JP2003175796A - Seat belt tensile force measuring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a seat belt tensile force measuring device which does not interfere with other components and a seat belt in a car body in terms of position and can measure a component force in the vertical position as it is. <P>SOLUTION: In the steady state, a rivet 3 is energized downward in the Fig. 1 by an elastic force of elastic members 13a and 13b, and an anchor 2 and a bush 4 are pressed in contact with the lower end of a long hole 1b. When the tensile force of the seat belt is applied, the anchor 2 is raised to a position where a component force in the length direction of the long hole 1b in the seat belt tensile force is balanced with this energizing force (with rising of the anchor 2, the energizing force is also increased). The reaction force at that time gives a force to push up a recess part 12a of a sensor arm 12 through the elastic member 13b of a rotating elastic part 13. The force is transmitted to a sensor plate 10 and measured by a strain gauge. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for measuring the tension applied to a seat belt for use in air bag deployment control and the like.

[0002]

2. Description of the Related Art An airbag device is provided to protect an occupant in the event of an accident such as a collision. This airbag is designed to be rapidly deployed in the event of an accident to protect the occupant.However, when an infant is placed on the child seat fixed to the seat, the airbag is controlled so that it cannot be deployed. Is coming. Therefore, it has been attempted to detect whether or not the child seat is fixed to the seat by controlling the tension applied to the seat belt that fixes the child seat to the seat to control the expansion of the airbag.

As a seat belt tension sensor used for such a purpose and other purposes, those disclosed in USP 5,996,421 and USP 3,817,093 are known.

[0004] In all of these, the elastic body is bent and deformed by the tension applied to the seat belt, and the bending amount is transmitted to a sensor provided on the elastic body to measure the tension applied to the seat belt. .

[0005]

The applicant of the present invention has also proposed a seat belt tension measuring device which solves the problems of these conventional seat belt tension sensors based on the invention made by its employees, for example, Japanese Patent Application No. 2001-2001. 1643
A patent application has been filed as No. 86 (hereinafter referred to as "prior invention"). FIG. 9 shows a schematic view of a seat belt tension measuring device shown as an embodiment of the invention in this patent application.

As shown in FIG. 9, the tension sensor lower portion 101 is composed of a base plate 102 and a side wall portion 103, for example, a steel base 104, and a rivet 105 on the base plate 102. The strain sensor 106 fixed to the end and the stopper pin 1 for rotating the seat belt
07 and comprises an arm spring 109 pivotally supported by suspending a pivot pin 108 between the two side wall portions 103.

A hole 104a is formed in the base 104, and a bolt is passed through this hole to fix the base 104 to the vehicle body. At that time, the base 104 is configured to be rotatable around the bolt in accordance with the pulling direction of the seat belt.

When tension is applied to the seat belt, the stopper pin 107 is pulled to the right side of the drawing, which causes the arm spring 109 to rotate around the pivot pin 108. The arm spring 109 is composed of a base end portion 110, a spring portion 111, and an abutting portion 112. When the arm spring 109 rotates, the turning force is generated by the spring portion 1.
It is transmitted to the contact portion 112 via 11, and the contact portion 112 presses the strain sensor 106. Therefore, the strain sensor 106
It is possible to measure the rotational force of the arm spring 109 by the output of, and from this, the tension applied to the seat belt can be calculated.

However, the following problems are expected in the seat belt tension measuring device as shown in FIG. 9 including the above-mentioned conventional technique. That is, as shown in FIG. 9, all of these are made rotatable about the mounting bolt in accordance with the seat belt tension direction. Then, as shown in FIG. 10, the sensor body b and the fixing portion c are largely rotated around the mounting bolt d in accordance with the pulling direction of the seat belt a. Therefore, depending on the pulling direction of the seat belt, there is a possibility that other components of the vehicle body and the seat belt tension measuring device may interfere in position. The force you really want to measure is not the tension on the seat belt itself,
The vertical component force (the direction indicated by the white arrow in FIG. 10) is the force, and the seat belt tension itself is measured by the entire rotation. Therefore, in some cases, in order to obtain the vertical component force, it is necessary to separately provide an angle sensor or the like and obtain it by calculation. There may be a case where a mechanism for protecting a harness that guides a signal from the sensor unit to the control unit (housing in a corrugated tube, suppression of bending radius) is required due to movement of the position of the sensor unit due to rotation. There is such a problem.

The present invention has been made in view of the above circumstances, and it is possible to directly measure the component force in the vertical direction without positional interference with other components of the vehicle body and the seat belt. Moreover, it is an object of the present invention to provide a seat belt tension measuring device that does not require protection of a harness.

[0011]

[Means for Solving the Problems] A first means for solving the above problems is fixed directly or indirectly to a vehicle body,
A device for measuring a tension applied to a seat belt, which has an anchor part that is slidable in one direction against a biasing force of an elastic part with respect to a main body part that is directly or indirectly fixed to a vehicle body. , The seat belt is movably attached to the anchor portion, and the tension applied to the seat belt is measured by detecting the biasing force of the elastic portion when the anchor portion is pulled by the seat belt. A seat belt tension measuring device (claim 1) characterized by having the function of:

In the present means, since the seat belt is attached to the anchor portion so as to be movable in that direction, even if the seat belt mounting position changes, the position change of this portion of the anchor portion is allowed. The seat belt tension measuring unit is not affected thereafter. Then, the tension applied to the seat belt is transmitted to the anchor portion, whereby the anchor portion slides in one direction against the biasing force of the elastic portion (restrained in a direction other than the sliding direction).

Since the seat belt tension is detected by measuring the urging force at the time of sliding, the measured force is only the component force in the direction in which the anchor portion moves, of the tension applied to the seat belt. Becomes Therefore, by adjusting the direction in which the anchor moves to the direction in which the component force of the seat belt is to be measured (usually the vertical direction), the conventional problem can be solved and the desired seat belt tension can be measured. it can.

A second means for solving the above problems is
The first means, wherein the main body portion is provided with an elongated hole, is fitted into a hole provided in the anchor portion, and a pin portion slidably provided along the elongated hole; The rotating shaft is attached to the main body, the rotating elastic part is rotatably fitted to the rotating shaft and has a spring body, and the sensor part is attached to the main body. The part is characterized in that one spring body comes into contact with the pin portion and the other spring body comes into contact with the sensor portion to give an urging force between the two (claim 2). is there.

In the present means, when tension is applied to the seat belt, the anchor portion is pulled, whereby the pin portion fitted in the anchor portion moves along the elongated hole provided in the main body portion. Then, the spring body of the rotation elastic portion, which is in contact with the pin portion, receives the rotation force about the rotation axis, and the rotation elastic portion tries to rotate about the rotation axis. This turning force is transmitted to the sensor unit via the spring body, and the urging force is detected by the sensor unit.

A third means for solving the above-mentioned problems is as follows.
The second means is characterized in that a sliding load reducing mechanism is provided between the anchor portion and the main body portion (claim 3).

As described above, the anchor portion and the main body portion slide through the elongated holes, but at that time, sliding load (friction resistance)
Is large, it may cause an error in seat belt tension measurement,
A sliding noise is generated, which causes discomfort. In this means, by providing a sliding load reducing mechanism such as a resin sliding bearing or a resin slider between them, it is possible to prevent occurrence of measurement error and sliding noise. it can.

A fourth means for solving the above-mentioned problems is as follows.
The second means or the third means, characterized in that a stopper for restricting the movement of the anchor portion is provided in order to prevent an excessive force from being applied to the sensor portion ( Claim 4).

When an excessive force is applied to the seat belt due to sudden braking or the like, the force may be transmitted to the sensor portion and an excessive load may be applied to the sensor portion. One solution to this problem is to increase the strength of the sensor section, but in this case, there is a problem that the detection accuracy of the sensor section deteriorates. In this means, the stopper that restricts the movement of the anchor portion prevents an excessive force from being applied to the sensor portion, so that the load applied to the sensor portion can be designed to be small, and the detection accuracy can be improved accordingly. Can be raised.

The fifth means for solving the above-mentioned problems is as follows.
The fourth means is characterized in that the stopper is an elongated hole provided in the main body portion (claim 5).

In the fourth means, the stopper may have any shape, but the structure is simplified by using the elongated hole itself provided in the main body as the stopper as in the present means. You can That is, in the present means, when a certain force or more acts on the anchor portion, the pin portion comes into contact with the end portion of the long hole, and further movement of the anchor portion is prevented. Therefore, the force applied to the sensor unit does not increase further.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings. 1 to 3 show the first embodiment of the present invention.
2A and 2B are diagrams showing an outline of a seat belt tension measuring device as an embodiment of the present invention, FIG. 1 is an exploded perspective view thereof, FIG. 2 is a plan view showing a cover removed, and FIG. ,
(C) is a central longitudinal sectional view. Further, FIG. 3 is a perspective view showing a main part with a cover removed.

In FIG. 1, a fixing hole 1 is formed in a bracket 1 which is a main body fixed directly or indirectly to a vehicle body.
a and a long hole 1b for attaching the anchor 2 are provided. The rivet 3 is inserted into this slot,
The rivet 3 includes a bush 4, a bearing 5, a spacer 6, a slide plate 7, a bearing 8, an anchor 2,
The bush 9 is fitted in this order, the bush 4 is fitted in the elongated hole 1b of the bracket 1, and the bush 9 is fitted in the round hole provided in the anchor 2.

In this way, after these parts are fitted into the rivet 3, one end (right side in FIG. 1) of the rivet 3 is crushed and the parts are integrated via the rivet 3. At that time, the bearing 5, the bracket 1, the slide plate 7, the bearing 8 and the anchor 2 are fitted into the space formed between the bushes 4, the spacer 6 and the bush 9 and the flange portions thereof. .

Even if one end of the rivet 3 is crushed, the dimension between the collars of the bushes in which these members are housed is always constant (depending on the dimensions of the bushes 4 and 9 and the spacer 6). It is determined). In this way, the pin body can be fitted only by sliding along the long hole 1b of the bracket 1. In this embodiment,
Rivet 3, bush 4, bearing 5, spacer 6,
The bearing 8 and the bush 9 form a pin body.

In FIG. 1, the arrow indicates the direction in which the seat belt tension measuring device is actually installed. The left and right correspond to the front-rear direction of the vehicle body (this direction does not correspond to the "direction in the drawing" used in the following description).
The “direction in the drawing”, “upper end”, and the like mean the direction in the drawing. This also applies to the following figures).

On the other hand, a base plate 11 to which the sensor plate 10 is attached is attached to the bracket 1. The base plate 11 has a rotating shaft 11a and a square hole 11b into which the sensor arm 12 is inserted. Then, the rotation elastic portion 13 is fitted into the rotation shaft 11a so as to be rotatable around the rotation shaft 11a. The rotation elastic portion 13 includes two elastic members 13a and 13b.
The elastic member 13a is in contact with the rivet 3 and the elastic member 13b is in contact with the sensor arm 12, respectively. The sensor arm 12 is attached to the sensor plate 10.

A strain gauge (not shown) is attached to the sensor plate 10 so as to detect the deformation of the sensor plate 10, convert it into an electric signal, and output it to the outside through the connector 10a. Has become. In addition, 14 and 15 are covers. More specifically, the sensor plate 10 is screwed to the base plate 11 through two holes 10b, and the sensor arm 12 is fixed to the hole 10c in the middle. When the sensor arm 10 moves, stress is generated between these three holes, and the stress is measured by the strain gauge.

The anchor 2 is provided with a hole 2a through which the seat belt is inserted, and the seat belt is inserted so that its direction can be changed. When a tension is applied to the seat belt, an upward force is applied to the anchor 2 due to this tension, and among these, the long hole 1b of the bracket 1 is included.
The anchor 2 is pulled in the longitudinal direction of the elongated hole 1b (the upward direction in FIG. 1) by the component force in the longitudinal direction of.

In the steady state, the elastic members 13a and 1a
Since the rivet 3 is urged downward by the elastic force of 3b in FIG. 1, the anchor 2 is also pushed until the bush 4 contacts the lower end of the elongated hole 1b. When the seat belt tension is applied, the anchor 2 rises to a position where the component of the seat belt tension in the longitudinal direction of the elongated hole 1b is balanced with this biasing force (with the rise of the anchor 2,
Increased bias).

The reaction force at that time gives a force for pushing up the concave portion 12a of the sensor arm 12 through the elastic member 13b of the rotation elastic portion 13. The force is transmitted to the sensor plate 10 and measured by the strain gauge.

In this embodiment, the bearing 5
Is made of resin and reduces the sliding resistance with the bracket due to the vertical movement of the rivet 3 and the bush 4 to prevent the deterioration of the tension measurement accuracy due to the frictional resistance and to prevent the unpleasant sound from being generated by the sliding. is doing. Similarly, the bearing 8 and the slide plate 7 are also made of resin and play such a role.

In this example, the bushes 4, 9 are
By providing the rivet 3, the force when the one end of the rivet 3 is crushed is prevented from being applied to the bracket 1 and the anchor 2. In particular, the bush 9 facilitates the rotation of the anchor 2 with respect to the bracket 1 and the seat belt. It is also possible to make the anchor 2 face in the pulling direction. Even in this case, the tension measurement of the present embodiment does not cause the problems described in the related art.

At the upper end position of the long hole 1b of the bracket 1, the bush 4 abuts when the anchor 2 receives a force corresponding to the maximum load of the tension detection system.
Even if a greater force is applied to the anchor 2, it serves as a stopper that prevents the force from being transmitted to the tension detection system. Of course, such a stopper may be provided at another position.
Further, even if either one of the elastic members 13a and 13b of the rotating elastic portion 13 is a rigid body, the same effect can be obtained.

An advantage peculiar to the embodiment shown in FIGS. 1 to 3 is that the size of the seat belt tension measuring device can be shortened in the longitudinal direction of the vehicle.

Next, FIGS. 4 to 6 show an outline of a seat belt tension measuring device according to a second embodiment of the present invention.
FIG. 4 is an exploded perspective view, FIG. 5A is a plan view, and FIG.
Is a front view, FIG. 5C is a sectional view taken along line AA, and FIG. 6 is a perspective view.

Two holes 21a are formed in the bracket 21, and the bracket 21 is directly or indirectly attached to the vehicle body by inserting bolts or the like into the holes. Further, the bracket 21 is provided with a long hole 21b for attaching the anchor 22. Although the rivet 23 is inserted into this long hole, the bush 24, the bearing 25, the spacer 26, the anchor 22,
The bearing 27 and the bush 28 are fitted in this order,
The bush 24 is fitted in the elongated hole 21 b of the bracket 21, and the bush 28 is fitted in the round hole provided in the anchor 22.

After these parts are fitted into the rivet 23 in this way, one end (left side in FIG. 4) of the rivet 23 is crushed, and these parts are integrated via the rivet 23. At this time, the bearing 25, the bracket 21, the bearing 27, and the anchor 22 are fitted into the space formed by the bush 24, the spacer 26, and the bush 28 contacting each other and formed between the flange portions. Even if one end of the rivet 23 is crushed, the dimension between the collars of the bushes in which these members are housed is always constant (determined by the dimensions of the bushes 24, 28 and the spacer 26). ).

In this way, the pin body is attached to the bracket 21.
It is possible to make the fitting just slide along the long hole 21b. In this embodiment, the rivet 2
3, the bush 24, the bearing 25, the spacer 26, the bearing 27, and the bush 28 form a pin body.

On the other hand, the base plate 29 is attached to the screw hole 21d of the sensor base attachment portion 21c of the bracket 21, and the sensor plate 30 is attached to the base plate 29 as in the embodiment shown in FIGS. Also installed. A sensor arm 31 is attached to the sensor plate 30.
A strain gauge (not shown) is attached to the sensor plate 30, detects a deformation of the sensor plate 30, converts it into an electric signal, and connects it to the connector 30a.
It is designed to be output to the outside via.

The base plate 29 has a rotating shaft 29a, and a rotating elastic portion 32 is fitted into the rotating shaft 29a so that it can rotate around the rotating shaft 29a. The rotation elastic portion 32 has two elastic members 32a and 32b,
The elastic member 32a contacts the rivet 23, and the elastic member 32b contacts the recess 31a of the sensor arm 31.

The anchor 22 is provided with a hole 22a through which the seat belt is inserted. When tension is applied to the seat belt, an upward force is applied to the anchor 22 due to this tension, of which the long hole 21b of the bracket 21 is provided. The anchor 22 is pulled in the lengthwise direction of the long hole 21b (upward direction in FIG. 4) by the component force in the lengthwise direction. In the steady state, the elastic force of the elastic members 32a and 32b exerts a downward biasing force on the rivet 23 in FIG. 1, so the anchor 22 is also pushed until the bush 24 contacts the lower end of the elongated hole 21b. ing. When the seat belt tension is applied, the anchor 22 rises to a position where the component of the seat belt tension in the longitudinal direction of the elongated hole 21b is balanced with this biasing force (as the anchor 22 rises, the biasing force also increases. ).

The reaction force at that time gives a force to push down the concave portion 31a of the sensor arm 31 via the elastic member 32b of the rotation elastic portion 32. The force is transmitted to the sensor plate 10 and measured by the strain gauge.

In this embodiment, the bearing 2
Reference numeral 5 is made of resin and reduces the sliding resistance with the bracket due to the vertical movement of the rivet 23 and the bush 24, prevents the deterioration of the tension measurement accuracy due to the frictional resistance, and prevents an uncomfortable sound from being generated by the sliding. To prevent. Similarly, the bearing 27 is also made of resin and plays such a role.

In this example, the bush 24,
By providing 28, the force when the one end of the rivet 23 is crushed is prevented from being applied to the bracket 21 and the anchor 22, but in particular, the bush 28 makes it easier to rotate the anchor 22 with respect to the bracket 1 and The anchor 22 may be oriented in the pulling direction of the belt. Even in this case, the tension measurement of the present embodiment does not cause the problems described in the related art.

Further, at the upper end position of the long hole 21b of the bracket 21, the bush 24 abuts when the anchor 22 receives a force corresponding to the maximum load of the tension detection system. Even if it is applied to the anchor 2, it plays the role of a stopper that prevents it from being transmitted to the tension detection system. Of course, such a stopper may be provided at another position. In addition, the elastic members 32a, 3 of the rotation elastic portion 32,
The same effect can be obtained even if either one of 2b is a rigid body.

The embodiment shown in FIGS. 4 to 6 is slightly higher than that shown in FIGS. 1 to 3, but since the bracket is fixed to the vehicle body at two places, There is an advantage that the fixation of is stable.

FIG. 7 shows an outline of a seat belt tension measuring device according to a third embodiment of the present invention. (A) is a top view and (b) is a BB sectional view. In this embodiment as well, the basic structure is the same as in the first and second embodiments, but the elastic rotating member is formed of a torsion coil spring, and one end of the elastic rotating member is directly connected to the load sensor. The difference is that the tension is measured by applying to.

A mounting bolt 42 is attached to the bracket 41.
A hole 41a for attaching the bracket 41 to the vehicle body is formed, and a long hole 41b is formed. A hole 42a is formed in the anchor 42 and the seat belt 4
3 is inserted. The rivet 44 is inserted through the round hole 42b formed in the anchor 42. A spacer 45 and bushes 46, 47 are attached to the rivet 44, and one end of the rivet 44 is crushed and fixed while being fitted into the bracket 41 and the anchor 42 as shown in (b).

A bush 46 is fitted in the elongated hole 41b of the bracket 41 so that it can slide, and a bush 47 is fitted in the round hole 42b of the anchor 42.
In this embodiment, these bushes are made of resin to improve slidability and prevent unpleasant noise from being generated during sliding. Such a configuration can also be used in the first and second embodiments. A shaft 48 is provided on the bracket 1, and a torsion coil spring 49 is rotatably fitted therein. The first end 49a of the torsion coil spring 49 contacts the rivet 44 and urges the rivet 44 to be pushed downward in the drawing. The second end portion 49b is in contact with the sensing portion of the load sensor 50.

When tension acts on the seat belt 43, the anchor 42 moves upward in the figure along the long hole 41b against the biasing force of the torsion coil spring 49. The reaction force causes the torsion coil spring 49 to rotate clockwise in the figure, so that the end portion 48b of the torsion coil spring causes the load sensor 50 to rotate.
Press. Therefore, the seat belt tension can be measured by measuring the pressing force with the load sensor.

The merit of this embodiment is that the size of the vehicle in the height direction can be reduced, so that the foot is not easily caught.

An example of another embodiment is schematically shown in FIG. In (a), the seat belt 62 is inserted through the anchor 61, and the anchor 61 is connected to the lever 63 so as to be relatively rotatable. Fulcrum 6 of this lever
4 and the load sensor 65 are fixed to the floor 66. The force point of the lever 63 is the connecting portion 67 with the anchor 61,
The other end, which is the point of action, presses the load sensor 65 via the compression spring 68.

When tension is applied to the seat belt 62, the anchor 62 moves upward while being restrained by the lever 63,
As a result, the other end of the lever 63 moves downward, and the force pressing the load sensor 65 increases. Therefore, the seat belt tension can be measured by measuring the pressing force. If necessary, a stopper 69 that limits the movement of the lever 63 may be provided to limit the force applied to the load sensor 65.

In (b), since the compression spring 68 in (a) is changed to the tension spring 70, the arrangement of the equipment is changed, but the basic principle is as shown in (a). It is the same, and since it can be easily understood by those skilled in the art that the seat belt tension can be measured by measuring the tensile force applied to the load sensor 65, the same components as those in (a) are the same. The reference numerals are given and the description thereof is omitted.

[0056]

As described above, according to the present invention,
It is possible to measure the component force in the vertical direction as it is without interfering with other seat belt components and the seat belt.
In addition, it is possible to provide a seat belt tension measuring device in which the harness does not move depending on the pulling direction of the seat belt and it is not necessary to protect the harness.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an outline of a seat belt tension measuring device according to a first embodiment of the present invention.

FIG. 2 is a plan view, a bottom view, and a central cross-sectional view showing the outline of the seat belt tension measuring device according to the first embodiment of the present invention.

FIG. 3 is a perspective view showing an outline of the seat belt tension measuring device according to the first embodiment of the present invention.

FIG. 4 is an exploded perspective view showing the outline of a seat belt tension measuring device according to a second embodiment of the present invention.

FIG. 5 is a plan view, a front view, and a sectional view showing an outline of a seat belt tension measuring device according to a second embodiment of the present invention.

FIG. 6 is a perspective view showing an outline of a seat belt tension measuring device according to a second embodiment of the present invention.

FIG. 7 is a diagram showing an outline of a seat belt tension measuring device according to a third embodiment of the present invention.

FIG. 8 is a schematic diagram showing an example of another embodiment of the present invention.

FIG. 9 is a schematic diagram showing an example of an embodiment of the prior invention.

FIG. 10 is a diagram for explaining a problem of the invention of the prior application.

[Explanation of symbols]

1 ... Bracket, 1a ... Hole, 1b ... Long hole, 2 ... Anchor, 2a ... Hole, 3 ... Rivet, 4 ... Bush, 5 ... Bearing, 6 ... Spacer, 7 ... Slide plate, 8 ... Bearing, 9 ... Bush, 10 ... Sensor plate, 1
0a ... Connector, 10b ... Hole, 10c ... Hole, 11 ... Base plate, 11a ... Rotating shaft, 11b ... Square hole, 12 ... Sensor arm, 13 ... Rotating elastic part, 13a, 13b ... Elastic member, 21 ... Bracket, 21a ... hole, 21b ... long hole, 21c ... sensor base mounting portion, 21d ... screw hole, 22 ... anchor, 22a ... hole, 23 ... rivet, 2
4 ... Bush, 25 ... Bearing, 26 ... Spacer, 2
7 ... Bearing, 28 ... Bushing, 29 ... Base plate, 29a ... Rotating shaft, 30 ... Sensor plate, 30a
... connector, 31 ... sensor arm, 32 ... rotation elastic part, 32a, 32b ... elastic member, 41 ... bracket, 4
1a ... hole, 42 ... mounting bolt, 42a ... hole, 42b
… Round holes, 43… Seat belts, 44… Rivets, 45…
Spacers, 46, 47 ... Bushings, 48 ... Shafts, 49 ... Torsion coil springs, 49a, 49b ... Ends, 50 ... Load sensors, 51 ... Harnesses, 61 ... Anchors, 62 ... Seat belts, 63 ... Lever, 64 ... Support points, 65 ... Load sensor, 66 ... Floor, 67 ... Coupling part, 68 ... Compression spring, 69 ...
Stopper, 70 ... Extension spring

Claims (5)

[Claims] 1. A device for directly or indirectly fixing to a vehicle body to measure a tension applied to a seat belt, wherein an elastic portion is attached to a main body portion directly or indirectly fixed to the vehicle body. It has an anchor part that can slide in one direction against a force, and a seat belt is attached to the anchor part so as to be movable in that direction, and the elastic part when the anchor part is pulled by the seat belt. A seat belt tension measuring device having a function of measuring the tension applied to the seat belt by detecting the urging force of the seat belt. 2. The seat belt tension measuring device according to claim 1, wherein the main body part is provided with an elongated hole, and the elongated hole is fitted in the hole provided in the anchor part. A pin portion slidably provided, a rotation shaft attached to the main body portion, and a rotation shaft fitted to the rotation shaft,
It has a rotation elastic part having a spring body and a sensor part attached to the main body part. In the rotation elastic part, one spring body abuts on the pin part and the other spring body functions as the sensor part. A seatbelt tension measuring device, wherein the seatbelt tension measuring device is configured to abut against each other and to apply an urging force therebetween. 3. The seat belt tension measuring device according to claim 2, wherein a sliding load reducing mechanism is provided between the anchor portion and the main body portion. apparatus. 4. The seat belt tension measuring device according to claim 2 or 3, wherein a stopper that restricts movement of the anchor portion is provided in order to prevent an excessive force from being applied to the sensor portion. A seat belt tension measuring device characterized by being provided. 5. The seat belt tension measuring device according to claim 4, wherein the stopper is an elongated hole provided in the main body.