Patent Application
20210156450
The following description relates to exterior rearview devices such as a rearview camera pod or a rearview mirror that includes a tuned mass damping system, and vehicles including such exterior rearview devices.
Functional performance of a product is essential to customer satisfaction. With respect to exterior rearview devices attached to automobiles, one of the most significant factors of customer satisfaction is the stability of the image that the driver sees in the device as he is checking for objects in his device. This is known as “On Road Vibration Performance” of the device (hereinafter “ORVP”). It is well known that all items have a frequency with which they resonate. With exterior rearview devices it is common knowledge that the higher the resonant frequency of the device, the better the ORVP. It is also common knowledge that the resonant frequency of a device is usually different in the vertical axis compared to the fore/aft axis and the in/out axis.
With all exterior rearview devices, and especially larger exterior rearview devices, the mass of the rearview device may be great and the center of gravity may be outboard. It is also well known that as the mass of an object increases, the resonant frequency decreases. This makes it more difficult to achieve acceptable ORVP on larger exterior rearview devices. In addition, with camera pods and devices which use digital image capturing means to capture a rearview image of the vehicle, stability is even more essential in order to capture a clear digital image.
Another challenge associated with achieving good ORVP with rearview devices, especially in larger vehicles, is the fact that the vehicle itself generates a wide range of resonant vibrations from items such as the engine, tire treads contacting the road surface, stiff high load suspensions, vibrations of the hood or floor-pan, or other larger sheet metal bodies. These resonant vibrations migrate to the rearview device mounting structure of the vehicle door. These resonant vibrations that present themselves in the rearview device mounting structure have a variety of frequencies and amplitudes which all feed into the rearview device structure and ultimately to the rearview device reflective surface. These vibration inputs from the vehicle then combine with the oscillations of the rearview device that are present due to inherent structural characteristics of the exterior rearview device itself and can result in poorer ORVP than desired.
Mass damping is known and mass dampers are commercially available. A typical mass damper includes a structurally rigid mounting plate, a block of material which constitutes the mass, and one or more flexible members that connect the mass with the mounting structure. A mass damper can be designed to specifically have the same resonant frequency regardless of which direction it is checked, while other mass dampers are designed to be more flexible in certain directions and less flexible in other directions resulting in different resonant frequencies in each axis. Previous applications of mass damping in an exterior rearview device involved mounting a mass damper close to the connection point of the reflective element, the display of the rearview device, the camera pod, and/or the structural member of the case. The results of mass damping at these points were not favorable as the added mass of the mass damper would increase the overall mass of the rearview device, and also move the rearview device's center of gravity outboard and in doing so, decrease the base resonant frequency of the rearview device head.
In one aspect, a motor vehicle includes a mating features in a sheet metal of the motor vehicle, and an exterior rearview device fixedly secured to the motor vehicle, the exterior rearview device including a structural base frame that mates to the mating features of the sheet metal at a mounting plane, and a tuned mass damper system secured to the structural base frame adjacent to the mounting plane, the tuned mass damper system including more than one mass damper, where a primary axis of movement of the tuned mass damper system is at least one of substantially parallel with or substantially perpendicular to the mounting plane.
The more than one mass damper may include a first mass damper and a second mass damper.
The first mass damper may be configured to dampen resonant vibrations at a first frequency, and the second mass damper may be configured to dampen resonant vibrations at a second frequency.
The first mass damper may be configured to dampen resonant vibrations along a first axis, and the second mass damper may be configured to dampen resonant vibrations along a second axis.
The tuned mass damper system may include a mass, a mounting shaft that is secured to the structural base frame and extends through the mass, a first spring system and a second spring.
The first mass damper may include the first spring system, the mass and the mounting shaft, and the second mass damper may include the second spring the mass and the mounting shaft.
The first spring system may include a top spring and a bottom spring, and the mass may be flanked by the top spring on a side and the bottom spring on another side, the mass may also contain an opening that houses the second spring.
The tuned mass damper system may include a first mass and a second mass, a first attaching element and a second attaching element, a first shaft formed of flexible material, and a second shaft formed of flexible material.
The first mass damper may include the first mass and the first shaft formed of flexible material, and the second mass damper may include the second mass and the second shaft formed of flexible material.
The first shaft formed of flexible material may include a primary shaft and a secondary shaft, and the first mass may be flanked by the primary shaft on one side and the secondary shaft on another, and the second shaft of flexible material may include a second primary shaft and a second secondary shaft and the second mass may be flanked by the second primary shaft on one side and the second secondary shaft on another.
The tuned mass damper system may be configured to dampen resonant vibrations being generated by the motor vehicle.
In another aspect, a motor vehicle may include a mating features in a sheet metal of the motor vehicle, and an exterior rearview device fixedly secured to the motor vehicle, the exterior rearview device including a structural base frame that mates to the mating features of the sheet metal at a mounting plane, and a tuned mass damper system with more than one mass damper secured to the structural base frame adjacent to the mounting plane, where the tuned mass damper is configured to dampen resonant vibrations being generated by the motor vehicle.
The more than one mass damper includes a first mass damper and a second mass damper.
The first mass damper may be configured to dampen resonant vibrations at a first frequency, and the second mass damper may be configured to dampen resonant vibrations at a second frequency.
The first mass damper may be configured to dampen resonant vibrations along a first axis, and the second mass damper may be configured to dampen resonant vibrations along a second axis.
The tuned mass damper system may include a mass, a mounting shaft that is secured to the structural base frame and extends through the mass, a first spring system and a second spring.
The first mass damper may include the first spring system, the mass and the mounting shaft, and the second mass damper may include the second spring the mass and the mounting shaft.
The first spring system may include a top spring and a bottom spring, and the mass may be flanked by the top spring on a side and the bottom spring on another side, the mass may also contain an opening that houses the second spring.
The tuned mass damper system may include a first mass and a second mass, a first attaching element and a second attaching element, a first shaft formed of flexible material, and a second shaft formed of flexible material.
The first mass damper may include the first mass and the first shaft formed of flexible material, and the second mass damper may include the second mass and the second shaft formed of flexible material.
The first shaft formed of flexible material may include a primary shaft and a secondary shaft, and the first mass may be flanked by the primary shaft on one side and the secondary shaft on the other, and the second shaft of flexible material may include a second primary shaft and a second secondary shaft and the second mass may be flanked by the second primary shaft on one side and the second secondary shaft on the other.
The primary axis of movement of the tuned mass damper system may be at least one of substantially parallel with or substantially perpendicular to the mounting plane.
The foregoing summary, as well as the following detailed description, will be better understood when read in conjunction with the appended drawings. For the purpose of illustration, there is shown in the drawings certain embodiments of the present disclosure. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an implementation of systems and apparatuses consistent with the present invention and, together with the description, serve to explain advantages and principles consistent with the invention.
Before explaining at least one example of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The Figures and written description are provided to teach any person skilled in the art to make and use the inventions for which patent protection is sought. The invention is capable of other embodiments and of being practiced and carried out in various ways. Those skilled in the art will appreciate that not all features of a commercial embodiment are shown for the sake of clarity and understanding. Persons of skill in the art will also appreciate that the development of an actual commercial embodiment incorporating aspects of the present inventions will require numerous implementation-specific decisions to achieve the developer's ultimate goal for the commercial embodiment. While these efforts may be complex and time-consuming, these efforts nevertheless would be a routine undertaking for those of skill in the art having the benefit of this disclosure.
In addition, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting. For example, the use of a singular term, such as, “a” is not intended as limiting of the number of items. Also the use of relational terms, such as but not limited to, “top,” “bottom,” “left,” “right,” “upper,” “lower,” “down,” “up,” “side,” “corner,” are used in the description for clarity in specific reference to the Figures and are not intended to limit the scope of the invention or the appended claims. Further, it should be understood that any one of the features of the invention may be used separately or in combination with other features. Other systems, methods, features, and advantages of the invention will be or become apparent to one with skill in the art upon examination of the Figures and the detailed description. It is intended that all such additional systems, methods, features, and advantages be included within this description, be within the scope of the present invention, and be protected by the accompanying claims.
It should be appreciated that the camera pod 1 is a type of exterior rearview device and may be referred to interchangeably as the rearview device 1. In this example, the camera pod 1 may include one or more cameras 6 and may include a pivot joint between a case assembly 4 and a base assembly 5. The pivot joint may have any of a number of configurations to allow the case assembly 4 to pivot with respect to the base assembly 5.
Other examples of the rearview device 1 may include an exterior rearview or side-view mirror, a rearview or side-view display, a camera/display system, and/or any reflective or non-reflective element which provides a view of the rear or side of a vehicle. U.S. patent application Ser. No. 15/442,143, which is incorporated by reference herein for all purposes, describes an exterior rearview device which is a rearview mirror. For convenience and ease of illustration, the rearview device 1 is illustrated as a camera pod 1. It should be appreciated that the following description is applicable to any example of a rearview device 1 although a camera pod 1 is illustrated.
The rearview device 1 includes the rearview device base assembly 5 having a base frame and a base cover. The rearview device 1 also include the rearview device case assembly 4 having, among other things, a rearview device case and a case frame. In an example, a rearview device 1 may include one or more of a camera 6, a display, or a reflective element such as a mirror. In the examples described below and illustrated in
Referring to
Referring to
Referring to
Referring to
Spring 40 and spring 42 can have a different resultant force than does spring 37, which allows multi-frequency tune mass damper assembly 30 to dampen in response to different frequencies, thereby addressing multiple damping needs. In this regard, first frequency mass damper 35 can dampen a lower frequency, and second frequency mass damper 32 can dampen a higher frequency. In other examples, first frequency mass damper 35 can dampen a higher frequency, and second frequency mass damper 32 can dampen a lower frequency. Spring 40 and 42 can also have the same resultant force as spring 37, which allows first frequency mass damper 35 to dampen in response to the same frequency as mass damper 32.
Referring to
In some examples, flexible members 54 and 56 allow mass 55 to resonate in response to vibration inputs at a first frequency transmitted through the vehicle, and flexible members 51 and 53 allow mass 52 to resonate in response to vibration inputs at a second frequency transmitted through the vehicle. In other examples, flexible members 54 and 56, and 51 and 53 allow both mass 52 and mass 55 to resonate in response to vibration inputs at the same frequency.
Referring to
Mass damping is achieved in this embodiment along two different axis because flexible members 61 and 63 allow mass 62 to resonate in response to vibration inputs transmitted through the vehicle along a first axis, and flexible members 64 and 66 allow mass 65 to resonate in response to vibration inputs transmitted through the vehicle along a second axis. In this embodiment, mass 64 is substantially perpendicular to mass 66, however, it should be appreciated that the embodiment shown is not limited to two perpendicular axis. The two masses can be placed along any two different axis to in order to address multiple damping needs.
There can be more than one frequency inputs effecting the ORVP. The embodiments shown in
It should be appreciated that the embodiments shown in
In an aspect of the above described embodiments and descriptions, a tuned mass damper system 12, 14, 30, 50, 60 is secured to the rearview device base adjacent to a mounting plane 3. If packaging space permits, this can be mounted into the structure of the base frame proper. In another aspect of the above described embodiments and descriptions, a tuned mass damper system 60 is shown secured to the review device base assembly 5. The mass damper system 12, 14, 30, 50, 60 may be designed to have a greater degree of flexibility in the axis or axes that has/have the greatest amount of resonant vibration, or energy input as produced by the vehicle. In this sense, as described, the mass damper system is considered “tuned”. With the mass damper system located as close as possible to the mounting plane 3 of the exterior rearview device, it does not increase the amount of suspended mass at the outboard end of the rearview device. This moves the relative rearview device center of gravity inboard and thus does not decrease the resonant frequency of the rearview device. By being located inboard of and adjacent to the rearview device mounting plane 3 of the door, the mass damper system has the effect of smoothing out the resonant vibrations that are produced by the vehicle that would otherwise be input directly to the rearview device. By smoothing out the vibration inputs into the rearview device, the ORVP of the rearview device is significantly improved.
In an aspect, adjacent to the rearview device mounting plane 3 is preferably within a range of about 2 to about 10 millimeters from the rearview device mounting plane 3; however, this range is not limited thereto. For example, the range includes at least 2 millimeters, at least 3 millimeters, at least 4 millimeters, at least 5 millimeters, at least 6 millimeters, at least 7 millimeters, at least 8 millimeters, at least 9 millimeters, at least 10 millimeters, at most 2 millimeters, at most 3 millimeters, at most 4 millimeters, at most 5 millimeters, at most 6 millimeters, at most 7 millimeters, at most 8 millimeters, at most 9 millimeters, and at most 10 millimeters from the rearview device mounting plane. In a further example, a range from about 0 to about 50 millimeters from the mounting plane 3 is also described.
The apparatus of the present invention has been described above and in the attached drawings; however, modifications will be apparent to those of ordinary skill in the art and the scope of protection for the invention is to be defined by the claims that follow.
This application is a continuation-in-part application of U.S. patent application Ser. No. 16/375,144, filed Apr. 4, 2019, which is a continuation-in-part of U.S. patent application Ser. No. 15/442,143, filed Feb. 24, 2017, each of which is hereby incorporated by reference in its entirety for all purposes.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 16375144 | Apr 2019 | US |
| Child | 17168669 | US | |
| Parent | 15442143 | Feb 2017 | US |
| Child | 16375144 | US |
