JPH04126170U - collision sensor - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a collision sensor capable of dissipating the kinetic energy of a flyer at a receiving portion of a retainer and ensuring sufficient contact time between the flyer and a contact. [Structure] A flyer 3 made of magnetic material that is attracted by a magnet 2 and a cylinder 4 that restricts the movement of this flyer 3 in one direction are housed in a body 6 and come into contact with the flyer 3 that moves due to collision. In a collision sensor in which a retainer 21 is fitted into the body 6 and has a receiving part 21a for a flying element 3 that holds a contact 5 consisting of a pair of cantilevered elastic pieces 5a and 5b and moves due to a collision, the receiving part 21a of the retainer 21 is
The tapered portions 21b and 21 narrow the movement path of the flyer 3.
By providing the contact point c, it is possible to ensure a sufficient contact time between the flying element 3 and the contact 5.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention can be used in trigger systems such as airbags, which are car occupant protection devices. It is related to collision sensors that are suitable for collision detection, especially the bias force (attraction) of magnets. It relates to a device that detects a collision with a flying object that moves against a force (force).

0002

[Conventional technology]

Conventionally, this type of collision sensor is shown in FIGS. 6 and 7 (D-D sectional view in FIG. 6). (See Japanese Unexamined Patent Publication No. 57-813).

0003 The detailed structure and operation of the collision sensor will be explained with reference to FIGS. 6 and 7. this collision The sensor 1 includes a magnet 2, a flyer 3 made of magnetic material attracted by the magnet 2, A cylinder 4 that restricts the movement of the flyer 3 in one direction, and a flyer that moves in one direction. A pair of inclined cantilevered elastic pieces 5a, 5b that close only when they come into contact with 3. The contact 5, which is placed facing each other, and the flyer 3, cylinder 4, and contact 5 are A tightly built-in resin body 6 (a resin retainer 8 is inserted through a seal 7) It is a structure consisting of two parts (all of which are integrated together). Note that the seal 9 is connected to the cylinder 4 and the bolt. This is to prevent air from flowing into the back of cylinder 4 from the gap in D6. be. Further, the retainer 8 holds the contact 5 and also holds the terminal end 5c of the retainer 8. It protrudes from Na8. As shown in FIG. 8, this terminal end 5c is The terminal board 10 is connected to a connecting terminal 11 via a lead wire 10a. Toko However, such a collision sensor 1 is not attached to the vehicle body as is, but Impact resistance (the collision sensor itself is not damaged before impact is detected) and environmental resistance ( The point of view is that rust will not occur while the product is left attached to the vehicle body etc. for many years. The entire collision sensor 1 is housed in a container 12 made of iron plate, and the surrounding area is surrounded by sand or resin. It is hardened with a filler 13 such as. Then, when solidifying with the filler 13, the collision sensor 1 magnet 2 is attracted to the side surface of the container 12, and the collision sensor 1 is placed on the convex portion 12a of the container. positioning.

0004 Next, the operation of the collision sensor having such a structure will be explained below. The arrow in Figure 6 When an impact occurs in the direction, the flyer 3 overcomes the bias force (attractive force) of the magnet 2. The cantilevered elastic pieces 5a and 5b move forward inside the cylinder 4 and constitute the contact 5. come into contact with. A voltage is applied to the cantilevered elastic pieces 5a and 5b by a battery 14 or the like. When the contact between the flyer 3 and the contact 5 causes a current to flow, electric lightning strikes the airbag device. It is designed to start the pipe 15 etc. The degree of collision detected is determined by the magnet Magnetic strength of 2, gap between flyer 3 and cylinder 4, distance between flyer 3 and contact 5 It is determined by

[0005]

[Problem that the idea aims to solve]

In the collision sensor described in the conventional technology, when a car is decelerated due to a collision, the serial The flyer 3, which moved at high speed along the carrier 4, collided with the receiving part 8a of the retainer 8. It receives a drag force in the opposite direction and is bounced back to the cylinder 4 side at high speed. For this reason, flying The contact time between the child 3 and the cantilevered elastic pieces 5a and 5b forming the contact 5 is extremely short. and can obtain the electrical energy necessary to activate the airbag device. There are cases where it is not possible. Therefore, as shown in FIG. A plurality of protrusions 32 are provided at right angles to the traveling direction of the flying child 3, and the flying child 3 is mounted on these projections 32. The kinetic energy of the flyer 3 in the traveling direction is reduced by making contact with the flyer 3, and the flyer 3 contacts the By reducing the speed of the flying child 3 from when it comes into contact with the object 33 until it leaves the flying child 33, the flying child It is also possible to lengthen the contact time between the contact 33 and the contact 33. However, this passage 31 A collision sensor that secures the contact time between the flyer 3 and the contact 33 using the protrusion 32 inside. In this case, the movement of Flying Child 3 in directions other than the direction of movement becomes large, and Flying Child 3 and contact 33 The contact condition deteriorates, making it impossible to flow the specified current. In addition, the protrusion 32 The position L in the traveling direction and the protrusion height H of the protrusion 32 from the passage 31 surface are manufactured with high precision. If this cannot be met, the sensitivity of the collision sensor itself will be reduced. The problem is that the variation in the sensor becomes large and the sensor no longer functions as a collision sensor in the event of a collision. It has points.

[0006] The present invention was made in view of these problems of the conventional technology. The purpose of this is to ensure sufficient contact time between the flyer and the contact during a collision. The present invention is intended to provide a collision sensor that can be obtained in real time.

[0007]

[Means to solve the problem]

In order to solve the above object, the collision sensor of the present invention is attracted by a magnet. The body consists of a flyer made of magnetic material and a cylinder that restricts the flyer's movement in one direction. It consists of a pair of cantilevered elastic pieces that are housed inside and come into contact with the flying object that moves due to collision. A retainer that holds the contact and has a receiving part for the flying element that moves due to collision is attached to the bolt. In the collision sensor fitted into the cage, the flying element's movement path is provided in the receiving part of the retainer. A tapered part is provided to narrow the area.

[0008]

[Effect]

The flying element causes elastic and plastic deformation over a long section on the receiving part of the retainer, Furthermore, since the retainer receives frictional force from the receiving part, most of the kinetic energy is heat, Dissipated energy increases as it changes to something other than mechanical energy such as sound. The restoring energy is extremely reduced, and the flyer is pulled back toward the cylinder at a low speed. Ru. In addition, in some cases, the flying element may be caught between the tapered part of the retainer's receiving part. .

[0009]

【Example】

Embodiments of the present invention will be described below with reference to the drawings. Figure 1 shows the collision sensor of the present invention. 2 is a sectional view taken along the line AA in FIG. 1, and FIG. 3 is a sectional view taken along the line BB in FIG. Na Also, parts having the same functions as those in FIGS. 6 to 8 are given the same reference numerals and their explanations are Omitted. The difference from FIGS. 6 to 8 is that the flying element movement path is narrowed in the receiving part of the retainer. The point is that a tapered portion is provided to reduce the impact.

0010 In FIGS. 1 and 2, the movement of the flyer 3 from the cylinder 4 in the collision sensor 20 To narrow the passage, the receiving part 21a of the resin retainer 21 is made at an angle α with the axial direction. None, the axial length is h, and the tapered part 2 is symmetrical with respect to the center of the retainer 21. 1b and 21c are provided at right angles to the cantilevered elastic pieces 5a and 5b constituting the contact 5. There is. This angle α is 45° or less, and the length h is the length h of the The length is such that the flying child 3 does not come into contact with the bottom surface 21d of the receiving part 21a when the child 3 is inserted. be. This retainer 21 is integrated into the resin body 6 by caulking via a seal 7. has been done. Further, the retainer 21 holds the contact 5 and the terminal end 5c thereof. protrudes from the retainer 21.

[0011] Next, the operation of this collision sensor 20 will be explained with reference to FIG. Normal time, Shoko 3 is a rear end surface 6a of the body 6 due to the bias force of the magnet 2, as shown in FIG. It is held in close contact with the When the vehicle body decelerates due to a collision, etc. The deceleration is transmitted to the body 6 of the collision sensor 20. On the other hand, progress is being made to Hisoko 3. A directional inertial force is acting. As a result, when the deceleration is larger than the predetermined value, , the flyer 3 overcomes the bias force of the magnet 2 and moves forward inside the cylinder 4 in the direction of arrow A. As shown in FIG. 3(b), the cantilevered elastic pieces 5a and 5b forming the contact 5 are Contact.

0012 A voltage is applied to the cantilevered elastic pieces 5a and 5b by a battery 14 or the like, and the flying element 3 contacts the cantilevered elastic pieces 5a and 5b, the electric detonator 15 of the airbag device, etc. Current flows to start it up. The flying child 3 in contact with the cantilevered elastic pieces 5a and 5b It overcomes the bias force of the magnet 2 and moves further inside the cylinder 4, and the retainer 21 It reaches the receiving part 21a. In the receiving part 21a of the retainer 21, as shown in FIG. 3(c), The flying element 3 collides with the tapered portions 21b and 21c, but does not contact the bottom surface 21d. this During this period, the cantilevered elastic pieces 5a and 5b are deformed by the flying element 3, but the cantilevered elastic pieces 5a and 5b are The contact state between the elastic pieces 5a and 5b is maintained, and the current continues to flow.

[0013] The tapered portions 21b and 21c narrow the path of movement of the flyer 3 from the cylinder 4. Since the flyer 3 is provided symmetrically with respect to the center of the retainer 21, the flyer 3 It collides with the pad portions 21b and 21c at the same time. The tapered portions 21b and 21c are aligned in the axial direction. Since the angle α is less than 45° and the velocity of the flyer 3 after the collision is in the direction of travel, , Shoko 3 does not bounce back and tries to advance further. Meanwhile, Shoko 3 causes elastic and plastic deformation over a long section on the tapered parts 21b and 21c, Further, it receives frictional force from the tapered portions 21b and 21c. In the end, Shoko 3 has Most of the kinetic energy is converted into something other than mechanical energy such as heat and sound, and is restored. Energy decreases drastically.

[0014] Flyer 3 uses the slight remaining restoring energy, the bias force of magnet 2, and cantilever elasticity. It is pulled back toward the cylinder 4 by the resultant force of the restoring forces of the pieces 5a and 5b. This flying child 3 The pulling back to the cylinder 4 side requires extremely little restoring energy, so it is done at low speed. It will be done. Then, the flying child 3 changes from the position shown in FIG. 3(c) to the position shown in FIG. 3(b). While the cantilevered elastic pieces 5a and 5b are pulled back, the elasticity of the cantilevered elastic pieces 5a and 5b The contact state between 5b and the flying element 3 is maintained, and the current continues to flow. Therefore, Shoko 3 Sufficient time is secured from when the cantilevered elastic pieces 5a and 5b come into contact until they separate, and the Ensure that the electrical energy necessary to activate the electric detonator 15 of the abag device is obtained. can be done. In addition, if the deceleration that occurs in the vehicle body due to a collision is large, After the flying child 3 collides with both tapered parts 21b and 21c of the receiving part 21a of the retainer 21. The speed of the flyer 3 also increases, but since the retainer 21 is made of resin, the flyer 3 The tapered portions 21b, 21 advance as if biting into the tapered portions 21b, 21c. It is stuck in c and stands still. Therefore, the flying element 3 and the cantilevered elastic pieces 5a and 5b are in contact with each other. In this case, the flying child 3 comes to rest on the receiving part 21a of the retainer 21 in the state of contact. It also ensures the electrical energy necessary to activate the electric detonator 15 of the airbag device. can be obtained.

[0015] In addition, in the above embodiment, a pair of cantilevered elastic pieces constituting the contact are attached to the retainer. Although we have explained what is held at the bottom, Figures 4 and 5 (C-C sectional view of Figure 4) As shown in the figure, this pair of elastic pieces is attached to a collision sensor that extends sideways from the inner surface of the retainer. can also be applied. In this collision sensor, the retainer 23 is composed of a lid body 24 and a block 25. The movement of the flying element 3 from the cylinder 26 is arranged in the receiving part 24a of the lid body 24. Tapered portions 24b and 24c are provided to narrow the passage. And bro A pair of cantilevered elastic pieces 27a and 27b of the contact 27 are installed on the inner surface of the hook 25. and its end is drawn out sideways. In this case as well, the kinetic energy of Toshiko 3 is dissipated and the restoring energy becomes small, so the flying element 3 moves to the cylinder 26 side at a low speed. , and the same effect as in the above embodiment is achieved.

[0016]

[Effect of the idea]

Since the present invention is configured as described above, it produces the effects described below.

[0017] When deceleration occurs in the vehicle body due to a collision, etc., the flyer is installed in the receiving part of the retainer. The flying object collides with the tapered part that narrows the moving path, and the kinetic energy is dissipated and the projectile recovers. Original energy becomes smaller. For this reason, Shoko uses the slight remaining restoring energy and magnetic The resultant force of the bias force of the stone and the restoring force of the cantilevered elastic piece pulls it toward the cylinder at a low speed. Sufficient time is ensured between when the flying child contacts the cantilevered elastic piece and when it leaves the cantilevered elastic piece. The electrical energy required to activate the electric detonator, etc. of the airbag device. can be obtained with certainty. In some cases, the flying element may be in contact with a cantilevered elastic piece. When touched, it is caught in the tapered part of the receiving part of the retainer and comes to rest. Therefore, this In the case of You can definitely get it.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a collision sensor of the present invention.

FIG. 2 is a sectional view taken along line AA in FIG. 1;

FIG. 3 is a sectional view taken along line BB in FIG. 1;

FIG. 4 is a cross-sectional view of another collision sensor.

FIG. 5 is a sectional view taken along line CC in FIG. 4;

FIG. 6 is a cross-sectional view of a conventional collision sensor.

FIG. 7 is a sectional view taken along line DD in FIG. 6;

FIG. 8 is a diagram showing a state in which the collision sensor is housed in the container.

FIG. 9 is a sectional view of a conventional collision sensor.

[Explanation of symbols]

2 magnet 3 Hiyoko 4 cylinder 5 Contact 6 Body 21 Retainer 21a Receiving part 21b, 21c taper part

──────────────────────────────────────────────── ─── Continuation of front page (72) Creator Atsushi Taniguchi 1764-1 Mukohara, Kami Inayoshi, Chiyoda Village, Niiharu District, Ibaraki Prefecture Sensor Technology Co., Ltd. Tsukubaji Inside the office (72) Creator Masaharu Kakitani 1764-1 Mukohara, Kami Inayoshi, Chiyoda Village, Niiharu District, Ibaraki Prefecture Sensor Technology Co., Ltd. Tsukubaji Inside the office (72) Creator Etsujiro Imanishi 1764-1 Mukohara, Kami Inayoshi, Chiyoda Village, Niiharu District, Ibaraki Prefecture Sensor Technology Co., Ltd. Tsukubaji Inside the office

Claims (1)

[Scope of utility model registration request] Claim 1: A flyer made of magnetic material that is attracted by a magnet and a cylinder that restricts the movement of the flyer in one direction are housed in a body, and a pair of cantilevers are in contact with the flyer that moves due to collision. In a collision sensor in which a retainer is fitted into the body, the retainer holds a contact made of an elastic piece and has a receiving part for a flying element that moves due to a collision, and a tapered part is provided in the receiving part of the retainer to narrow a movement path of the flying element. A collision sensor characterized by: