Patent Application
20250054666
This application claims the benefit of Korean Patent Application No. 10-2023-0104035, filed on Aug. 9, 2023, which application is hereby incorporated herein by reference.
The present disclosure relates to a magnetorheological (MR) damper.
A damper for a vehicle reacts to the relative speed of a sprung mass and an unsprung mass of the vehicle to generate a damping force, which is a force resisting the relative motion between the sprung mass and the unsprung mass. The damper for a vehicle may be classified into a linear damper and a rotary damper. Currently, the linear damper is widely used.
A vibration system has a resonance determined by the mass and the stiffness of the system, and the amplitude of the resonance is determined by damping. In other words, in a system with large damping, the amplitude at a resonance point is small, whereas in a system with small damping, the amplitude at a resonance point is very large.
The resonance of a vehicle body is usually at a frequency of 1 to 1.5 Hertz (Hz), and the resonance of a vehicle wheel is usually at a frequency of 10 to 15 Hz. The frequency band between the two resonances (1 to 10 Hz) usually corresponds to a band in which humans are very sensitive to the vertical acceleration excitation. When damping in the corresponding frequency band is small, the ride quality is good, and when damping in the corresponding frequency band is large, the ride quality is poor. As a system that provides good riding comfort in the sensitive frequency band has small damping, the system has a large amplitude at the resonance frequency of the vehicle body. The ride quality in the frequency band of 1 to 10 Hz and the amplitude at the resonance frequency of the vehicle body are inversely proportional to each other, having a trade-off relationship.
To compensate such a feature, a variable damping system has been developed. The variable damping system may be classified into two types. One of them is a system configured to control the opening of an orifice using a solenoid or a motor. In this system, the opening of the orifice should be controlled through precise position control, so the system needs a precise micro-position control system. The system uses a method of precisely controlling the position of a spool using a motor or a solenoid valve to adjust the opening of the orifice.
The other type of the variable damping system adjusts damping by changing the characteristics of a fluid using electricity or magnetism. Generally, in changing the characteristics of a fluid, magnetism is used, and a magnetorheological (MR) damper using magnetism is close to practical use as being adopted in many vehicles recently. The MR damper has an orifice through which a fluid flows and has mounted therein an MR coil and an MR core configured to apply a magnetic field around the orifice.
The above information disclosed in this background section is only for enhancement of understanding of the background of embodiments of the present disclosure, and therefore it may contain information that does not form the related art that is already known to a person of ordinary skill in the art.
Korean Patent Publication No. 10-2022-0129190 (Sep. 23, 2022) may provide information related to the technical field of the present disclosure.
Embodiments of the present disclosure can solve problems associated with the related art, and an embodiment of the present disclosure provides an improved MR damper that has a greater efficiency in implementing a damping force for a given volume thereof.
Another embodiment of the present disclosure provides an MR damper capable of efficiently generating a magnetic field.
A further embodiment of the present disclosure provides an MR damper having a reduced frictional force.
The embodiments of the present disclosure are not limited to the foregoing, and other embodiments not mentioned herein will be clearly understood by those of ordinary skill in the art to which the present disclosure pertains (hereinafter, “those skilled in the art”) based on the description below.
The features of embodiments of the present disclosure to perform characteristic functions of the embodiments of the present disclosure to be described later are as follows.
One embodiment of the present disclosure provides an MR damper including a stator including a solenoid coil to which current is applicable, a rotor configured to rotate with respect to the stator, and an orifice formed between the stator and the rotor, the orifice configured to allow fluids sealed in a first chamber and a second chamber defined by the stator and the rotor to communicate with each other.
Another embodiment of the present disclosure provides a method of assembling a stator for an MR damper, the stator having an outer MR core including a first element and a second element, the method including winding a solenoid coil around a bobbin, mounting the second element into the bobbin having the solenoid coil wound therearound, and mounting the bobbin having the second element mounted thereinto to the first element.
Other aspects and preferred embodiments of the present disclosure are discussed infra.
It is to be understood that the term “vehicle” or “vehicular” or other similar terms as used herein are inclusive of motor vehicles in general, such as passenger automobiles including sport utility vehicles (SUVs), buses, trucks, various commercial vehicles, watercraft including a variety of boats and ships, aircraft, and the like, and include hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles, and other alternative fuel vehicles (e.g., fuels derived from resources other than petroleum). As referred to herein, a hybrid vehicle is a vehicle that has two or more sources of power, for example, a vehicle powered by both gasoline and electricity.
The above and other features of embodiments of the present disclosure are discussed infra.
The above and other features of embodiments of the present disclosure will now be described in detail with reference to certain exemplary embodiments thereof illustrated in the accompanying drawings which are given hereinbelow by way of illustration only, and thus are not limitative of the embodiments of the present disclosure, and wherein:
It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various preferred features illustrative of the basic principles of embodiments of the present disclosure. The specific design features of embodiments of the present disclosure, including, for example, specific dimensions, orientations, locations, and shapes, will be determined in part by the particular intended application and usage environment.
In the figures, the reference numbers refer to the same or equivalent parts of the present disclosure throughout the several figures of the drawings.
Descriptions of specific structures or functions presented in the embodiments of the present disclosure are merely exemplary for the purpose of explaining concepts according to the embodiments of the present disclosure, and the embodiments may be implemented in various forms. In addition, the descriptions should not be construed as being limited to the embodiments described herein, and should be understood to include all modifications, equivalents, and substitutes falling within the idea and scope of the embodiments of the present disclosure.
Meanwhile, in the present disclosure, terms such as “first” and/or “second” may be used to describe various components, but the components are not limited by the terms. These terms are only used to distinguish one component from another. For example, a first component could be termed a second component, and similarly, a second component could be termed a first component, without departing from the scope of exemplary embodiments of the present disclosure.
It should be understood that, when a component is referred to as being “connected to” another component, the component may be directly connected to the other component, or intervening components may also be present. In contrast, when a component is referred to as being “directly connected to” another component, there is no intervening component present. Other terms used to describe relationships between components should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.).
Throughout the specification, like reference numerals indicate like components. The terminology used herein is for the purpose of illustrating embodiments and is not intended to limit the present disclosure. In this specification, the singular form includes the plural sense, unless specified otherwise. The terms “comprises” and/or “comprising” used in this specification mean that the cited component, step, operation, and/or element does not exclude the presence or addition of one or more of other components, steps, operations, and/or elements.
Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.
A general linear MR damper has an upper chamber and a lower chamber divided by a piston, and the piston has an orifice formed therein. When the piston moves, a pressure difference is generated between the two chambers, allowing an MR fluid to flow through the orifice. Here, a magnetic field is applied, and then fine particles present in the MR fluid are aligned in a line by the magnetic field, generating a flow of fluid and varying a damping force.
A rotary MR damper includes a stator portion and a rotor portion. As an example, the stator portion may have an annular or cylindrical orifice formed therein, and a solenoid coil may be disposed around the orifice. As another example, an orifice may be formed in a portion where the stator portion and the rotor portion, serving as a shaft, move with respect to each other, and a solenoid coil may be provided as an elongated annular core.
The former case has several problems. For instance, a frictional force may be generated by the relative motion between the stator portion and the rotor portion. Also, the structure thereof is complicated as the orifice, the solenoid coil, and the MR core are disposed inside the stator portion, and the number of structures for generating a required damping force is increased. In the latter case, the portion between the stator portion and the rotor portion where the stator portion and the rotor portion move relative to each other forms the orifice, but due to the solenoid coil having the shape of the elongated annular core, a magnetic field may not be efficiently generated and the number of structures to generate a required damping force may be increased.
For this reason, embodiments of the present disclosure provide an improved MR damper having a simplified structure, having a greater efficiency in implementing a damping force for a given volume thereof, and capable of efficiently generating a magnetic field.
As illustrated in
The housing 10 seals therein an MR fluid. The MR fluid may flow as the rotor 50 rotates. An orifice 40 through which the MR fluid moves is defined between the stator 30 and the rotor 50. Specifically, when the rotor 50 rotates, the MR fluid may flow between a first chamber 70 and a second chamber 90 through the orifice 40. The first chamber 70 and the second chamber 90 are divided by the stator 30 and the rotor 50.
As illustrated in
Referring to
The first element 132 may have a first receiving portion 1132a and a second receiving portion 1132b formed therein. The first receiving portion 1132a and the second receiving portion 1132b may have a groove shape. The first receiving portion 1132a may have a depth greater than that of the second receiving portion 1132b. In one implementation, the second element 232 may be inserted into the first receiving portion 1132a. The bobbin 36 around which the solenoid coil 34 is wound may be mounted on the second element 232.
Referring back to
The solenoid coil 34 may be wound within the outer MR core 32. In one implementation, as illustrated in
Referring to
Continuing to refer to
In one implementation, the vanes 56 may be provided at opposite sides of the stator 30, respectively, with the stator 30 interposed therebetween. Therefore, the first chamber 70 is arranged between any one of the vanes 56 and the stator 30. The second chamber 90 is arranged between the other one of the vanes 56 and the stator 30. The chambers 70, 90 and the vanes 56 may be disposed in the circumferential direction of the MR damper.
As the rotational motion of the shaft 54 is converted to the motion of the vanes 56, the pressure in the two chambers 70, 90, each disposed between the stator 30 and the vanes 56, may change. Accordingly, the MR fluid may flow from the first chamber 70 at a high pressure to the second chamber 90 at a low pressure in a flow direction F. Herein, although the first chamber 70 is described as a high-pressure chamber and the second chamber 90 as a low-pressure chamber, it should be understood that this is merely for clarity of explanation and that the two are interchangeable.
As described above, the orifice 40 is formed between the stator 30 and the rotor 50. Particularly, the orifice 40 may be provided between the stator 30 and the rotor 50 at a radially inner side of the stator 30 or a radially outer side of the rotor 50. Therefore, according to embodiments of the present disclosure, a frictional force that may be generated between the stator 30 and the rotor 50 may be minimized.
Referring to
As is apparent from the above description, embodiments of the present disclosure can provide the following effects.
According to embodiments of the present disclosure, provided is an MR damper that has a greater efficiency in implementing a damping force for a given volume thereof.
Moreover, embodiments of the present disclosure propose an MR damper capable of efficiently generating a magnetic field using a flat core having an “E” shape.
Furthermore, embodiments of the present disclosure provide an MR damper having an orifice formed between a stator and a rotor to reduce a frictional force.
Effects of embodiments of the present disclosure are not limited to what has been described above, and other effects not mentioned herein will be clearly recognized by those skilled in the art based on the above description.
It will be apparent to those of ordinary skill in the art to which the present disclosure pertains that the embodiments of the present disclosure described above are not limited by the above-described embodiments and the accompanying drawings, and various substitutions, modifications, and changes are possible within a range that does not depart from the technical idea of the embodiments of the present disclosure.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2023-0104035 | Aug 2023 | KR | national |
