Ratchet cover for sensor housing

Description

BACKGROUND

[0001] The present application relates generally to a ratcheting cover for a sensor housing.

[0002] 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. US4850228 discloses a snap fit component to join an outer cover to a base. The outer cover has hook members disposed on opposite sides thereof and having ridges projecting outwardly. When the ridges fittingly engage the wedges, respectively, on the base, the hook members firmly join the outer cover and the base to each other. A problem with this method of assembly, however, is that it increases the possibility of contaminants reaching electronics that may be sealed in the components. This may be increasingly important with safety sensors. US8051707B2 discloses a sensor arrangement including an optical sensor, a non-optical sensor, a sensor holder, and main and flexible interconnect devices. US8359929B2 discloses an arrangement for a surface mounted instrument that may be installed to seal against a mounting surface in spite of possible imprecise installation of a standard rough-in box or irregularities in the mounting surface. CN105043349A discloses a mounting arrangement for an inclination sensor intended for use in regulating the position of the optical axis of a vehicle headlight. JP2007155505A discloses a mounting arrangement for a pressure sensor. The implementations described aim to provide an alternative solution to classic snap fit designs and solve associated problems. BRIEF SUMMARY

[0003] 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.

[0004] 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 1.

[0005] 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.BRIEF DESCRIPTION OF THE DRAWINGS

[0006] 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. FIG. 1 is an exploded view of a sensor assembly. FIG. 2 is a perspective view of the interior of the cover for the sensor assembly. FIG. 3. Is a perspective view of the housing illustrating one implementation of the ratcheting portion. FIG. 4 is a schematic view of the interaction between the ratcheting portions on the cover and the housing. FIG. 5 is a schematic view of another implementation of the interaction between the ratcheting portions on the cover and the housing. FIG. 6 is a schematic view of another implementation of the interaction between the ratcheting portions on the cover and the housing. FIG. 7 is a schematic view of another implementation of the interaction between the ratcheting portions on the cover and the housing. FIG. 8 is a schematic view alternating rows of ratcheting fingers or barbs. DETAILED DESCRIPTION

[0007] 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.

[0008] 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.

[0009] 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.

[0010] FIG. 1 illustrates an exploded view of sensor assembly 100. The sensor assembly 100 includes a housing 110, a sensor 120, a gasket 124 and a cover 126. The sensor assembly 100 may be attached to a sheet metal panel 130 of the vehicle. As such, the sensor 120 may be an accelerometer, gyroscope, pressure sensor, sound sensor, or other vehicle safety sensor. The housing 110 includes a cavity 112 to receive the sensor 120. In some implementations, the sensor 120 may be attached to a printed circuit board 122. In other implementations, the sensor 120 may be mounted directly into the housing 110. The housing 110 may also include a connector portion 114. As such, the sensor 110 may be electrically connected to pins located within the connector portion 114. The gasket 124 may be located between the sensor 120 and the cover 126. As the cover is seated on the housing 110, the gasket 124 provides sealing between the cover 126 and the housing 110, preventing moisture or other elements from travelling into the cavity 112. The cover 126 and the housing 110 include one or more ratchet assemblies having a first portion 140 on the housing 110 and second portion (not shown) on the cover 126. In the implementation shown, the ratchet portion 140 on the housing 110 is located on the outside surface, however, the ratchet portion may be located on the inside surface within the cavity 112 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 126.

[0011] FIG. 2 is a perspective view of the interior of the cover 126. The cover 126 has a ratcheting portion 210 located on an inside surface of the cover 126. The ratcheting portion 210 interfaces with the ratcheting portion 140 on the outside surface of the cover 110. As shown in FIG. 1, the ratcheting portion 140 on the outside surface of the cover 110 is fixed, solid ridges (e.g., triangles or barbs). The ratcheting portion 210 on the inside surface of the cover 126 includes one or more flexible latching fingers 218. The flexible latching fingers 218 may have an attachment point 212 on an interior surface of and toward the distal end of a peripheral wall 220 of the cover 126, and a free end 216 that extends from and is not attached to the peripheral wall of the cover 126. However, in some implementations, the free end 216 may be loosely or movably attached to the peripheral wall 220 of the cover 126. Further, the ratcheting portion 210 may include a latching portion 214, such as an edge or ridge, configured to engage the barbs 142 or triangles of the ratcheting portion 140 on the housing 110. As the ratcheting portion 210 is pushed over each barb 142 of the ratcheting portion 140, each flexible latching finger 218 deflects and then clicks and locks in against each successive barb 142 as it passes over the apex of the barb 142. This provides a ratcheting effect where pushing down the cover 126 relative to the housing 110 will create multiple successive locking latches on each next successive barb 142 of the ratcheting portion 140.

[0012] FIG. 3 is a perspective view of the housing 110 illustrating the ratcheting portion 140 in more detail. The ratcheting portion 140 includes multiple barbs, for example four barbs. As shown, the ratcheting portion 140 includes barbs 310, 312, 314, and 316. Each barb is located in linear succession. Further, each barb includes a surface 320 that protrudes outwardly with a locking edge 322 that is configured to catch against the ratcheting portion 210 of the cover 126. Each barb is solid and may be non-deformable as illustrated by the triangular cross-section 324.

[0013] The ratcheting features (i.e., flexible latching fingers 218) on the cover 126 may extend inward while the ratcheting features (e.g. barbs 310) on the housing 110 may extend outwardly. Although, the ratcheting features may be switched such that the flexible latching fingers extend outward from the housing 110 and the barbs extend inward from the cover 126.

[0014] FIG. 4 is a schematic view of the interaction between the ratcheting portions on the cover 426 and the housing 410. The cover 426 includes ratcheting portion 420 including a plurality of flexible latching fingers 422. The housing 410 includes a ratcheting portion 440. The ratcheting portion 440 includes a plurality of solid stationary barbs 442. Accordingly, as the cover 426 is pressed over the housing 410, the flexible latching fingers 422 deflect, as illustrated by arrow 430, as they slide over the apexes of the solid stationary barbs 442. As the flexible latching fingers 422 pass the apex of a barb 442, the latching finger springs back as illustrated by arrow 450 thereby engaging a retention surface 444 of the corresponding barb 442. As the cover 426 is pushed onto the housing 410 with increasing force, the flexible latching fingers 422 are pushed across more barbs 442, causing increasing retention force between the cover 426 and the housing 410.

[0015] FIG. 5 illustrates an implementation where stationary barbs 442 are located on the inside of the cover 426 and the flexible latching fingers 422 are located on the housing 410. The cover 426 includes ratcheting portion 420 including a plurality of stationary barbs 442. The housing 410 includes a ratcheting portion 440. The ratcheting portion 440 includes a plurality of flexible latching fingers 422. Accordingly, as the cover 426 is pressed over the housing 410, the flexible latching fingers 422 deflect as they slide over the solid stationary barbs 442. As each flexible latching finger 422 passes over the apex of a barb 442, the flexible latching finger 422 springs back, thereby engaging the retention surface of the corresponding barb 442. As the cover is pressed onto the housing 410 with increasing force, the flexible latching fingers 422 are pushed across more barbs 442, causing increasing retention force between the cover 426 and the housing 410. The ratcheting features (e.g. flexible latching fingers 422) on the cover 426 extend inward while the ratcheting features (e.g. barbs 442) on the housing 410 extend outwardly. Although, the ratcheting features may be switched such that the flexible latching fingers 422 extend outward from the housing 410 and the barbs 442 extend inward from the cover 426.

[0016] FIG. 6 is a schematic view of an implementation where the latching fingers 422 are located in a pocket 430 of the cover 426. The barbs 442 are located on an inside surface 460 of the housing 410. The barbs 442 will interact and lock with the flexible latching fingers 422 as described in the previous implementations. Further, other similar implementations are contemplated herein for example, flexible latching fingers 422 may be located on the inside surface 460 of the housing 410 and the barbs 442 may be located in the pocket 430 of the cover 426. The ratcheting features (e.g. barbs 442) on the housing 410 may extend inward while the ratcheting features (e.g. flexible latching fingers 422) on the cover 426 may extend outwardly. Although, the ratcheting features may be switched such that the barbs 442 extend outward from the cover 426 and the flexible latching fingers 422 extend inward from the housing 410.

[0017] In addition, other implementations may be contemplated where the peripheral wall 470 of the cover 426 fits into the cavity 412 of the housing 410 such that the pocket 430 is not used, and ratcheting mechanism 440 on the inside surface of the housing 410 directly engages the ratcheting mechanism 420 on the peripheral wall 470 of the cover 426, as shown in FIG. 7. As such, the barbs 442 or the flexible latching fingers 422 may be located on the outer surface 472 of the peripheral wall 470 of the cover 426, and the corresponding flexible latching fingers 422 or barbs 442 may be located on the inside surface 460, within the cavity 412 of the housing 410.

[0018] FIG. 8 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 500 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 500 includes a first set of columns 510 of ratcheting fingers or barbs that are offset relative to a second set of columns 520 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 500 to lock the cover to the housing with an increased amount of granularity or compression for sealing the sensor assembly.

[0019] As a person skilled in the art will readily appreciate, the above description is meant as an illustration of the principles of this application. This description is not intended to limit the scope or application of the claim in that the assembly is susceptible to modification, variation and change, without departing from the scope of the following claims.

Claims

1. A mountable sensor assembly (100) comprising: a sensor circuit (120); a sensor housing (110) having walls that define a cavity (112) with an opening for receiving the sensor circuit (120); a cover (126) configured to enclose the opening; and a deformable gasket (124) provided to seal between the cover (126) and the housing (110), wherein the cover (126) is configured to interface with the walls of the housing (110) through a ratcheting mechanism that provides a ratcheting effect where pushing down the cover (126) relative to the housing (110) creates multiple successive locking latches; wherein the ratcheting mechanism comprises one or more ratcheting assemblies, where each ratcheting assembly has a first ratcheting portion (140) on the housing (110) and a second ratcheting portion (210) on the cover (126); wherein one of the first ratcheting portion (140) or the second ratcheting portion (210) comprises a plurality of flexible latching fingers (218) that engage a plurality of solid ridges (442) on the other of the first ratcheting portion (140) or the second ratcheting portion (210).

2. The assembly (100) of claim 1, wherein each flexible latching finger (218) has one attached end and one unattached end (216) such that each flexible latching finger (218) deflects from the attached end.

3. The assembly (100) of claim 1 or claim 2, wherein the second ratcheting portion (210) on the cover (126) comprises the plurality of flexible latching fingers (218).

4. The assembly (100) of claim 3, wherein the plurality of flexible latching fingers (218) are on an inside surface of the cover (126).

5. The assembly (100) of claim 3, wherein the plurality of flexible latching fingers (218) are on an outside surface of the cover (126).

6. The assembly (100) of claim 3, wherein the plurality of flexible latching fingers (218) are on the walls of the housing (110).

7. The assembly (100) of claim 6, wherein the plurality of flexible latching fingers (218) are on an inside surface of the walls of the housing (110).

8. The assembly (100) of claim 6, wherein the plurality of flexible latching fingers (218) are on an outside surface of the walls of the housing (110).

9. The assembly (100) of any preceding claim, wherein the plurality of flexible ratcheting fingers (218) comprises a first set of flexible latching fingers and a second set of flexible latching fingers, wherein the first set of flexible latching fingers are offset from the second set of flexible latching fingers.

10. The assembly (100) of claim 9, wherein the first set of flexible latching fingers form a first set of columns and the second set of flexible latching fingers form a second set of columns, and the first set of flexible latching fingers are offset from the second set of flexible latching fingers by rows in the first set of columns being offset from rows in the second set of columns.

11. The assembly (100) of any preceding claim, wherein the plurality of solid ridges comprises a first set of solid ridges and a second set of solid ridges, wherein the first set of solid ridges are offset from the second set of solid ridges.

12. The assembly (100) of claim 11, wherein the first set of solid ridges form a first set of columns and the second set of solid ridges form a second set of columns, and the first set of solid ridges are offset from the second set of solid ridges by rows in the first set of columns being offset from rows in the second set of columns.