Patent Application
20210379949
The present invention generally relates to a vibration attenuation assembly for a vehicle. More specifically, the present invention relates to vibration attenuation assembly that includes a strut weight attached to an upper end of a vehicle strut assembly.
All structures have one or more resonance frequencies. A resonance frequency is a natural frequency of vibration present m any object or structure.
One object of the present disclosure is to provide a vehicle body structure with a simple means for attenuation of a structure to reduce or eliminate vibrations of that structure.
Another object of the present disclosure is to provide a vehicle strut assembly with a weight that attenuates the natural vibration frequencies of the vehicle strut assembly.
In view of the state of the known technology, one aspect of the present disclosure is to provide a vibration attenuation assembly with a strut weight configured to attenuate resonant frequency of a vehicle strut assembly. The strut weight has an upper surface and a lower surface. The strut weight has a rod receiving opening that extends from a central area of the upper surface to the lower surface. The upper surface has a conical shape.
Referring now to the attached drawings which form a part of this original disclosure:
Selected embodiments will now be explained with reference to the drawings. It will be apparent to those skilled in the art from this disclosure that the following descriptions of the embodiments are provided for illustration only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.
Referring initially to
The vehicle 10 further includes a vehicle body structure 15 that includes a front fender 16 that partially conceals a wheel well 18. As shown in
As shown in
As shown in
As shown schematically in
A description of the strut assembly 12 is now provided with specific reference to
The hollow support member 40 defines the lower end 12b of the strut assembly 12 and is attached to the steering knuckle 32, as mentioned above. The lower spring seat 42 is welded to or otherwise fixedly attached to the hollow support member 40. A lower end of the shock absorber 44 is fitted within the hollow support member 40 and is attached thereto. The shock absorber 44 has a shaft 44a that moves relative to the hollow support member 40 in response to the vehicle 10 rolling over uneven surfaces in a conventional manner. The upper end of the shaft 44a extends upward through respective openings in the flexible bumper boot 46, the upper spring seat 50, the strut bearing 52, the insulator strut mounting 54, the sleeve 56, the strut attachment structure 28, the upper insulator stopper 58, the strut attachment fastener 60 and the strut weight 62.
The flexible bumper boot 46 has a lower end that attaches to an outer surface of an upper end of the hollow support member 40. The flexible bumper boot 46 has an upper stopper end that is retained within the upper spring seat 50. The coil spring 48 is installed between the lower spring seat 42 and the upper spring seat 50.
The insulator strut mounting 54 is basically a lower insulator stopper that can be manufactured with a metallic support surrounded by a compressible elastic material, or alternatively can be made completely from a compressible elastic material.
The upper insulator stopper 58 includes a metallic cup shaped portion 66 and an outer annular ring portion 68 that includes elastic cushion elements 70. The metallic cup shaped portion 66 extends through the single opening 28c of the strut attachment structure 28 and overlays and contacts the sleeve 56. The metallic cup shaped portion 66 also contacts a portion of the insulator strut mounting 54. The outer annular ring portion 68 extends radially outward over the upper surface 28a of the strut attachment structure 28. The elastic cushion elements 70 contact the upper surface 28a of the strut attachment structure 28. Hence, the strut attachment structure 28 is clamped between the upper insulator stopper 58 and the insulator strut mounting 54 (the lower insulator stopper).
The sleeve 56 overlays and contacts a portion of the bearing 56. The bearing overlays and contacts a portion of the upper spring seat 50.
A description of the strut weight 62 is now provided with reference to
The strut weight 62 has an annular disc-like shape with a central opening 72, an upper surface 74 with a counterbore 76 axially aligned with the opening 72 and a lower surface 78. The upper surface 74 has a conical shape tapering downward moving towards an outer radial edge thereof. The opening 72 extends from the upper surface 74 to the lower surface 78. The counter bore 76 extends approximately half-way down the opening 72 and is axially aligned with the opening 72. The counter bore 76 is dimensioned to receive the strut attachment fastener 60.
As shown in
The strut attachment fastener 60 is basically a threaded nut that is configured and dimensioned to thread onto threads formed along the upper end of the shaft 44a of the shock absorber 44. Once tightened, the strut attachment fastener 60 is disposed within the counterbore 76 of the strut weight 62. Further, once tightened, the strut attachment fastener 60 presses the central portion 84 of the strut weight 62 against the metallic cup shaped portion 66 of the upper insulator stopper 58. The tightening force of the strut attachment fastener 60 further presses the metal cup shaped portion 66 against the upper surfaces of the insulator strut mounting 54 and the sleeve 56. Hence, vertical movement of the upper end 12a of the strut assembly 12 is limited by the strut attachment structure 28 (upper panel of strut tower 20) being clamped between the insulator strut mounting 54 (the lower rebound stopper 54) and the upper insulator stopper 58 (the rebound stopper 58).
As shown in
A section of the upper insulator stopper 58 is at least partially disposed within the concaved area 82 of the lower surface 78 of the strut weight 62, as shown in
A description of the vibration attenuation assembly 14 is now provided. As shown in
In accordance with the principles of basic physics and basic engineering principles, all structures have resonance frequencies. Specifically, if a structure is exposed to a vibration at the resonance frequency of the structure, the structure will also vibrate and can amplify that vibration due to mechanical resonance.
Mechanical resonance is the tendency of a mechanical system to absorb more energy when the frequency of its oscillations matches the system's natural frequency of vibration (resonant frequency) than it does at other frequencies. It is advantageous to design structures to ensure the mechanical resonance frequencies of vehicle component parts do not match driving vibrational frequencies of motors or other oscillating parts of the vehicle in order to improve the vehicle operating experience and avoid premature failure.
Each portion of the vehicle body structure 15, including the strut attachment structure 18 has at least one resonance frequency and can have multiple resonance frequencies. Specifically, the strut tower 20 (including the strut attachment structure 28) of the vehicle body structure 15 defines at least a first resonant frequency. The strut assembly 12 defines a second resonant frequency. Depending on the design of the vehicle 10, the first resonance frequency of the strut tower 20 can be close to or the same as the second resonant frequency of the strut assembly 12 (in the absence of the strut weight).
When installed to the strut assembly 12 in a manner described above, the strut weight 62 changes the second resonance frequency of the strut assembly 12 to a different resonance frequency, in order to ensure that the new resonance frequency of the strut assembly 12 with the strut weight 62 differs from the first resonance frequency of the strut attachment structure 28 (and possibly the vehicle body structure 15). The strut weight 62 can be configured with a predetermined mass that changes and attenuates the second resonance frequency of the strut assembly 12 in order to prevent propagation of mechanical vibrations in the strut tower 20 and the strut assembly 12 when operating the vehicle 10.
Hence, the strut weight 62 is configured to attenuate resonant frequency of the strut assembly 12 when installed to the upper portion 12a of the strut assembly 12.
The various features of the vehicle 10, other than the vibration attenuation assembly 14 (and strut weight 62) are conventional components that are well known in the art. Since these features of the vehicle 10 are well known in the art, these structures will not be discussed or illustrated in detail herein. Rather, it will be apparent to those skilled in the art from this disclosure that the components can be any type of structure and/or programming that can be used to carry out the present invention.
In understanding the scope of the present invention, the term “comprising” and its derivatives, as used herein, are intended to be open ended terms that specify the presence of the stated features, elements, components, groups, integers, and/or steps, but do not exclude the presence of other unstated features, elements, components, groups, integers and/or steps. The foregoing also applies to words having similar meanings such as the terms, “including”, “having” and their derivatives. Also, the terms “part,” “section.” “portion,” “member” or “element” when used in the singular can have the dual meaning of a single part or a plurality of parts. Also as used herein to describe the above embodiment, the following directional terms “forward”, “rearward”, “above”. “downward”, “vertical”, “horizontal”, “below” and “transverse” as well as any other similar directional terms refer to those directions of a vehicle equipped with the vibration attenuation assembly. Accordingly, these terms, as utilized to describe the present invention should be interpreted relative to a vehicle equipped with the vibration attenuation assembly.
The term “configured” as used herein to describe a component, section or part of a device includes hardware and/or structure that is constructed to carry out the desired function.
The terms of degree such as “substantially”, “about” and “approximately” as used herein mean a reasonable amount of deviation of the modified term such that the end result is not significantly changed.
While only selected embodiments have been chosen to illustrate the present invention, it will be apparent to those skilled in the art from this disclosure that various changes and modifications can be made herein without departing from the scope of the invention as defined in the appended claims. For example, the size, shape, location or orientation of the various components can be changed as needed and/or desired. Components that are shown directly connected or contacting each other can have intermediate structures disposed between them. The functions of one element can be performed by two, and vice versa. The structures and functions of one embodiment can be adopted in another embodiment. It is not necessary for all advantages to be present in a particular embodiment at the same time. Every feature which is unique from the prior art, alone or in combination with other features, also should be considered a separate description of further inventions by the applicant, including the structural and/or functional concepts embodied by such features. Thus, the foregoing descriptions of the embodiments according to the present invention are provided for illustration only, and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.
