Patent Application
20180130619
The present disclosure generally relates to a switch, and more particularly to a rotary type switch.
Switches of various kinds are used in many settings to make electrical connections. One type of switch is a rotary switch. Rotary switches can be used in many situations. For example, rotary switches are commonly used in control systems for automobiles or other vehicles. Rotary switches are also used in other types of control systems.
This background discussion is intended to provide information related to the present disclosure which is not necessarily prior art.
One aspect of the present disclosure is directed to a rotary switch including an actuator support and an actuator. The actuator support includes a housing. The housing has an interior. Electrical circuitry in the housing interior is provided for making at least one electrical connection. The actuator is operatively connected to the electrical circuitry and rotatable with respect to the actuator support for making the at least one electrical connection. An arcuate gap is between the actuator and the actuator support. A gasket is in the arcuate gap and in engagement with the actuator and actuator support for blocking ingress of contaminants to the housing interior. The gasket is formed separately from the actuator and the actuator support and comprises resiliently compressible material.
Another aspect of the present disclosure is directed to a rotary switch including an actuator support and an actuator. The actuator support includes a housing. The housing has an interior. Electrical circuitry in the housing interior is provided for making at least one electrical connection. The actuator is operatively connected to the electrical circuitry and rotatable with respect to the actuator support for making the at least one electrical connection. An inlet is between the actuator support and the actuator. An arcuate lubricant reservoir is between the actuator and the actuator support and is configured for holding a lubricant for blocking ingress of contaminants to the housing interior from the inlet.
Yet another aspect of the present disclosure is directed to a rotary transfer case selector switch. The switch includes a housing having an interior. Electrical circuitry in the housing interior is provided for making at least one electrical connection. A knob extending from the housing includes a post and a wheel. The wheel is operatively connected to the electrical circuitry and rotatable about the post for making the at least one electrical connection. The knob has an arcuate gap between the post and the wheel. A gasket formed separately from the post and the wheel is positioned between the post and the wheel in the arcuate gap for blocking ingress of contaminants to the housing interior through the arcuate gap. The gasket comprises a resiliently compressible material.
This summary is not intended to identify essential features of the disclosed switch and is not intended to limit the scope of the appended claims. Various other aspects and advantages of the switch of the present disclosure will be apparent from the following detailed description and the accompanying drawings.
Corresponding reference characters indicate corresponding parts throughout the drawings. The drawings are not intended to limit the scope of the appended claims to the specific illustrated embodiment. The drawings are not necessarily to scale.
The following detailed description of embodiments of switches references the accompanying figures. The description is intended to describe aspects in sufficient detail to enable those with ordinary skill in the art to make and use the claimed switch. Other embodiments can be utilized and changes can be made without departing from the scope of the appended claims. The following description is, therefore, not limiting. The scope of the present invention is defined only by the appended claims, along with the full scope of equivalents to which the claims are entitled.
In this description, references to “one embodiment”, “an embodiment”, or “embodiments” mean that the feature or features referred to are included in at least one embodiment. Separate references to “one embodiment”, “an embodiment”, or “embodiments” in this description do not necessarily refer to the same embodiment and are not mutually exclusive unless so stated. Specifically, a feature, structure, step, etc. described in one embodiment can also be included in other embodiments, but is not necessarily included. Thus, particular implementations of the claims can include a variety of combinations and/or integrations of the embodiments disclosed herein.
Referring to the drawings,
As shown in
Referring to
Still referring to
The wheel 18 generally includes a hub 44 and a grip 46. The hub 44 is generally tubular and serves as a support for the grip 46. The hub 44 is formed of injection molded plastic or another suitable material. The grip 46 forms a generally cylindrical side wall of the knob 14. In the illustrated embodiment, the grip 46 is formed of a different material than the hub 44. The hub 44 serves as a generally rigid substrate onto which the grip 46 is overmolded. The grip is formed of a polyolefin elastomer, thermoplastic vulcanizate, or another suitable material. Desirably, the grip 46 is softer than the hub 44 and provides a soft touch feel for the user. In other embodiments, the grip 46 is formed of the same material as the hub 44. Desirably, the exterior surface of the grip 46 is textured (e.g., includes a plurality of nubs, as shown in
As will be described in further detail below, in the illustrated embodiment, the wheel 18 includes an overmolded layer 50 (
The wheel 18 includes an indicator 52 (
The wheel 18 can be rotated by a user to rotate the rotor 30 and thus actuate the switch 10. The wheel 18 is operatively connected to the rotor 30 such that the rotor rotates conjointly with the wheel when a user applies rotational force to the grip 46. As shown in
The wheel 18 and rotor 30 can be referred to collectively as an actuator 60 of the switch 10. The actuator 60 rotates with respect to the post 16 and housing 12 for actuation of the switch. One or more springs 62 (broadly “biasing elements”) (
The post 16 and the housing 12 can be collectively referred to as an actuator support 64 of the switch 10. The actuator 60 is rotatable with respect to the actuator support 64 for actuating the switch. In the illustrated embodiment, the housing 12 and post 16 remain stationary, and the actuator 60 rotates with respect to the housing and post. However, in other embodiments, components of the actuator support 64 can be movable yet still be considered an actuator support with respect to the actuator 60. For example, it is contemplated that the face 34 could serve as a movable push button or be selectively rotatable independent from the wheel 18.
The switch 10 includes two locations that are potentially prone to ingress of contaminants such as particulates and liquids. In particular, the switch 10 has a first annular passage 70A between the wheel 18 and the post 16 and a second annular passage 70B between the wheel and the housing 12. Both passages 70A, 70B serve as potential passageways for contaminants to enter the interior of the housing 12. Liquid entering the switch 10 can be particularly problematic in adversely affecting the electrical circuitry and associated components in the switch, potentially causing failure of the switch. Accordingly, it is desirable to block such contaminants from entering the switch 10.
As shown in
A first form of defense against contaminants is an annular O-ring 80 (broadly “gasket”) positioned between the wheel 18 and the post 16. The O-ring 80 is positioned in an annular gap forming part of the annular passage. More specifically, in the illustrated embodiment, the overmolded layer 50 and the face support 36 define respective annular recesses for receiving the O-ring. The annular recesses have cross-sectional shapes corresponding to the cross-sectional shape of the O-ring. Collectively, the recesses provide the annular passage with an annular cavity having a rounded, more specifically substantially circular, cross-sectional shape for housing the O-ring 80. The O-ring is slightly oversized in thickness (e.g., by about 0.2 mm) for providing a sealing interference fit against both the overmolded layer 50 and the face support 36. The O-ring 80 engages and is slightly resiliently compressed by the wheel 18 and the post 16 when installed in the annular cavity, which enhances the seal made by the O-ring. In use, the O-ring may or may not rotate with the wheel 18. The O-ring is not fixedly connected to the post 16 to prevent rotation of the O-ring with the wheel and is not fixedly connected to the wheel 18 to cause rotation of the O-ring with the wheel.
A second form of defense against contaminants is an annular reservoir 82 containing lubricant (e.g., grease). In the illustrated embodiment, the wheel 18 and the post 16 are shaped to provide the annular passage with the annular lubricant reservoir downstream from the O-ring 80. The lubricant reservoir 82 is bounded by the overmolded layer 50, the face support 36, and the O-ring 80. Desirably, the lubricant reservoir 82 contains a lubricant suitable for acting as a seal against liquids that might pass the O-ring 80. For example, a lubricant such as PTFE thickened perflouropolyether grease can be used. Desirably, the lubricant exhibits minimal change in viscosity over a wide range of temperatures in which the switch 10 is expected to be used.
A third form of defense is an annular rib 84 downstream from the lubricant pocket. The rib 84 is formed as part of the overmolded layer 50 of the wheel 18. Desirably, the rib 84 is slightly oversized (e.g., by about 0.2 mm) to provide an interference fit with the side of the post 16. In the assembled state of the switch 10, the rib 84 engages and is resiliently compressed against the side of the face support 36 to provide enhanced sealing against the post 16.
Now referring to
It will be appreciated that components described above as being annular can broadly be referred to as arcuate in the sense that an annular shape includes several arcuate segments. Accordingly, for example, the annular passages 70A, 70B can be referred to as arcuate passages 70A, 70B, and the annular lubricant reservoir 82 can be referred to as an arcuate lubricant reservoir 82, etc. Moreover, it will be appreciated that the annular (or arcuate) components extend around the axis of rotation of the wheel 18.
Referring to
Rotary switches constructed according to the embodiment disclosed herein have been tested and found to be satisfactory in preventing liquid and other contaminates from entering the switch at the first and second annular passages 70A, 70B. However, it will be understood that features disclosed herein can be omitted and/or modified without departing from the scope of the present invention. For example, it is contemplated that an O-ring and/or lubricant reservoir can be provided in the second annular passage in essentially the same fashion as provided in the first annular passage.
When introducing elements of aspects of the invention or the embodiments thereof, the articles “a,” “an,” “the,” and “said” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.
Although examples of the features claimed below have been described in various embodiments above, it will be understood that equivalents can be employed and substitutions can be made without departing from the scope of the claims.
