Patent Description:
The use of snap fit components as a method of assembly are increasing. This increase is due to the reduced cost and reduced manufacturing time required when using snap fit components.

A ratcheting interface could maintain the snap fit over life of the component with increased resistance to being dislodged or pulled off for any reason. The implementations described primarily cover the concept of a ratcheting interface method to assemble an electronic housing.

The present disclosure provides mounting for cover that uses a ratcheting, locking interface. One side may be solid barbs the other side may have a fixed edge and free moving edge to engage barbs in one direction and slip over barbs in other direction. Fixed and movable portions may be switched (e.g. on housing or cover). Further implementations may be used on either the inside or outside walls of housing or cover. According to the present invention, there is provided a mountable sensor assembly as defined by claim <NUM>.

Further objects, features and advantages of this application will become readily apparent to persons skilled in the art after a review of the following description, with reference to the drawings and claims that are appended to and form a part of this specification.

In the accompanying drawings the components are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the application. Moreover, like reference numerals designate corresponding parts throughout the views.

One aspect of the implementations described in this application is the concept of an interlocking ratchet system to fix a cover to an assembly. To allow for the assembly to be water-tight, the design includes a deformable gasket to be used to protect the internals from the outside environment. This gasket would introduce a force that would counter the ratchet system over the life of the assembly.

Another aspect of the described implementations is the use of multiple deforming features to allow increased distribution of stress along the mating features of a ratcheting cover. This increased distribution of stress would increase the robustness of the part and provide a secondary level of safety if the first layer of deformable components were to be broken off.

The implementations described can provide a more robust alternative to the traditional snap fit methods of assembly. Additionally, these implementations can increase the robustness by adding a second layer of resistance to the cover being pulled off, as well as, increased distribution of the stresses that might cause the cover to be compromised.

<FIG> illustrates an exploded view of sensor assembly <NUM>. The sensor assembly <NUM> includes a housing <NUM>, a sensor <NUM>, a gasket <NUM> and a cover <NUM>. The sensor assembly <NUM> may be attached to a sheet metal panel <NUM> of the vehicle. As such, the sensor <NUM> may be an accelerometer, gyroscope, pressure sensor, sound sensor, or other vehicle safety sensor. The housing <NUM> includes a cavity <NUM> to receive the sensor <NUM>. In some implementations, the sensor <NUM> may be attached to a printed circuit board <NUM>. In other implementations, the sensor <NUM> may be mounted directly into the housing <NUM>. The housing <NUM> may also include a connector portion <NUM>. As such, the sensor <NUM> may be electrically connected to pins located within the connector portion <NUM>. The gasket <NUM> may be located between the sensor <NUM> and the cover <NUM>. As the cover is seated on the housing <NUM>, the gasket <NUM> provides sealing between the cover <NUM> and the housing <NUM>, preventing moisture or other elements from travelling into the cavity <NUM>. The cover <NUM> and the housing <NUM> include one or more ratchet assemblies having a first portion <NUM> on the housing <NUM> and second portion (not shown) on the cover <NUM>. In the implementation shown, the ratchet portion <NUM> on the housing <NUM> is located on the outside surface, however, the ratchet portion may be located on the inside surface within the cavity <NUM> in some
implementations. Accordingly, the ratchet portion on the cover could then be within an inside ring or on the outside surface of the cover <NUM>.

<FIG> is a perspective view of the interior of the cover <NUM>. The cover <NUM> has a ratcheting portion <NUM> located on an inside surface of the cover <NUM>. The ratcheting portion <NUM> interfaces with the ratcheting portion <NUM> on the outside surface of the cover <NUM>. As shown in <FIG>, the ratcheting portion <NUM> on the outside surface of the cover <NUM> is fixed, solid ridges (e.g., triangles or barbs). The ratcheting portion <NUM> on the inside surface of the cover <NUM> includes one or more flexible latching fingers <NUM>. The flexible latching fingers <NUM> may have an attachment point <NUM> on an interior surface of and toward the distal end of a peripheral wall <NUM> of the cover <NUM>, and a free end <NUM> that extends from and is not attached to the peripheral wall of the cover <NUM>. However, in some implementations, the free end <NUM> may be loosely or movably attached to the peripheral wall <NUM> of the cover <NUM>. Further, the ratcheting portion <NUM> may include a latching portion <NUM>, such as an edge or ridge, configured to engage the barbs <NUM> or triangles of the ratcheting portion <NUM> on the housing <NUM>. As the ratcheting portion <NUM> is pushed over each barb <NUM> of the ratcheting portion <NUM>, each flexible latching finger <NUM> deflects and then clicks and locks in against each successive barb <NUM> as it passes over the apex of the barb <NUM>. This provides a ratcheting effect where pushing down the cover <NUM> relative to the housing <NUM> will create multiple successive locking latches on each next successive barb <NUM> of the ratcheting portion <NUM>.

<FIG> is a perspective view of the housing <NUM> illustrating the ratcheting portion <NUM> in more detail. The ratcheting portion <NUM> includes multiple barbs, for example four barbs. As shown, the ratcheting portion <NUM> includes barbs <NUM>, <NUM>, <NUM>, and <NUM>. Each barb is located in linear succession. Further, each barb includes a surface <NUM> that protrudes outwardly with a locking edge <NUM> that is configured to catch against the ratcheting portion <NUM> of the cover <NUM>. Each barb is solid and may be non-deformable as illustrated by the triangular cross-section <NUM>.

The ratcheting features (i.e., flexible latching fingers <NUM>) on the cover <NUM> may extend inward while the ratcheting features (e.g. barbs <NUM>) on the housing <NUM> may extend outwardly. Although, the ratcheting features may be switched such that the flexible latching fingers extend outward from the housing <NUM> and the barbs extend inward from the cover <NUM>.

<FIG> is a schematic view of the interaction between the ratcheting portions on the cover <NUM> and the housing <NUM>. The cover <NUM> includes ratcheting portion <NUM> including a plurality of flexible latching fingers <NUM>. The housing <NUM> includes a ratcheting portion <NUM>. The ratcheting portion <NUM> includes a plurality of solid stationary barbs <NUM>. Accordingly, as the cover <NUM> is pressed over the housing <NUM>, the flexible latching fingers <NUM> deflect, as illustrated by arrow <NUM>, as they slide over the apexes of the solid stationary barbs <NUM>. As the flexible latching fingers <NUM> pass the apex of a barb <NUM>, the latching finger springs back as illustrated by arrow <NUM> thereby engaging a retention surface <NUM> of the corresponding barb <NUM>. As the cover <NUM> is pushed onto the housing <NUM> with increasing force, the flexible latching fingers <NUM> are pushed across more barbs <NUM>, causing increasing retention force between the cover <NUM> and the housing <NUM>.

<FIG> illustrates an implementation where stationary barbs <NUM> are located on the inside of the cover <NUM> and the flexible latching fingers <NUM> are located on the housing <NUM>. The cover <NUM> includes ratcheting portion <NUM> including a plurality of stationary barbs <NUM>. The housing <NUM> includes a ratcheting portion <NUM>. The ratcheting portion <NUM> includes a plurality of flexible latching fingers <NUM>. Accordingly, as the cover <NUM> is pressed over the housing <NUM>, the flexible latching fingers <NUM> deflect as they slide over the solid stationary barbs <NUM>. As each flexible latching finger <NUM> passes over the apex of a barb <NUM>, the flexible latching finger <NUM> springs back, thereby engaging the retention surface of the corresponding barb <NUM>. As the cover is pressed onto the housing <NUM> with increasing force, the flexible latching fingers <NUM> are pushed across more barbs <NUM>, causing increasing retention force between the cover <NUM> and the housing <NUM>. The ratcheting features (e.g. flexible latching fingers
<NUM>) on the cover <NUM> extend inward while the ratcheting features (e.g. barbs <NUM>) on the housing <NUM> extend outwardly. Although, the ratcheting features may be switched such that the flexible latching fingers <NUM> extend outward from the housing <NUM> and the barbs <NUM> extend inward from the cover <NUM>.

<FIG> is a schematic view of an implementation where the latching fingers <NUM> are located in a pocket <NUM> of the cover <NUM>. The barbs <NUM> are located on an inside surface <NUM> of the housing <NUM>. The barbs <NUM> will interact and lock with the flexible latching fingers <NUM> as described in the previous implementations. Further, other similar implementations are contemplated herein for example, flexible latching fingers <NUM> may be located on the inside surface <NUM> of the housing <NUM> and the barbs <NUM> may be located in the pocket <NUM> of the cover <NUM>. The ratcheting features (e.g. barbs <NUM>) on the housing <NUM> may extend inward while the ratcheting features (e.g. flexible latching fingers <NUM>) on the cover <NUM> may extend outwardly. Although, the ratcheting features may be switched such that the barbs <NUM> extend outward from the cover <NUM> and the flexible latching fingers <NUM> extend inward from the housing <NUM>.

In addition, other implementations may be contemplated where the peripheral wall <NUM> of the cover <NUM> fits into the cavity <NUM> of the housing <NUM> such that the pocket <NUM> is not used, and ratcheting mechanism <NUM> on the inside surface of the housing <NUM> directly engages the ratcheting mechanism <NUM> on the peripheral wall <NUM> of the cover <NUM>, as shown in <FIG>. As such, the barbs <NUM> or the flexible latching fingers <NUM> may be located on the outer surface <NUM> of the peripheral wall <NUM> of the cover <NUM>, and the corresponding flexible latching fingers <NUM> or barbs <NUM> may be located on the inside surface <NUM>, within the cavity <NUM> of the housing <NUM>.

<FIG> is a schematic view of alternating columns of ratcheting fingers or barbs. The alternating columns may be used to increase the frequency of engagement and increase granularity of compression. Surface <NUM> may include a ratcheting mechanism for example, either the ratcheting fingers or the interacting barbs. The ratcheting fingers and/or barbs may have an alternating pattern of columns to generate an increased frequency of contacts. As shown, the surface <NUM> includes a first set of columns <NUM> of ratcheting fingers or barbs that are offset relative to a second set of columns <NUM> of ratcheting fingers or barbs that provide an increased frequency using spatially offset rows. In some implementations, the rows in the first set of columns may have a higher frequency than the rows in the second set of columns. It can be understood from the diagram a complimentary surface having the opposite of either ratcheting fingers or barbs may interact with the surface <NUM> to lock the cover to the housing with an increased amount of granularity or compression for sealing the sensor assembly.

Claim 1:
A mountable sensor assembly (<NUM>) comprising:
a sensor circuit (<NUM>);
a sensor housing (<NUM>) having walls that define a cavity (<NUM>) with an opening for receiving the sensor circuit (<NUM>);
a cover (<NUM>) configured to enclose the opening; and
a deformable gasket (<NUM>) provided to seal between the cover (<NUM>) and the housing (<NUM>), wherein
the cover (<NUM>) is configured to interface with the walls of the housing (<NUM>) through a ratcheting mechanism that provides a ratcheting effect where pushing down the cover (<NUM>) relative to the housing (<NUM>) creates multiple successive locking latches;
wherein the ratcheting mechanism comprises one or more ratcheting assemblies, where each ratcheting assembly has a first ratcheting portion (<NUM>) on the housing (<NUM>) and a second ratcheting portion (<NUM>) on the cover (<NUM>);
wherein one of the first ratcheting portion (<NUM>) or the second ratcheting portion (<NUM>) comprises a plurality of flexible latching fingers (<NUM>) that engage a plurality of solid ridges (<NUM>) on the other of the first ratcheting portion (<NUM>) or the second ratcheting portion (<NUM>).