WO2012146200A1

WO2012146200A1 - Housing for airbag control unit

Info

Publication number: WO2012146200A1
Application number: PCT/CN2012/074887
Authority: WO
Inventors: Ming ZANG; Weijin SONG; Jingyu Pang; Fei DU
Original assignee: Bosch Automotive Products (Suzhou) Co., Ltd.
Priority date: 2011-04-29
Filing date: 2012-04-28
Publication date: 2012-11-01
Also published as: CN202077285U

Abstract

A housing for an airbag control unit includes a housing body (10) which has a bottom wall (5) and a side wall extending upwards from the bottom wall (5), the bottom wall (5) being provided with two mounting portions (7, 8) which are configured for mounting the housing body (10) to a vehicle chassis, wherein the bottom wall (5) is further provided with a locating portion (9) which is offset from a line connecting the two mounting portion (7, 8).

Description

Housing for Airbag Control Unit

Technical Field

The present invention relates to a housing for an airbag control unit. Background Art

Airbag control units are onboard electronic controlling units mounted within vehicles for occupant protection in car crash. The airbag control unit is configured for detecting crash status of a vehicle in real time and sending out a firing instruction whenever it detects a qualified crash to ignite an airbag for protecting occupants.

An airbag control unit is mounted to a vehicle chassis by means of a housing for the airbag control unit, and a signal indicating crash status is delivered to an internal sensor in the airbag control unit through connection between the vehicle chassis and the housing. Because the internal sensor in the airbag control unit is directional, the signal of the sensor can not reflect real crash status of the vehicle if the mounting direction of the sensor is incorrect. Thus, whether the housing is connected to the vehicle chassis correctly or not, and whether the connection is strong enough, are key factors that affect directly precise delivery of the signal which indicates the crash status of the vehicle and to what extent the signal reflects the crash status of the vehicle.

At present, there is a light housing for an airbag control unit in the market, which is mounted to a vehicle chassis in a "two-point locating" manner. The housing for the airbag control unit is provided with two mounting holes thereon, as shown in Figure la, and the vehicle chassis is provided with two corresponding mounting holes. The housing and the vehicle chassis are connected with each other by bolts. The bolts are pretensioned to improve connection reliability and locking capability. The housing is connected to the vehicle chassis by means of pretensioned forces applied on the bolts. Mounting the housing in this way is simply and reduces the mounting time and the mounting cost of the housing.

However, the mounting process of a housing for an airbag control unit is a manual process, and there is a possibility that the housing is mounted incorrectly. For example, because the housing is mounted to a vehicle chassis in a "two-point locating" manner, two mounting portions of housing still provide connecting function even in the case that the real mounting direction of the housing is reversed by 180°. If an operator can not notice the mistake, he would go on to connect bolts.

The situation is disclosed in Figures la and lb. Figures la shows a housing for an airbag control unit is mounted on a vehicle chassis correctly, with an arrow indicating a defined direction of an internal sensor mounted in the airbag control unit. Figure lb shows housing is mounted on the vehicle chassis incorrectly, with the arrow indicating the direction of the internal sensor mounted in the airbag control unit. In the case of being incorrectly mounted, the housing is mounted on the vehicle chassis with the mounting direction being reversed by 180°, which makes the direction of the internal sensor mounted in the airbag control unit incorrect. As a result, a signal received by the airbag control unit is deviated from the real one, which will lead to inadvertent airbag deployment or non-deployment in the worst case. In this case, even if an operator notices the mistake, he have to remove bolts first, correct the mounting direction of the housing, and insert and screw the bolts again, which leads to wastes of time and effort.

In addition, in order to fulfill a "three-point locating" requirement in the market, a vehicle chassis is provided with three holes for mounting a housing for an airbag control unit, which requires to improve the above housing for the airbag control unit to meet this requirement.

Therefore, it is desired to solve the above problems. Summary of the Invention

An object of the invention is to solve the problems mentioned above.

The above problems are solved by the invention through providing a housing for an airbag control unit comprising two mounting portions and a locating portion. The housing can be applied to a vehicle chassis with three mounting holes. The invention also solves the problem that a housing for an airbag control unit with two mounting holes is easy to be mounted incorrectly through providing a locating pin on the housing. For this end, the invention provides a housing for an airbag control unit including a housing body which has a bottom wall and a side wall extending upwards from the bottom wall, the bottom wall being provided with two mounting portions which are configured for mounting the housing body to a vehicle chassis, wherein the bottom wall is further provided with a locating portion which is offset from a line connecting the two mounting portions.

In accordance with a preferred embodiment of the invention, the locating portion extends outwards from the bottom wall.

In accordance with a preferred embodiment of the invention, the housing further comprises a locating pin extending downwards from the bottom wall.

In accordance with a preferred embodiment of the invention, the locating pin comprises a dome shaped tip end and a truncated-cone shaped body.

In accordance with a preferred embodiment of the invention, the locating pin is located on the same side of the line connecting the two mounting portions as the locating portion.

In accordance with a preferred embodiment of the invention, the locating pin and the locating portion are located on opposite sides of the line connecting the two mounting portions respectively.

In accordance with a preferred embodiment of the invention, each of the mounting portions is formed by a metal piece which is at least partially embedded into the bottom wall of the housing body.

In accordance with a preferred embodiment of the invention, the locating portion is formed integrally with the bottom wall of the housing body, or is formed by another metal piece which is at least partially embedded into the housing body.

In accordance with a preferred embodiment of the invention, each of the mounting portions has a mounting hole through which a bolt can pass.

In accordance with a preferred embodiment of the invention, the locating portion is provided with a locating hole, and the locating portion comprises reinforced ribs arranged around the locating hole.

A housing for an airbag control unit according to the invention is provided with two mounting portions and a locating portion, which makes it possible that the housing satisfies requirements of a vehicle chassis with three mounting holes, and a "three-point locating" manner is achieved when the housing is mounted. Therefore, the housing can not be mounted to the vehicle chassis if its position is not correct. The risk that the housing is incorrectly mounted by an operator is avoided.

In this invention, it is particularly advantageous to provide a locating pin when a vehicle chassis is only provided with two mounting holes or when a vehicle chassis is provided with a third whole which has an incorrect position. In the case that the position of the housing is incorrect, the locating pin can not be inserted into a corresponding hole in the vehicle chassis. In this way, the locating pin when cooperating with the mounting holes avoids the risk that the housing is incorrectly mounted by an operator.

Brief Description of the Drawings

The above and other features and advantages of the invention will be better understood with reference to embodiments of the invention in conjunction with the drawings, in which:

Figure la is a view illustrating a light housing for an airbag control unit in the prior art mounted on a vehicle chassis correctly;

Figure lb is a view illustrating the housing in the prior art mounted on the vehicle chassis incorrectly;

Figure 2a shows a front view of a housing for an airbag control unit according to a preferred embodiment of the invention;

Figure 2b shows a top view of the housing according to the preferred embodiment of the invention;

Figure 2c is a view obtained by rotating counterclockwise a bottom view of Figure 2a by 90°. Detailed Description of Preferred Embodiments

A housing for an airbag control unit according to a preferred embodiment of the invention will now be described with reference to the drawings.

A subject matter of the invention is a housing which is configured for accommodating any kind of airbag control unit and for mounting the airbag control unit to a vehicle chassis. The term "vehicle chassis" (not shown) here includes a chassis of any kind of vehicle, or example, a car, a truck, with a mounted airbag control unit.

As shown in Figures 2a-2c, a housing for an airbag control unit according to a preferred embodiment of the invention is preferably formed from a plastic material by molding.

Figure 2a shows a front view of a housing for an airbag control unit according to a preferred embodiment of the invention, and Figure 2b shows a top view of the housing according to the preferred embodiment of the invention,

As shown in Figure 2a, the housing according to this embodiment is shaped like a cup. The housing has an extension 14 extending rightwards (toward the right side of a direction in which a viewer looks at the page surface) from an upper portion of the housing, and the housing further has a housing body 10 comprising a bottom wall 5 and a side wall extending upwards from the bottom wall.

In the illustrated embodiment, the bottom wall 5 is generally rectangular. Alternatively, other shapes can be provided for the bottom wall 5.

The bottom wall 5 of the housing in this preferred embodiment is provided with a first mounting portion 7 and a second mounting portion 8 for mounting the housing body 10 to a vehicle chassis. Each of the first mounting portion 7 and the second mounting portion 8 is formed by a metal piece that is at least partially embedded into the bottom wall 5 of the housing body 10.

The first mounting portion 7 and the second mounting portion 8 are provided with a first mounting hole 1 and a second mounting hole 2 respectively. By means of fasteners passing through the first mounting hole 1 and the second mounting hole 2, the housing body 10 can be mounted to the vehicle chassis. The mounting holes 1 and 2 may be formed by any appropriate technique such as drilling, punching etc. The diameters of the mounting hole 1 and the mounting hole 2 may be determined by calculating based on required connection strength or may be determined based on diameters of fasteners selected in accordance with a user's requirement.

In this embodiment, the housing is connected to the vehicle chassis by means of the fasteners (not shown) passing through the mounting holes 1 and 2. The fasteners may be configured as pretensioned bolts and the mounting holes 1 and 2 may be configured as corresponding threaded holes for the purpose of improving connection rigidity, connection reliability and ability of preventing the bolts from releasing. However, it should be appreciated by those skilled in the art that other types of fasteners can be used for the same purpose.

With reference to Figure 2b, the housing is further provided with a locating portion 9 on the bottom wall 5 so as to avoid the possibility that the housing be mounted incorrectly. This makes it possible that the housing is applied to a vehicle chassis provided with three mounting holes.

In this preferred embodiment, the locating portion 9 is a portion formed integrally with the bottom wall 5 of the housing body 10.

The locating portion 9 is formed with a locating hole 3, as shown in Figure 2b.

In order to mount the housing, an operator have to align the two mounting holes 1 and 2 and the locating hole 3 of the housing body 10 with three corresponding holes of the vehicle chassis to correctly fix the housing. If a mounting mistake shown in Figures lb is made during a mounting process, the locating hole 3 would not be aligned with the corresponding hole of the vehicle chassis, and a part passing through the locating hole 3 can not be inserted into the corresponding hole of the vehicle chassis, which makes the operator realize the mistake, stops the mounting process and correct the position of the housing in time. Therefore, the possibility that the sensors inside the housing receive wrong signals or it takes time and effort to re-mount the housing due to the incorrectly mounting is eliminated. As shown in Figure 2b, the positions of the locating hole 3, the mounting hole 1 and the mounting hole 2 form a triangular, and thus a "three-point locating" manner is achieved. This has an advantage that the housing can not be connected to the vehicle chassis if the housing is rotated from the correct mounting orientation by an angle or is offset from the correct mounting position by a distance, and thus, the possibility of mounting incorrectly is avoided. This structure not only satisfies requirements of the "three-point locating" manner of the vehicle chassis with the three holes, but also prevents the housing from being mounted incorrectly.

It can be seen from above, two pretensioned bolts passing through the first mounting hole and the second mounting hole are sufficient to fix the housing to the vehicle chassis stably enough and securely enough, and the part in the locating hole 3 is only required to cooperate with the two pretensioned bolts to locate the housing. The part in the locating hole 3 can be the same type of fastener as the two pretensioned bolts, or can be a different part, such as an ordinary bolt or a part without thread on its outer surface.

In the preferred embodiment, the locating portion 9 extends outwards on the side away from the extension 14 with reference to a line connecting the first mounting hole 1 and the second mounting hole 2, and has a generally sector-like hollow ear-shaped structure. The locating portion 9 has an edge generally formed by a semicircular segment contiguous with two arc segments, in which the semicircular segment of the locating portion 9 is located away from the side on which the locating portion is connected to the bottom wall 5 of the housing body 10, and the two arc segments symmetrically arranged are configured for connecting the semicircular segment to a corresponding side of the bottom wall 5 of the housing body 10 and are connected to the semicircular segment in a back-to-back manner. The two arc segments are connected to the corresponding side of the bottom wall 5 of the housing body 10 smoothly, which prevents stress from concentrating, as show in Figure 2b.

It should be appreciated by those skilled in the art that while the locating portion 9 is configured as a hollow ear- shaped structure in this embodiment, any other shapes, such as a rectangular, a square, may be adopted for it. In a further embodiment, the locating portion 9 may have a solid ear-shaped structure.

In this preferred embodiment, the locating portion 9 is configured as a "cantilever" extending outwards from the corresponding side of bottom wall 5 of the housing body 10, and the locating portion 9 is further provided with several reinforced ribs 12 and 13 for the purpose of preventing the locating portion 9 from warping during manufacturing, assembly and transportation and for the purpose of improving rigidity of the locating portion 9. Each of the reinforced ribs 13 has one end connected to the bottom wall 5 of the housing body 10 and another end connected to the locating portion 9. By means of the reinforced ribs 12, the semicircular segment of the locating portion 9 is connected to an edge defining the locating hole 3 of the locating portion 9. The reinforced ribs 12 and 13 are generally radially arranged around a periphery of the locating hole 3 for the purpose of preventing stress from concentrating. The reinforced ribs 12 and 13 also have benefits of improving the rigidity and strength of the locating portion 9 and preventing the locating portion from warping during manufacturing, assembly and transportation. Of course, other arrangements of the reinforced ribs are not excluded by the invention.

It is apparent to the skilled in the art that the reinforced ribs 12 and 13 may have an identical cross-sectional shape (shape of a cross-section that is perpendicular to a line connecting two ends of each reinforced rib), or may have different cross-sectional shapes. The number of the reinforced ribs 12 can be the same as or can be different from that of the reinforced ribs 13, and each of the number of the reinforced ribs 12 and that of the reinforced ribs 13 is not limited to that illustrated in this embodiment.

For better description, four sides are identified by 10a, 10b, 10c and lOd in Figure 2b.

In this embodiment, the locating portion 9 is proximate to the side 10b that is opposite to the side to which the extension 14 is proximate with reference to the line connecting the mounting holes 1 and 2, and extends outwards from the left side of the bottom wall 5 of the housing body 10, so that the locating hole 3 is outside of a portion underneath the housing. In other embodiments, the position of the locating hole 3 can be changed. For example, the locating hole 3 may be located proximately to the side lOd that is the same side as the extension 14 with reference to the line connecting the mounting holes 1 and 2.

Alternatively, a distance from the locating hole 3 to the line connecting the mounting holes 1 and 2 may be changed. For example, like the mounting holes 1 and 2, the locating hole 3 may be located right underneath of the housing, and the locating portion 9 may extends inwards from the corresponding side, like the first mounting portion 7 and the second mounting portion 8. For example, the locating portion 9 may have the same shape as the first mounting portion 7 and the second mounting portion 8 or may have a different shape.

In this embodiment, the locating hole 3 may be equidistant from the side 10a and from the side 10c. In other embodiments, a distance from the locating hole 3 to the side 10a or to the side 10c may be changed.

The first mounting portion 7 shown in Figure 2 extends inwards from the side 10c, and the second mounting portion 8 shown in Figure 2 extends inwards from the side 10a. Alternatively, the first mounting portion 7 or the second mounting portion 8 or both of them may be arranged to extend outwards from their corresponding sides, like the locating portion 9. Further, distances from the mounting holes 1 and 2 to the sides 10c and 10a respectively may be changed.

It will suffice for the holes 1, 2 and 3 to form a triangle with their positions, in addition to providing sufficient connection strength. The housing in this embodiment also provides a good appearance. Of course, it should be understood by the skilled in the art that distances between each two of the holes 1, 2 and 3 should be selected appropriately for ensuring stability of the connection between the housing and the vehicle chassis.

Corresponding to the holes 1 , 2, and 3 in the bottom wall 5 of the housing, the vehicle chassis is provided with three corresponding holes which are aligned with the holes 1, 2, and 3 respectively. The first mounting hole 1, the second mounting hole 2 and the locating hole 3 have appropriate spacings between each two of them which form the triangle, which eliminates the possibility of incorrect mounting of the housing.

Moreover, there is a possibility that a housing for an airbag control unit with two mounting holes and a locating hole needs to be mounted to a vehicle chassis with two mounting holes, or the like. In these cases, the risk of incorrect mounting still exists.

This embodiment of the invention solves this problem with a locating pin (a poka-yoke pin) 4 design.

It can be seen from Figure 2a, the housing for the airbag control unit is provided with a locating pin 4 on the bottom wall, the locating pin 4 being a plastic portion formed integrally with the bottom wall 5 of the housing body 10. The locating pin 4 extends downwards from a bottom surface of the bottom wall 5 of the housing body 10 and is tapered along a downward direction from the bottom surface of the bottom wall 5.

The locating pin 4 has one end comprising a planar surface connected to the bottom wall 5 and another end which is formed as a dome. The dome shaped end and the cone shape with a tapered cross-section may perform a guiding function for guiding the locating pin 4 into a corresponding hole formed in the vehicle chassis.

In this preferred embodiment, the locating pin 4 is configured for connecting the housing to the vehicle chassis when cooperating with the mounting portions and the locating portion. The locating pin 4 and the locating hole 3 provide double guarantees which prevent the housing from being incorrectly mounted.

Advantageously, in the case that a vehicle chassis is not provided with a hole corresponding to the locating hole 3 or the hole corresponding to the locating hole 3 is incorrectly located, a "three-point locating" manner is achieved by the locating pin 4 and the first mounting hole 1 and the second mounting hole 2, as the result of which housing can not to be mounted to the vehicle chassis if it has an incorrect position. In other words, that locating pin 4 can still guarantee the housing for the airbag control unit to be mounted to the vehicle chassis correctly, even if the locating hole 3 does not work.

In this preferred embodiment, the diameter and/or the position of the locating pin 4 are illustrated only by an example, and they can be changed as desired.

In this preferred embodiment, the locating pin 4 has a dome shaped end and a truncated-cone shaped body. Alternatively, a cone with a rounded end may be used to replace the dome shaped end for safety. In some cases, a cylindrical locating pin 4 may be used. In addition, the locating pin 4 may be of any other form which can perform locating function.

As shown in Figure 2b, preferably, the locating pin 4 is located proximately to the side lOd which is the same side as the extension 14 with reference to the line connecting the mounting holes 1 and 2. It should be appreciated by the skilled in the art that a distance from the locating pin 4 to the line connecting the mounting holes 1 and 2 can be changed. Further, a distance from the locating pin 4 to the side 10c can vary. In this embodiment, the distance between the locating pin 4 and the side 10c is greater than that between the locating pin 4 and the side 10a.

Moreover, it should be appreciated by the skilled in the art that it is also feasible to locate the locating pin 4 proximately to the side 10b. It is only required that the locating pin 4 does not lie on line connecting the mounting holes 1 and 2. In this embodiment, the locating portion 9 and the locating pin 4 are on opposite sides of the line connecting the mounting holes 1 and 2. In other embodiments, the locating portion 9 and the locating pin 4 can be positioned on the same side with reference to and at different distance from the line connecting the mounting holes 1 and 2.

In this preferred embodiment, the mounting portions 7 and 8 are solid. Each of the mounting portions 7 and 8 has an edge comprising a generally arc segment which is located away from the side where the mounting portion 7 or 8 is connected to the bottom wall 5 of the housing body 10, the generally arc segment being connected to the corresponding side of the bottom wall 5 of the housing body 10 through two linear segments, and there is a proper rounded portion between the generally arc segment and the corresponding side.

While the locating portion 9 in this embodiment is formed as a plastic portion formed integrally with the housing body 10 and does not contribute to the connection strength, the locating portion 9 may be configured as a metal piece, like the illustrated mounting portions 7 and 8, and an part provided in the locating portion 9 may be the same fastener as those in the mounting portions 7 and 8, so that the part provided in the locating portion 9 together with the fasteners in the mounting portions 7 and 8 connect and locate the housing to the vehicle chassis.

The locating portion 9 with the locating hole 3 in this embodiment performs locating function by means of a coupling part passing through the locating hole 3 of the locating portion 9 and through the corresponding hole in the vehicle chassis, however, any other cooperating features which can perform the locating function, for example convex and concave or concave and convex features, can be provided on the locating portion 9 and the vehicle chassis respectively. Likewise, any other cooperating features which can perform locating function, such as convex and concave or concave and convex features, can be provided on the locating pin 4 and the vehicle chassis respectively.

The housing body 10 of the housing of the invention provided with two mounting portions and one locating portion satisfies requirements of the vehicle chassis with three mounting holes, and the "three-point locating" manner is achieved when the housing is mounted. Therefore, the housing can not be mounted to the vehicle chassis in the case of being incorrectly positioned. This avoids the possibility that the housing be mounted incorrectly by an operator.

It is particularly advantageous to provide the locating pin 4 in the case that a vehicle chassis is not provided with a hole corresponding to the locating hole 3 or the hole corresponding to the locating hole 3 is incorrectly positioned. In this case, the locating pin 4 can not be inserted into the corresponding hole in the vehicle chassis if the position of a housing for an airbag control unit is not correct. In this way, the locating pin 4, in cooperation with the mounting holes 1 and 2, avoids the possibility that the housing for the airbag control unit be mounted incorrectly by an operator.

Although some special embodiments have been described above, they are presented only by examples and are not intended to limit the scope of the invention. Rather, the structure described herein can be embodied in many other forms, and various substitutions and changes can be made to the structures and forms described herein without departing from the spirit or scope of the invention.

Claims

1. A housing for an airbag control unit including: a housing body which has a bottom wall and a side wall extending upwards from the bottom wall, the bottom wall being provided with two mounting portions which are configured for mounting the housing body to a vehicle chassis, wherein the bottom wall is further provided with a locating portion which is offset from a line connecting the two mounting portions.

2. The housing for an airbag control unit of claim 1, wherein the locating portion extends outwards from the bottom wall.

3. The housing for an airbag control unit of claim 1 , further comprising a locating pin extending downwards from the bottom wall.

4. The housing for an airbag control unit of claim 3, wherein the locating pin comprises a dome shaped tip end and a truncated-cone shaped body.

5. The housing for an airbag control unit of claim 3, wherein the locating pin is located on the same side of the line connecting the two mounting portions as the locating portion.

6. The housing for an airbag control unit of claim 3, wherein the locating pin and the locating portion are located on opposite sides of the line connecting the two mounting portions respectively.

7. The housing for an airbag control unit of any one of claims 1-6, wherein, each of the mounting portions is formed by a metal piece which is at least partially embedded into the bottom wall of the housing body.

8. The housing for an airbag control unit of claim 7, wherein the locating portion is formed integrally with the bottom wall of the housing body, or is formed by another metal piece which is at least partially embedded into the housing body.

9. The housing for an airbag control unit of claim 7, wherein each of the mounting portions has a mounting hole through which a bolt can pass.

10. The housing for an airbag control unit of claim 8, wherein the locating portion is provided with a locating hole, and the locating portion comprises reinforced ribs arranged around the locating hole.