Patent ID: 12259017

DETAILED DESCRIPTION OF EMBODIMENTS

The present disclosure describes various embodiments of a device configured to reduce the transmission of noise and vibration frequencies from an internal component to external surfaces. More generally, Applicant has recognized and appreciated that it would be beneficial to provide a suspension system within a device that more accurately and affordably minimizes transmission of acoustic and vibrational energy. The suspension system comprises a rigid support, an operative element such as pump assembly positioned within the rigid support and comprising a drive frequency when the device is in operation, and a suspension comprising a resilient element engaging the rigid support and configured to create a resilient force against one or more degrees of freedom of vibrations generated by the operative element.

The suspension system is configured such that the natural frequency in one or more of the degrees of freedom of the suspension system are tuned into a narrow resonant frequency range, where the resonant frequency is less than the drive frequency. For example, the drive frequency may be less than approximately 85 Hertz (“Hz”), or less than approximately 65 Hz, such as at approximately 10 to 30 Hz although other ranges are possible. The suspension system is configured such that the natural frequency in one or more of the degrees of freedom of the suspension system is approximately 5 Hertz and is thus lower than the drive frequency.

Referring toFIG.1, in one embodiment, is a schematic representation of a basic sound and vibration isolation system within a device10. Device10may represent, for example, an oral irrigator, another handheld device, another consumer device, or any other device with a housing11. In this example, the system comprises a fluid inlet and a fluid outlet, which utilizes a motor and a pump configured to move the fluid from the inlet to the outlet. According to an embodiment, system10comprises one or more resilient elements12configured to suspend at least a portion of the internal components of the system, including the motor and/or pump. The suspension system comprising one or more resilient elements is configured to minimize the transmission of vibration and sound from the internal operative element, such as a motor or pump, to the housing, thereby improving the user experience. Accordingly, resilient elements12can be any resilient element configured to isolate and/or dampen sound and vibration, including but not limited to springs, magnets, elastomers, and many other resilient elements.

Referring toFIG.2, in one embodiment, is a schematic representation of an assembled operative element16. In this embodiment the operative element is a pump comprising an inlet18and an outlet20. The device comprises this operative element within a house of the device, which pumps fluid from the inlet to the outlet. According to just one embodiment of many possible embodiments, the operative element pumps fluid from a fluid reservoir at low pressure through the pump into a high pressure line exiting from the outlet. The operative element may operate at a wide range of different frequencies, and in this embodiment the operative element functions at less than approximately 85 Hz, or less than approximately 65 Hz, such as at approximately 10 to 30 Hz although other ranges are possible. In this device, the primary source of noise and vibration will be the fluid path and the pump and drive train. The pump and drive train will be the source for most of this vibration creating repeatable sound/vibration impulses of a fixed frequency that will also excite harmonics. Transmission of this vibration to external surfaces generates the majority of sound heard by a user, and these primary sound/vibration sources then transmit to secondary sources. These secondary sources are energized from the principal frequency and/or harmonics that move parts exposed to the user/external air that radiate sound vibrations from the principal forces to the user. Secondary sound sources can be magnified by resonances and intermittent contacts. Secondary sound sources with large surface areas generate sound much more efficiently for a given vibration.

Functioning of the suspension system results in the generation of one or more natural frequencies at which the system can resonate of which the first six lowest frequencies are considered primary modes. A primary mode frequency may be, for example, the frequency that excites the system and causes it to vibrate or move in those modes. An embodiment of the operative element may comprise, for example, six primary modes which are the first three translation modes and three rotational modes. Translation is when the center of gravity of the suspended operative element moves in a line, and rotation is when the suspended operative element rotates around a pole which would conduce with the center of gravity of the suspended operative element. Depending on the embodiment of the device and/or operative element, one or more modes may not be present.

According to an embodiment, the operative element of a device may operate at a specific frequency range such as approximately 10 to 30 Hz, among many other possible ranges. To avoid resonant effects, the natural frequencies of the suspended system need to be either below or above this range. Natural frequencies are determined from the mass of the operative element, and the stiffness of the suspension. Since the mass of the operative element is essentially fixed, the stiffness is the primary parameter that can be varied to tune the suspension. According to an embodiment, the suspension system is configured to limit movement of the pump assembly to less 10 mm in any direction. The non-linear spring rate allows for a soft suspension when normal oriented and a more rigid suspension when oriented in other directions to prevent banging that makes the device seem inoperable while allowing it to be small in size.

According to an embodiment, a suspension system for a device with an operative element may have several requirements for sound and vibration reduction, as well as other design specifications. According to an embodiment, the suspension system should be designed or structured to operate such that the first six natural frequencies of the suspension system and operative element are close to the operative element operating frequencies, but far enough away from the operative element operating frequencies to avoid resonance. It may also be desirable to ensure that the suspension system is affordable, fits within the provided housing, and is robust enough to survive normal use including dropping.

High damping by the suspension system will increase the transmissibility of vibration through the suspension and is not desirable in most embodiments. For example, high or critical damping means that the system loses energy quickly and this lost energy is transmitted through the suspension to the external housing. A non-critically damped system maintains more of its energy for a longer time. Critically damped means the system would not oscillate more than one cycle after being excited.

Referring toFIG.3, in one embodiment, is a schematic representation of an assembled suspension system22with an operative element16, in which the operative element is suspended within the suspension system. The natural frequency in one or more of the degrees of freedom of the suspension system are tuned into a narrow resonant frequency range by the suspension, and the resonant frequency of the assembled suspension system22is less than the drive frequency of operative element16. AlthoughFIG.3depicts an embodiment of a suspension system22and an operative element16, this embodiment is a non-limiting example. The operative element16may be any other operative element16, and the suspension system may be otherwise structured or configured such that the natural frequency in one or more of the degrees of freedom of the suspension system are tuned into a narrow resonant frequency range by the suspension and the resonant frequency of the assembled suspension system is less than the drive frequency of the operative element.

According to this embodiment, suspension system22comprises a rigid support24. The rigid support is an interface between the operative element16and one or more elements of the suspension, with the housing or other fixed structure within the device. For example, the rigid support24supports the operative element16and one or more elements of the suspension, and facilitates the positioning of the operative element16and the other elements of the suspension in order to minimize sound and vibration of the operative element by tuning its natural frequencies into a narrow resonant frequency range less than the drive frequency of the operative element. Rigid support24may be composed of any material sufficient to support the weight of at least the operative element16, as well as sufficiently resist the forces exerted by the operative element16and restrict excessive movement, and avoid deformation over time.

Although not shown, the suspension system further includes a resilient element26positioned between the rigid support24and the operative element16. The resilient element26is an interface between the rigid support and the operative element, and supports the weight of the operative element. Resilient element26may be any component, device, or mechanism that exerts a bias and/or absorbs energy. For example, the resilient element may be one or more of any type of spring, magnet, polymer, or other material or structure that exerts a bias and/or absorbs energy. For example, in this embodiment, resilient element26is a spring that exerts a bias against the rigid support and/or operative element, and absorbs energy from the operative frequencies generated by the operative element. According to an embodiment, the resilient element is configured to create a resilient force against all six degrees of freedom of vibrations generated the operative assembly.

In some embodiments, suspension system22may further comprise a second resilient element28positioned between the rigid support24and the operative element16and configured to further minimize and/or absorb energy from the operative frequencies generated by the operative element. Thus, the first and second resilient elements minimize sound and vibration of the operative element to tune the natural frequencies into a narrow resonant frequency range less than the drive frequency of the operative element.

AlthoughFIG.3depicts an embodiment of a second resilient element28, this embodiment is a non-limiting example. In this example, the second resilient element28is an interface between the rigid support and the operative element. Resilient element28may be any component, device, or mechanism that exerts a bias and/or absorbs energy. For example, the resilient element may be one or more of any type of spring, magnet, polymer, or other material or structure that exerts a bias and/or absorbs energy. For example, in this embodiment, resilient element28is a natural or synthetic polymer having elastic properties, such as an elastomer. For example, a resilient element may comprise a silicone material, among other possible materials. The second resilient element28also comprises an opening44that allows a portion of the operative element16to extend through. In other embodiments the second resilient element28may be positioned above the operative element.

Referring toFIG.4, in one embodiment, is an exploded view of a portion of a device comprising a suspension system configured to tune the natural frequencies of the system into a narrow resonant frequency range less than the drive frequency of the operative element. AlthoughFIG.4depicts a specific embodiment of this portion of a device, this embodiment is a non-limiting example. The suspension system comprises a rigid support24, first resilient element26, and optionally a second resilient element28, configured to contain operative element16.

Referring toFIG.5is a series of schematic representations depicting six natural frequencies of an embodiment of the suspension system. The representations show the second resilient element28of the suspension system relative to a portion of the operative element16. The representations depict forces exerted on, for example, the second resilient element28by the natural frequencies.

Referring toFIG.6, in one embodiment, is a rigid support24. The rigid support comprises three extensions34extending from the base36, each ending in a prong38configured to fit and lock into an interlocking prong holder40of the second resilient element (shown inFIG.7). The rigid support24may also comprise a receiving portion configured to position the first resilient element (not shown). The rigid support may be composed of any material, including metal, plastic, or any other polymer. The rigidity of the rigid support is another configurable component of the suspension system. In other words, the rigidity of the rigid support can be selected to further minimize vibrations and/or noise generated and transmitted by the operative element.

Referring toFIG.7, in one embodiment, is a schematic representation of a suspension system22with a rigid support24and a second resilient element28, without the first resilient element26. The rigid support24comprises a base36, extensions34, and prongs38, and a first resilient element receiving portion. The second resilient element28comprises interlocking prong holders40and an opening44that allows a portion of the operative element to extend through. In this embodiment, the rigid support and second resilient element are assembled without the operative element. Each of the prongs38have been extended through the interlocking prong holders40and the prongs now function to hold the rigid support and second resilient element interlocked.

Referring toFIG.8, the natural frequencies of the suspension system described or otherwise envisioned herein are lower than the fundamental frequencies of the operative element, thus significantly reducing more vibration and noise than prior art systems. This is an ideal scenario as all the pump frequencies are in the isolation portion of the plot (T<0.1). To achieve this, the suspension system described or otherwise envisioned herein can take many configurations. The rigid support and first resilient element can be structured or otherwise configured in shape, material, and/or relationship in a wide variety of ways to result in a final structure such that the natural frequency in one or more of the degrees of freedom of the suspension system are tuned into a narrow resonant frequency range by the suspension, where the resonant frequency is less than the drive frequency. Among many other configurations, the dimensions and other parameters of the resilient elements may be adjusted, including but not limited to size, shape, weight, diameter, and thickness of spring coils when it is a spring, strength of magnets when it is a magnet, and more.

According to an embodiment, the flexible suspension elements are very small and soft to achieve a 5 Hz natural frequency. Although very soft flexible elements may have negative effects, these negative effects may be addressed by further design or configuration of the suspension system. Examples of effects that might require addressing include that the operative assembly may have the ability to shift within the suspension system by roughly 10 mm in any direction. Further, the suspension system may be large while the flexible elements may be very small, which might not be robust with normal wear and tear.

To address these issues, the system may utilize a non-linear spring system to keep the frequency low without taking significant space or having significant internal displacement during movement and handling that may be experienced as negative by the user. These non-linear springs can take the form of mechanical designs with over stable position, magnetic, hybrid springs, conical coil, dual pitch, and more. Alternately, a hybrid design with a linear spring with a resonance in the 40-60 Hz range except for rotation which could be non-linear and is the principal direction of vibration from the pump. According to one embodiment, utilizing a suspension with a natural frequency in the 5 Hz range isolates vibrations that are easily heard, reducing A-weighted sound power to a maximum extent.

According to one embodiment the spring rate of the first resilient element is non-linear with an increasing spring rate from the nominal position. Further, the spring rate may not be high enough with excursion of the pump under normal operation to have a resonant frequency of 5 Hz.

The non-linear spring system26can take many different forms, including but not limited to one or more magnets. Referring toFIG.9, in one embodiment, is a schematic representation of a portion of a magnet system utilized as a non-linear spring. In this embodiment and variations thereof, there is a configuration of magnets of the same pole on a surface of an operative element16(not shown) and on an opposing surface of the rigid structure24. The magnets on the operative element surface are directly opposing the magnets on the surface of the rigid structure, and since they have the same pole facing toward each other, there is a repulsive force. The two poles may both be North or South. As discussed herein, the magnetic repulsion could be replaced by non-linear mechanical springs such as conical coil, barrel spring, dual-pitch coil, and other non-linear springs, as well as combinations thereof. According to an embodiment, the non-linear resilient element may comprise plastic and/or metal.

Referring toFIGS.10and11, in various embodiment, are schematic representations of non-linear springs that may be utilized in the suspension system to tune the natural frequency in one or more of the degrees of freedom of the suspension system into a narrow resonant frequency range by the suspension, such that the resonant frequency is less than the drive frequency. The non-linear springs include a conical and/or tapered spring inFIG.10and two different dual-pitch compression springs inFIG.11.

Referring toFIG.12, in one embodiment, is a schematic representation of a non-linear spring that can be utilized in the suspension system described or otherwise envisioned herein. The non-linear spring comprises three long resilient arms configured to provide configured to create a resilient force against one or more degrees of freedom of vibrations generated by the pump assembly. The short vertical leg on the end of each arm provides additional torsion that reduces Z stiffness. Each of the resilient arms is a distinct spring, and thus the resilient structure comprises three or more metal springs in tension supporting the operative element.

The non-linear spring also comprises a platform on which the operative assembly may directly or indirectly rest. The non-linear spring may be composed of any material configured to provide the desired resilience, including but not limited to metal. The design of the non-linear spring inFIG.12has natural frequencies below 5 Hz in the X, Y, and Z directions.

Referring toFIGS.13-15, according to an embodiment, are schematic representations of difference views of a non-linear spring that can be utilized in the suspension system described or otherwise envisioned herein. The non-linear spring comprises three staircase arms configured to create a resilient force against one or more degrees of freedom of vibrations generated by the pump assembly. The staircase arrangement of leaf spring elements are connected in a plurality of different orientations to create a compact resilient element. Instead of a design with just bends in the arms, the staircase arrangement of the spring arms minimizes the size of the flat pattern. These non-linear springs can be designed to have natural frequencies below 5 Hz in the X, Y, and Z directions.

Referring toFIG.16is a schematic representation of a non-linear spring that can be utilized in the suspension system described or otherwise envisioned herein. The non-linear spring comprises three resilient arms configured to provide configured to create a resilient force against one or more degrees of freedom of vibrations generated by the pump assembly.

Referring toFIG.17is a bottom view of a device10with a suspension system. The suspension system comprises a non-linear spring26with staircase arms. In this embodiment, the spring arms are shorter and the bend angles are reduced. The shallower bend angles make the suspension shorter and keep the overall spring constant lower.

All definitions, as defined and used herein, should be understood to control over dictionary definitions, definitions in documents incorporated by reference, and/or ordinary meanings of the defined terms.

The indefinite articles “a” and “an,” as used herein in the specification and in the claims, unless clearly indicated to the contrary, should be understood to mean “at least one.”

The phrase “and/or,” as used herein in the specification and in the claims, should be understood to mean “either or both” of the elements so conjoined, i.e., elements that are conjunctively present in some cases and disjunctively present in other cases. Multiple elements listed with “and/or” should be construed in the same fashion, i.e., “one or more” of the elements so conjoined. Other elements may optionally be present other than the elements specifically identified by the “and/or” clause, whether related or unrelated to those elements specifically identified.

As used herein in the specification and in the claims, “or” should be understood to have the same meaning as “and/or” as defined above. For example, when separating items in a list, “or” or “and/or” shall be interpreted as being inclusive, i.e., the inclusion of at least one, but also including more than one, of a number or list of elements, and, optionally, additional unlisted items. Only terms clearly indicated to the contrary, such as “only one of” or “exactly one of,” or, when used in the claims, “consisting of,” will refer to the inclusion of exactly one element of a number or list of elements. In general, the term “or” as used herein shall only be interpreted as indicating exclusive alternatives (i.e. “one or the other but not both”) when preceded by terms of exclusivity, such as “either,” “one of,” “only one of,” or “exactly one of.”

As used herein in the specification and in the claims, the phrase “at least one,” in reference to a list of one or more elements, should be understood to mean at least one element selected from any one or more of the elements in the list of elements, but not necessarily including at least one of each and every element specifically listed within the list of elements and not excluding any combinations of elements in the list of elements. This definition also allows that elements may optionally be present other than the elements specifically identified within the list of elements to which the phrase “at least one” refers, whether related or unrelated to those elements specifically identified.

It should also be understood that, unless clearly indicated to the contrary, in any methods claimed herein that include more than one step or act, the order of the steps or acts of the method is not necessarily limited to the order in which the steps or acts of the method are recited.

In the claims, as well as in the specification above, all transitional phrases such as “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” “holding,” “composed of,” and the like are to be understood to be open-ended, i.e., to mean including but not limited to. Only the transitional phrases “consisting of” and “consisting essentially of” shall be closed or semi-closed transitional phrases, respectively.

While several inventive embodiments have been described and illustrated herein, those of ordinary skill in the art will readily envision a variety of other means and/or structures for performing the function and/or obtaining the results and/or one or more of the advantages described herein, and each of such variations and/or modifications is deemed to be within the scope of the inventive embodiments described herein. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and/or configurations will depend upon the specific application or applications for which the inventive teachings is/are used. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific inventive embodiments described herein. It is, therefore, to be understood that the foregoing embodiments are presented by way of example only and that, within the scope of the appended claims and equivalents thereto, inventive embodiments may be practiced otherwise than as specifically described and claimed. Inventive embodiments of the present disclosure are directed to each individual feature, system, article, material, kit, and/or method described herein. In addition, any combination of two or more such features, systems, articles, materials, kits, and/or methods, if such features, systems, articles, materials, kits, and/or methods are not mutually inconsistent, is included within the inventive scope of the present disclosure.