bracket, and a substantially mortar shape so that the sensor ball can be freely rolled on the bracket. The center of the substantially mortar shape is formed in a horizontal direction with respect to the rotation axis center from an angle formed by the substantially mortar-shaped slope along the rotation axis center and a horizontal plane. The angle formed by the approximately mortar-shaped slope along the axis that intersects at right angles to the horizontal plane is an acute angle, and the sensor ball similarly rolls at a substantially constant acceleration regardless of whether the acceleration acts from any horizontal direction. The ball receiving portion configured as described above, and constitutes at least a part of the output member, is formed in a substantially mortar shape and a concave portion so as to cover the sensor ball, and is formed in the substantially mortar shape concave portion along the rotation axis. The narrow angle of the opposed slopes formed in the substantially mortar-shaped recess along a plane including an axis that intersects at right angles at the center of the substantially mortar-shaped recess from the narrow angle of the formed opposed slopes. A driven concave portion which is formed to have an acute angle so that the substantially mortar-shaped concave portion rolls and interlocks to generate the same moving operation regardless of the direction in which the sensor ball rolls in the ball receiving portion. Pawl with , Characterized by having a.

With the above-described structure, when acceleration having a component in a direction perpendicular to the rotation axis of the bracket is applied to the vehicle acceleration sensor device, the bracket is slightly rotated around the rotation axis. In a moving state, the sensor ball rolls and climbs at a constant acceleration on a gentle slope in a direction perpendicular to the rotation axis of the mortar-shaped slope in the ball receiving portion. The pawl is enlarged by the concave portion, and the pawl performs a predetermined moving operation so that the vehicle acceleration sensor device operates properly.

[0010]

FIG. 1, FIG. 2, FIG. 3, and FIG. 10 show an embodiment in which the vehicle acceleration sensor device of the present invention is configured as an acceleration sensor of a retractor used in a seat belt device. ing.

A lock mechanism 14 and an acceleration sensor main body 16 are mounted on one shaft supporting side surface 12A of a retractor base 12 which supports both ends of a shaft 10 of a spool around which the seat belt webbing W is wound. ing. Further, an upper cover 18 for accommodating the lock mechanism 14 and the acceleration sensor main body 16 is attached to the shaft supporting side surface 12.

As shown in FIGS. 2 and 3, the acceleration sensor main body 16 is
A is attached to a substantially elliptical opening 20 formed in A. As shown in FIG. 1 to FIG.
The weight 26, the bracket 28, the sensor ball 30, the first pawl 32, and the second pawl 34 are mounted in a housing composed of the sensor cover 22 and the hanger 24.

The sensor cover 22 has a cylindrical peripheral wall 38 erected at a right angle from the periphery of a flat plate portion 36 having a shape similar to the opening 20 of the shaft supporting side surface portion 12A and slightly smaller than the periphery thereof. And a flange portion 40 extending outward is integrally provided.

In FIGS. 2, 3 and 5, the portions of the flange portion 40 of the sensor cover 22 which abut rightward in FIGS. 2 and 3 are notched over a small range, and the notches 42 are formed. Each notch 42 is integrally formed with an engaging projection 44 extending from the peripheral wall 38 in a rectangular tongue shape. At the free end of each of the engaging projections 44, there is formed a mooring portion 46 having a slope formed so as to be tapered in a hook shape protruding outward.

The hanger 24 assembled to the sensor cover 22 is integrally formed with a semi-cylindrical peripheral side wall 50 so as to extend in a direction perpendicular to the arc-shaped peripheral end of the front-side semicircular full-surface plate portion 48. By doing so, the inside of the bracket 2
8 are formed. Furthermore, the front plate 4
At the center of each oblique side portion 48B extending in the radial direction and forming an obtuse angle, a small semicircular bearing plate portion 48A protrudes integrally. A small circular shaft hole 52 is formed in the bearing plate portion 48A.

At both ends of the peripheral side wall 50 of the hanger 24, rectangular plate-shaped fixing portions 54 are integrally provided, respectively.
The end opposite to the front plate portion 48 is bent outward at right angles and extends, and each free end has a fixing pin 5.
6 are protrudingly provided. In each fixing portion 54, a shallow groove is formed in a side surface portion facing inward of the peripheral side wall 50 from the front plate portion 48 side to an intermediate portion thereof. The engaging projection 44 is formed in a stepped shape that rises at a right angle from the bottom surface of the base.

The hanger 24 constructed as described above is shown in FIG.
As can be seen from the figure, the free end of the peripheral side wall 50 is brought into contact with the flange portion 40 of the sensor cover 22, and the mooring portion 46 of the engaging projection piece 44 is locked to the locking portion 58, thereby being integrated with the sensor cover 22. Are combined to form a housing of the acceleration sensor main body 16.

A bracket 28 supported inside a housing composed of the sensor cover 22 and the hanger 24.
Is made of a synthetic resin, and is positioned at both ends in the diameter direction of a base 62 having a ball receiving portion 60 which is a substantially distorted mortar-shaped concave portion, toward the side where the ball receiving portion 60 is located (upward in FIG. 3). The extending support plate 64 and the support support plate 66 are provided integrally.
The support plate 64 has a ball receiving portion 60 at the free end of the rectangular small plate.
A small hook-shaped mooring portion 68 bent toward the side is provided integrally,
Further, a small cylindrical shaft pin 70 is integrally provided at the center of the outer side surface of the rectangular small plate opposite to the ball receiving portion 60.

The support support plate 66 has support columns 72 integrally formed on both sides of the rectangular plate, and a bearing hole 74 is coaxially formed at a free end of the support column 72. A small cylindrical shaft pin 76 (FIG. 4) is integrally protruded from the center of the outer surface opposite to the ball receiving portion 60 of the rectangular small plate.

The two shaft pins 70 and 76 have their center lines coaxial, and this center line is
It is arranged so as to be a rotation axis X passing through the center of the sensor ball 30 placed on the zero in a normal state. That is, since these shaft pins 70 and 76 become the rotation axis of the bracket 28, the rotation axis of the bracket 28 is set so as to pass through the center of the sensor ball 30 at the normal position.

The one shaft pin 70 is rotatably supported by the shaft hole 52 of the hanger 24. Also, the other shaft pin 7
6 is supported by a cylindrical bearing portion 78 integrally protruded from the central portion of the flat plate portion 36 of the sensor cover 22. Thereby, the bracket 28 is connected to the sensor cover 22 and the hanger 24.
Are rotatably mounted inside a housing configured in combination with the above.

The ball receiving portion 60 of the bracket 28
Weight engaging portions 80 are integrally provided at both ends in the diameter direction orthogonal to the rotation axis X. In each of the weight engaging portions 80, rectangular base portions 82 are integrally protruded from both side portions of the ball receiving portion 60, and extending directions of the mooring portions 68 and the support columns 72 from a central portion on the outer lower side. In the opposite direction (downward in FIG. 3), a tongue-shaped engaging piece 84 is integrally provided to protrude. Further, at the free end of the attachment piece 84, an engagement protrusion 86 protruding in a hook shape toward the ball receiving portion 60 is integrally formed.

The weight 26 is integrally attached to the bracket 28. The weight 26 is made of metal, and a U-shaped counterweight 90 is provided on one side of a base plate 88 that is assembled such that the bottom surface of the bracket 28 opposite to the ball receiving portion 60 is inserted into the recess. It is formed integrally with the rotation axis X so as to have a target shape. Further, at both corners of the other side surface of the base 88, a small prism-shaped support pillar 92 for mounting the bracket 28 described later is integrally erected. At positions between the respective counterweight portions 90 and the respective support pillar portions 92 of the base plate portion 88, a part of the base plate portion 88 is formed as an engaging groove formed in a rectangular groove shape having a step portion 94 </ b> A. 94 are drilled.

The weight 26 constructed as described above is provided between the pair of counterweight portions 90 by the bracket 28.
Is inserted between the pair of support columns 92, the support column 72 integral with the support support plate 66 is inserted, and the base 82 is inserted between each counterweight 90 and each support column 92. The weight portion 90 is integrally assembled with the bracket 28 by one-touch by inserting the engagement pieces 84 through the engagement grooves 94 and engaging the engagement protrusions 86 with the step portions 94A. Can be

In the counterweight portion 90, stepped portions 96 are formed at intermediate positions between the outer side surfaces of the respective columnar portions, and each of the columnar portions has an outwardly protruding step 96. The weight 26 integrated with the bracket 28 is rotated. When each step 96
Are in contact with the corresponding side portions 48B to limit the rotation range of the bracket 28.

In the ball receiving portion 60 of the bracket 28,
A sensor ball 30, which is a metal sphere having a diameter of about 12.7 mm, is mounted so as to roll on a slope. The second pawl 34 is mounted on the bearing hole 74 of the support portion 72 of the bracket 28. This second pawl 34 has a beam portion 100 integrally extended from a head 98 having a circular dish-down shape, and a shaft pin portion such that the free end portion of the beam portion 100 has a T-shape. 102 are provided.

The second pawl 34 has a driven pin shown in FIG. 4 in which a shaft pin 102, which is the center of rotation, is inserted into a bearing hole 74 and a substantially mortar-shaped recess is formed in the lower surface of the head 98. The sensor concave portion 104 is mounted so as to cover the sensor ball 30.

As shown in FIG. 2 and FIG. 3, the head 98 of the second pawl 34 has a small rectangular protruding stopper 1.
The stopping projection 106 is movably faced to a position between the anchoring portion 68 of the support plate 64 of the bracket 28 and the base portion 62. When the bracket 28 rotates so as to be inclined with respect to the horizontal direction or when acceleration acts, the sensor ball 30 rolls on the distorted mortar-shaped slope of the ball receiving portion 60 and rides on the outer peripheral side,
When the second pawl 34 is moved so as to be separated from the ball receiving portion 60 by rolling contact with the outer peripheral side of the driven concave portion 104 of the head portion 98, the stopping projection 106 is moved to the mooring portion 68.
And the outer peripheral portion of the ball receiving portion 60 and the driven recess 1
The distance from the outer peripheral portion of the sensor ball 30 is limited to be smaller than the diameter of the sensor ball 30 so that the sensor ball 30 does not fall off from between the ball receiving portion 60 and the driven concave portion 104. A small protrusion for operating the first pawl 32 is provided at the center of the upper surface of the head 98 of the second pawl 34, which is rotated upward by a small angle by the sensor ball 30, on the side opposite to the driven concave portion 104. Part 10
5 are integrally protruded.

The first pawl 32 is formed such that one end of the beam-shaped portion 108 arranged in the lateral direction is raised at a right angle so that the entire shape of the first pawl 32 has an L-shape lying horizontally. This first
A cylindrical bearing hole 110 is provided integrally with a part of the beam-like portion 108 of the pawl 32. In addition, a locking claw 112 that protrudes to one side in a trapezoidal plate shape is formed integrally with a free end that rises at a right angle from the beam-shaped portion 108, and the locking claw 112 does not protrude. A small protrusion-shaped movement range restricting portion 114 is protrudingly provided in the vicinity of the side surface portion. In a portion between the bearing hole portion 110 and the locking claw portion 112 in the beam-shaped portion 108, a receiving surface portion 116 protruding in the same direction as the direction in which the locking claw portion 112 protrudes is provided. The receiving surface portion 116 is curved so as to be convex in the extending direction of the locking claw portion 112 so that the small protrusion portion 105 is brought into sliding contact with the receiving surface portion 116. A contact surface portion 118 is provided.

As shown in FIG. 2, FIG. 3, and FIG.
A brake holding portion 120 is provided integrally with the beam-like portion 108 of the pawl 32 on a side opposite to the locking claw portion 112 and on a free end side with respect to the bearing hole portion 110. This braking holding unit 120
Is formed in a substantially circular arc shape on the front, and the locking claw 11
A portion near the side on the extension side (upper side in FIG. 5) of No. 2 is left as a rectangular protruding stopper-shaped stopping protruding portion 122, and the other portion is cut out in a trapezoidal plane and is recessed toward the back side in FIG. A contact surface portion 124 is formed. The first pawl 32 configured as described above is provided in the bearing hole 110 with the flange portion 4 of the sensor cover 22.
A round shaft bar 126 protruding from 0 is passed through and axially mounted. In the flange portion 40, a column 128 is provided upright in parallel with the round shaft 126 near the outside of the free end of the brake holding portion 120 of the first pawl 32 that is mounted on the round shaft 126. . The free end of the support 128 is attached to the support 12
A holding portion 130 formed in a hook shape is formed integrally so as to be bent in a direction perpendicular to the axis 8 and to reach the sliding contact surface portion 124.

The holding portion 130 is pressed to slide on the sliding surface portion 124, and the first pawl 32 is
6 so that it does not fall off.
The hitting of the stop projection 122 limits the range of rotation of the first pawl 32 in a direction away from the second pawl 34 (direction of arrow A). Further, as shown in FIG.
When the pawl 32 rotates in the direction opposite to the arrow A, the operation range restricting portion 114 hits the stopping protrusion 132 protruding from the flange portion 40 and further approaches the second pawl 34. (The direction opposite to arrow A) is restricted so as not to rotate. Therefore, as can be seen from FIG. 5 and FIG.
The pawl 32 is positioned at the position where the pawl 32 is stopped by the stopping protrusion 122 and the holding unit 130, the operation range limiting unit 114 and the stopping protrusion 13.
2 is freely rotatably supported in a range between the position where the holding portion 130 is stopped by the holding portion 130 and the sliding contact surface portion 1 within the range.
The first pawl 32 is prevented from falling out of the round shaft 126 by pressing the sliding contact surface portion 124 without coming off the slide shaft 24.

As shown in FIGS. 1 to 7, the sensor cover 2
The bracket 28 attached to the inside of the housing constituted by the hanger 24 and the hanger 24 is operated by the weight 26 in a normal use state in which the sensor ball 30 is placed in the ball receiving portion 60, and the shaft pins 70, 76 are provided. The center of gravity of the entire part supported by the shaft pins 70 and 76 is located below the rotation axis of the shaft pins 70 and 76 in the vertical direction. Virtual vertical axis VC perpendicular to the horizontal imaginary line of the ball receiver 60
The bracket 28 automatically adjusts around the rotation axis X so as to be held vertically. Further, the counter weight unit 90
Are perpendicular to the rotation axis of the shaft pins 70 and 76, and when a horizontal acceleration is applied, the rotation axis X of the bracket 28 and the weight 26 supported by the shaft pins 70 and 76
The moment of inertia further vertically below is offset by the moment of inertia vertically above the rotation axis X of the counterweight portion 90, so that the turning operation of the bracket 28 is suppressed.

The bracket 28 includes shaft pins 70 and 7.
Although it is freely rotatable around a range of a predetermined angle around 6,
The ball receiving portion 60 and the driven concave portion 104 are configured so that the acceleration sensor device operates at a constant acceleration even when acceleration is applied from any direction in the horizontal direction.

That is, the rotation axis X of the shaft pins 70 and 76
In the direction, as shown in FIG. 4, the angle θ _A of the inclined surface of the ball receiving portion 60 and the angle θ _B of the inclined surface of the driven concave portion 104 are:
For example, when θ _A = 16.5 degrees, θ _B = 30 degrees is set,
Or, when θ _A = 14 degrees, set θ _B = 15 degrees,
Alternatively, when θ _A = 14 degrees, θ _B = 30 degrees is set.

The angle θ _C of the slope of the ball receiving portion 60 in a cross section along the Y axis orthogonal to the rotation axis X and on the horizontal plane including the rotation axis X, and the slope of the driven recess 104 the angle theta _D, <and θ _a, θ _D> θ _C is set such that theta _B.

As described above, the relationship of θ _C <θ _A , that is, the angle θ _C of the slope of the ball receiving portion 60 in the section along the Y axis is changed to the corresponding angle θ in the section along the rotation axis X. _The reason for making the bracket 28 smaller than _A is as follows.
Is the moment of inertia of the counterweight portion 90 under the acceleration, and the rotational axis X of the bracket 28 and the weight 26 is
The reason for this is to correct an error caused by the bracket 28 slightly rotating about the rotation axis X because the moment of inertia further downward cannot be completely canceled. That is, as shown in FIG. 8 and FIG. 9, for example, when acceleration in the direction of arrow B along the Y axis is applied to the acceleration sensor device,
In the state of FIG. 8 the bracket 28 is fixed in the horizontal direction, the sensor ball 30, the slope of the angle theta _E of the ball receiving part 60 to climb in the direction of arrow C, performs an operation of acceleration detection.
In the state of FIG. 9 in which the bracket 28 is rotatably supported about the rotation axis X, the bracket 28 rotates in the direction of arrow D when acceleration in the direction of arrow B is applied. 30, since no longer must climb steeply and since the angle theta _F slope of the ball receiving part 60 in the direction of arrow C, the steep angle of climb slope resistance increases, it is difficult to climb to the top of the slope of the steep angle Therefore, as compared with the state of FIG. 8, even if the acceleration in the direction of the arrow B is received, the operation of acceleration detection becomes difficult to be performed in the state of FIG. 9, and the sensitivity of acceleration detection is deteriorated. Therefore, the ball receiving portion 60
The angle θ _C of the slope in the cross section along the Y axis at
If the bracket 28 is made acute in advance by the angle of rotation about the rotation axis X in response to the acceleration, the sensitivity of the acceleration detection is corrected so as not to change from the state where the ball receiving portion 60 is fixed horizontally. it can.

Further, as shown in FIG.
When the angle θ _C of the slope of the cross section along the Y-axis is made more acute than θ _A , the moving height distance H with respect to the ball receiving portion 60 when the sensor ball 30 climbs the slope becomes smaller. Therefore, the angle θ _D of the slope of the driven concave portion 104 in the cross section along the Y axis is set to an acute angle than θ _B so that the second pawl 34 can operate properly even at this small distance H. The angle of the theta _D is determined relatively from the relationship between the angle of theta _C.

Also, θ_CTo determine the angle of
The first and second pawls 32 and 34 are set at the time of detecting the acceleration.
The distance to move to the home position (paul gap)
The size of the sabor 30, the bracket 28 and the sensor board
30 and the inertia to the first and second pawls 32 and 34
Determined in consideration of the moment and the like. For example, this acceleration
In the degree sensor device, the rotation axis X direction and the Y axis direction
When the acceleration of 0.3G is applied, the acceleration detection
When performing the operation, the Y axis of the ball receiving portion 60 is
Angle θ of slope of section along_CIs cut along the axis of rotation X.
Angle of slope of surface θ _ASmaller than 0.05G
The speed of the sensor ball 30 is equivalent to that of the ball receiving portion 60.
A sharp angle (horizontal direction)
Angle). This is the slope of the ball receiver 60
Is the same angle over the entire circumference, the rotation of the bracket 28
The acceleration in the Y-axis direction must be 0.35G due to motion
For example, when an acceleration of 0.3 G is applied in the X direction of the rotation axis
Since the acceleration detection operation equivalent to
This is for adjusting by 0.05 G.

In the ball receiving portion 60, the slope between the slope of the section θ _C along the Y axis and the slope of the section θ _A along the rotation axis X is the angle of the slope. Are continuously changed and smoothly continued. Further, a concave portion 60A is formed in the center of the ball receiving portion 60, and the sensor ball 30 is stably placed in the concave portion 60A at normal times.

The acceleration sensor body 1 configured as described above
6, as shown in FIGS. 2 and 3, one of the two fixing pins 56 is passed through a through hole 134 near the opening 20 of the shaft supporting side surface portion 12A, and the other fixing pin 56 is opened. 2
It is arranged at a predetermined position by passing through a long groove 136 formed in a part of the zero. The first pawl 32 of the acceleration sensor main body 16 arranged as described above is located adjacent to the lock mechanism 14 as shown in FIG. 1, and when the acceleration sensor main body 16 performs an acceleration detecting operation, the first pawl 32 It turns in the direction of arrow A, and its locking claw 112 is locked to the V gear 138 of the lock mechanism 14 having a generally used configuration, and the V gear 138 is moved in the direction of arrow E (the webbing pull-out rotation direction). The rotation of is stopped.

As shown in FIG. 1, when the webbing W is pulled out by a small amount in a state where the rotation of the V gear 138 in the direction of arrow E is stopped by the first pawl 32, the spool shaft 1
0 rotates in the webbing pull-out rotation direction by a small amount. Then, the spool shaft 10 and the V gear 138 rotate relatively, and a pair of lock pieces 14 attached to the spool shaft 10 side.
0, the pin 146 protruding from the side
8 is moved by being slid in the cam groove 148 of the shaft 8 so that the tooth 142 of the lock piece 140 is moved to the side of the shaft supporting side 1.
It is configured to mesh with a lock internal tooth portion 144 in the form of an internal gear formed in 2A to prevent the rotation of the spool shaft 10 in the webbing W pull-out direction. The lock mechanism 14
Other various configurations may be used.

Next, the operation and operation of the acceleration sensor device according to the present embodiment configured as described above will be described.

As shown in FIGS. 10 and 5, when the inclination angle of the seat back B of the reclining seat S mounted in the vehicle is adjusted, the retractor mounted on the seat back B is changed in accordance with the angle change. The bracket 28 of the R acceleration sensor device tilts about the rotation axis X.

At this time, the portion of the bracket 28 pivotally supported around the rotation axis X is caused by the weight of the weight 26.
The original position when the seat back is not tilted is maintained, and the vertical axis VC is always vertical. That is, the bracket 28 rotates about the rotation axis X to maintain the original position.

When an acceleration in the direction of the axis Y orthogonal to the rotation axis X in the horizontal plane is applied to the rotation axis X, the inertial force acting on the base 88 is changed to the inertial force acting on the counterweight 90 as described above. Acts to cancel each other, and suppresses the rotation of the bracket 28 about the rotation axis X.

At this time, the sensor ball 30 is
0 climbs the slope of the ball receiving portion 60 and moves the second pawl 34 along the driven concave portion 104 as shown in FIG.
In the direction of arrow F. Then, this second pawl 34
Of the receiving surface portion 1
The first pawl 32 integral with the webbing 16 is rotated in the direction of arrow A in FIG. 1 to engage the locking claw 112 of the first pawl 32 with the V gear 138 to lock the locking mechanism 14 and to lock the webbing W. Stop the withdrawal operation.

[0047] In the case where the acceleration of the rotational axis X direction is applied, in this direction, since the bracket 28 is not rotated, the inclined surface of the sensor ball 3 of the same angle theta _A normal posture
0 climbs similarly with the same acceleration acting in a different direction, and locks the webbing W as described above to stop the webbing W withdrawal operation. Further, even when the seat back is tilted within a tilt range set in advance, even when acceleration is applied from all horizontal directions in that state, the acceleration sensor device is operated with these substantially constant predetermined accelerations. I can do it.

Further, the seat back of the reclining seat to which the acceleration sensor device according to the present embodiment having the above-described configuration is mounted has a tilt angle of 12 degrees or more and 27 degrees or less.
For example, when tilted to a predetermined tilt angle in the range of 15 to 20 degrees, the acceleration sensor device operates to lock the lock mechanism 14. That is, when the seat back on which the acceleration sensor device is mounted is tilted, the acceleration sensor main body 16 tilts with the operation. At this time, the bracket 28 is tilted about the rotation axis X, the step 96 of the weight 26 hits the side portion 48B of the hanger 24 to stop the operation of the bracket 28, and the sensor ball 30 moves the ball receiving portion 60 by its own weight. Climb, first and second pauls 32,3
4 is operated to lock the lock mechanism 14 to stop the operation of pulling out the webbing W.

In this acceleration sensor device, when the acceleration exerted by the acceleration sensor device stops acting, there is no inertial movement of the occupant, so that there is no force to pull out the webbing W, and the engagement between the V gear 138 and the locking claw 112 is released. As a result, each member returns to the normal state by its own weight.

[0050]

The vehicle acceleration sensor device according to the present invention has an excellent effect that the acceleration applied to the vehicle body can be detected and the vehicle can be appropriately operated even if the attitude of the vehicle is changed.

[Brief description of the drawings]

FIG. 1 is a side view, partially in section, showing a main part of a webbing take-up device to which a vehicle acceleration sensor device according to an embodiment of the present invention is attached.

FIG. 2 is an exploded perspective view showing a main part of the webbing take-up device to which the vehicle acceleration sensor device, a part of which is shown in FIG. 1, is attached.

FIG. 3 is an exploded perspective view showing an enlarged portion of the vehicle acceleration sensor device of FIG. 2;

4 is a longitudinal sectional view of the vehicle acceleration sensor device according to the embodiment of the present invention, taken along line IV-IV of FIG.

FIG. 5 is a partial sectional front view corresponding to a partially enlarged view of FIG. 1, showing a vehicle acceleration sensor device according to the embodiment of the present invention.

6 is a vertical sectional view of the vehicle acceleration sensor device according to the embodiment of the present invention, corresponding to line VI-VI in FIG. 5;

FIG. 7 is an explanatory vertical sectional view showing a main part of the vehicle acceleration sensor device according to the embodiment of the present invention.

FIG. 8 is an explanatory diagram for explaining a main part of an operation of the vehicle acceleration sensor device according to the embodiment of the present invention.

FIG. 9 is an explanatory diagram for describing a main part of an operation of the vehicle acceleration sensor device according to the embodiment of the present invention.

FIG. 10 is a schematic side view illustrating a vehicle seat equipped with a webbing take-up device provided with a vehicle acceleration sensor device according to an embodiment of the present invention.

[Explanation of symbols]

 14 Lock Mechanism 16 Acceleration Sensor Main Body 22 Sensor Cover (Housing) 24 Hanger (Housing) 26 Weight 28 Bracket 30 Sensor Ball 32 First Paul 34 Second Paul 60 Ball Receiver 70 Shaft Pin 74 Bearing Hole 76 Shaft Pin 78 Bearing 102 Shaft pin part 104 Depressed part for driven 110 Bearing hole part 138 V gear

Claims (2)

[Claims] 1. A vehicle acceleration sensor device for driving an output member by inertially moving a sensor ball according to acceleration applied to a vehicle, comprising: a housing fixed to a vehicle body; and a rotation axis of the housing. A bracket rotatably supported around the bracket, and the bracket is pivoted about the axis of rotation by its own weight even when the mounting angle of the housing to the vehicle body is changed, so that the axis of rotation of the bracket is And a weight provided on the bracket so as to take a constant posture around, and the sensor ball is formed in a substantially mortar shape so as to freely roll the sensor ball on the bracket, and is formed along the rotation axis. The mortar along an axis that intersects at right angles at the center of the mortar shape in a horizontal direction with respect to the axis of rotation, from an angle formed by the inclined surface of the mortar shape with a horizontal plane. A ball receiving portion configured such that the angle formed by the slope of the shape with the horizontal plane is an acute angle, and the sensor ball similarly performs a rolling operation at a substantially constant acceleration regardless of whether the acceleration acts from any horizontal direction. A vehicle acceleration sensor device characterized by the above-mentioned. 2. A vehicle acceleration sensor device for driving an output member by inertia-moving a sensor ball according to acceleration applied to a vehicle, comprising: a housing fixed to a vehicle body; and a rotation axis of the housing. A bracket rotatably supported around the bracket, and the bracket is pivoted about the axis of rotation by its own weight even when the mounting angle of the housing to the vehicle body is changed, so that the axis of rotation of the bracket is And a weight provided on the bracket so as to take a constant posture around, and the sensor ball is formed in a substantially mortar shape so as to freely roll the sensor ball on the bracket, and is formed along the rotation axis. The mortar along an axis that intersects at right angles at the center of the mortar shape in a horizontal direction with respect to the axis of rotation, from an angle formed by the inclined surface of the mortar shape with a horizontal plane. A ball receiving portion configured such that the angle formed by the slope of the shape with the horizontal plane is an acute angle, and the sensor ball similarly performs a rolling operation at a substantially constant acceleration regardless of which direction the acceleration acts from; Constituting at least a portion of the sensor ball, formed in a substantially mortar-shaped, concave portion so as to cover the sensor ball, from the narrow angle of the opposed slope formed in the substantially mortar-shaped concave portion along the axis of rotation. At the center of the substantially mortar-shaped recess, a narrow angle of opposing slopes formed in the substantially mortar-shaped recess along a plane including an axis intersecting at right angles at the center is set to an acute angle, and the sensor ball is disposed inside the ball receiving portion. And a pawl having a driven concave portion configured such that the substantially mortar-shaped concave portion rolls and engages with each other to generate the same moving operation, regardless of the direction in which the roller is rolled. Vehicle Degree sensor device.