Speed reducer and independent steering system comprising same

Abstract

A decelerator and an independent steering system including the decelerator, the decelerator including an input shaft configured to receive power from a driving portion, a gear unit connected to the input shaft to receive power from the driving portion through the input shaft, and an output shaft connected to the gear unit to output power from the driving portion through the input shaft. An output shaft is coupled to the gear unit and configured to transmit driving power, where the gear unit includes a spur gear coupled to the input shaft and a mounting gear disposed coaxially with the spur gear and coupled to the output shaft, and the spur gear is coupled to the mounting gear. The rotation angle of the output shaft is reduced by slight deformation of the gear unit.

Description

Technical Field

[0001] The present invention relates to a speed reducer and an independent steering system including the speed reducer, and more particularly to such a speed reducer and an independent steering system including the speed reducer, wherein the speed reducer is configured to achieve understeering characteristics by providing a structure that can undergo slight deformation even when no external force is applied. Background Art

[0002] Generally, the reducer is directly or indirectly connected to the motor, and is used to reduce the speed of the motor while amplifying the power, transmit the power to the gear train, and rotate the transmission shaft connected to the gear train, thereby moving the vehicle. There is a small vehicle reducer that uses a transmission belt or a transmission chain. However, a gear transmission reducer with high transmission efficiency and good durability is generally used, and helical gears are applied to reduce vibration and noise.

[0003] In the power transmission system of the speed reducer, the input shaft is splined and connected to the motor, and the gear is arranged on the outer diameter side of the input shaft and is engaged with the output gear. When power is transmitted to the output shaft, the gear arranged on the outer diameter side of the output shaft meshes with the drive gear of the differential device, so that power is transmitted to the differential device.

[0004] As described above, the speed reducer includes an input shaft, an output shaft, and a differential gear train, and includes a structure in which the first and second opposite ends of each shaft are supported on the speed reducer housing through bearings. The input shaft is directly connected and engaged to the motor through spline teeth, receives the power of the motor, and provides the output shaft as an intermediate connecting gear with a rotational force amplified by a gear ratio. The output gear provides the driving gear of the differential device with a rotational force amplified by a gear ratio.

[0005] Furthermore, recently, as a vehicle having a structure symmetrical in left / right and forward / rearward directions, a vehicle having a completely symmetrical shape has been developed, which is operated by an independent steering system connected to the vehicle. A completely symmetrical vehicle has a great advantage in providing a spacious space.

[0006] However, in the case of a completely symmetrical vehicle, during a steering maneuver, the neutral steering of the vehicle is performed relative to the center of gravity, which leads to the problem that a yaw motion of the vehicle continues to occur during the steering maneuver.

[0007] Therefore, it is necessary to apply compliance steering to a symmetrical vehicle in an effort to ensure a neutral steering drive tendency (which includes the same characteristics as a steering vehicle with an understeering tendency) by means of a configuration between internal gears that form an independent cornering module including a speed reducer.

[0008] The information included in this Background of the Invention section is only intended to enhance understanding of the overall background of the invention and should not be taken as an acknowledgment or any form of suggestion that this information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0009] Various aspects of the present invention are directed to providing a speed reducer configured to generate minute deformations between low-level components forming the speed reducer.

[0010] The present invention is directed to providing a structure for inducing minute deformation of a speed reducer by providing a structure for changing the shape of a spur gear and the shape of a mounting gear provided coaxially with the spur gear.

[0011] The purpose of the present invention is not limited to the above-mentioned purpose, and other purposes of the present invention not mentioned above can be understood from the following description and can be more clearly understood from the exemplary embodiments of the present invention. In addition, the purpose of the present invention can be achieved by the means defined in the claims and their combinations.

[0012] In order to achieve the above-mentioned object of the present invention, the speed reducer includes the following configuration.

[0013] In one aspect, the present invention provides a reducer comprising: an input shaft, a gear unit and an output shaft, wherein the input shaft is configured to receive power from a driving part; the gear unit is connected to the input shaft to receive power from the driving part through the input shaft; the output shaft is engaged to the gear unit and is configured to transmit driving power, wherein the gear unit comprises a spur gear and a mounting gear, the spur gear being engaged to the input shaft; the mounting gear is coaxially arranged with the spur gear and engaged to the output shaft.

[0014] In an exemplary embodiment, the spur gear may include at least two holes symmetrical with respect to a central axis connecting the spur gear and the mounting gear.

[0015] In another exemplary embodiment of the present invention, the reducer may further include: a rod portion and a stopper, wherein the rod portion is connected to the central axis of the mounting gear; and the stopper is arranged on the surface of the mounting gear so that the first relative end and the second relative end of the rod portion are connected to the stopper.

[0016] In yet another exemplary embodiment of the present invention, the mounting gear may include a bushing portion including an inner side fixed to a center shaft of the mounting gear and an outer side configured to abut against an inner peripheral surface of the mounting gear.

[0017] In yet another exemplary embodiment of the present invention, the bushing portion may be made of a high-hardness rubber material.

[0018] In still another exemplary embodiment of the present invention, the bushing portion may include one or more bushing holes disposed at equal intervals based on a central axis.

[0019] In a further exemplary embodiment of the present invention, the mounting gear may further include: a gasket hole, a rubber gasket and a shaft, wherein the gasket hole is formed in the mounting gear along two or more directions symmetrically relative to the central axis of the mounting gear; the rubber gasket is arranged in the gasket hole; the shaft is fixed to the central axis of the mounting gear and includes an extension portion corresponding to the gasket hole.

[0020] In another aspect, the present invention provides an independent steering system, comprising: an upper arm, a steering knuckle unit, a steering input part and a reducer, the upper arm comprising an end connected to a vehicle body; the steering knuckle unit is connected to the upper arm; the steering input part is configured to input a steering angle of the steering knuckle unit; the reducer is connected to the upper arm and is arranged between the steering input part and the steering knuckle unit; wherein the reducer comprises: an input shaft, a gear unit and an output shaft, the input shaft is configured to receive power from the steering input part; the gear unit comprises a spur gear engaged to the input shaft and a mounting gear coaxially arranged with the spur gear and engaged to the output shaft; the output shaft is engaged to the gear unit and is configured to transmit driving power.

[0021] In an exemplary embodiment of the present invention, the spur gear may include at least two holes symmetrical with respect to a central axis connecting the spur gear and the mounting gear.

[0022] In another exemplary embodiment of the present invention, the independent steering system may further include: a rod portion and a stopper, wherein the rod portion is connected to the central axis of the mounting gear; and the stopper is arranged on the surface of the mounting gear so that the first relative end and the second relative end of the rod portion are connected to the stopper.

[0023] In yet another exemplary embodiment of the present invention, the mounting gear may include a bushing portion including an inner side fixed to a center shaft of the mounting gear and an outer side configured to abut against an inner peripheral surface of the mounting gear.

[0024] In yet another exemplary embodiment of the present invention, the bushing portion may be made of a high-hardness rubber material.

[0025] In still another exemplary embodiment of the present invention, the bushing portion may include one or more bushing holes disposed at equal intervals based on a central axis.

[0026] In a further exemplary embodiment of the present invention, the mounting gear may further include: a gasket hole, a rubber gasket and a shaft, wherein the gasket hole is formed in the mounting gear along two or more directions symmetrically relative to the central axis of the mounting gear; the rubber gasket is arranged in the gasket hole; the shaft is fixed to the central axis of the mounting gear and includes an extension portion corresponding to the gasket hole.

[0027] In another further exemplary embodiment of the present invention, the shaft may include at least two extensions that are symmetrical with respect to a central axis on which the gear is mounted.

[0028] The present invention can obtain the following effects from the present embodiment described above and the configuration, joining, and use relationships to be described below.

[0029] The present invention provides an effect of arranging a speed reducer for changing the turning characteristics of a vehicle by minute deformation of the low-level structure of the speed reducer which generates lateral force.

[0030] In addition, the present invention produces a slight deformation by changing the shape of the spur gear and the shape of the mounting gear, thereby providing an independent steering system with understeering characteristics through the reducer, thereby achieving the effect of reducing costs.

[0031] Other aspects and exemplary embodiments of the invention are discussed below.

[0032] It should be understood that the term "vehicle" or "vehicular" or other similar terms used herein generally include motor vehicles, such as passenger vehicles including sport utility vehicles (SUVs), buses, trucks, various commercial vehicles, ships including various boats, marine vessels, aircraft, etc., and include hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles, and other alternative fuel vehicles (e.g., fuels derived from non-petroleum energy sources). As referred to herein, a hybrid vehicle is a vehicle having two or more sources of power, such as both gasoline-powered and electric-powered vehicles.

[0033] The above features and other features of the present invention are discussed below.

[0034] By incorporating the accompanying drawings and Figure 1 Other features and advantages of the methods and apparatus of the present invention will become more clearly apparent or elucidated with reference to specific embodiments which illustrate certain principles of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a schematic diagram exemplarily showing the configuration of a speed reducer provided to a steering system according to an exemplary embodiment of the present invention;

[0036] Figure 2A A schematic diagram of the configuration of a speed reducer according to an exemplary embodiment of the present invention in the case where driving power is applied to a steering input portion;

[0037] Figure 2B is a schematic diagram of the configuration of a gear unit according to an exemplary embodiment of the present invention;

[0038] Figure 3A is a schematic diagram exemplarily illustrating an engagement structure of a mounting gear including a rod portion according to an exemplary embodiment of the present invention;

[0039] Figure 3B A schematic diagram of a configuration of a mounting gear including a rod portion according to an exemplary embodiment of the present invention;

[0040] Figure 4A is a schematic diagram exemplarily illustrating an engagement structure of a mounting gear including a bushing portion according to another exemplary embodiment of the present invention;

[0041] Figure 4B A schematic diagram of a configuration of a mounting gear including a bushing portion according to another exemplary embodiment of the present invention;

[0042] Figure 5A Schematic diagram exemplarily showing an engagement structure of a mounting gear including a shaft according to various exemplary embodiments of the present invention;

[0043] Figure 5B A schematic diagram of a configuration of a mounting gear including a shaft according to various exemplary embodiments of the present invention; and

[0044] Figure 6 is a schematic diagram exemplarily illustrating an understeering motion of a symmetrical vehicle in a cornering environment according to an exemplary embodiment of the present invention.

[0045] It should be understood that the accompanying drawings are not necessarily drawn to scale, but rather show a slightly simplified depiction of various features that illustrate the basic principles of the invention. The intended design features of the present invention as included herein (including, for example, specific dimensions, orientations, locations, and shapes) will be determined in part by the specific target application and use environment.

[0046] In the figures, like reference numbers refer to the same or equivalent parts of the present invention throughout the several figures of the drawing. DETAILED DESCRIPTION

[0047] The following will be referred to in detail in various specific embodiments of the present invention, examples of which are presented in the accompanying drawings and described below. Although the present invention will be described in conjunction with exemplary embodiments of the present invention, it should be appreciated that this specification is not intended to limit the present invention to those exemplary embodiments of the present invention. On the other hand, the present invention is intended to cover not only the exemplary embodiments of the present invention, but also various alternative forms, modified forms, equivalent forms and other embodiments that may be included in the spirit and scope of the present invention as defined by the appended claims.

[0048] Various embodiments of the present invention will now be cited in detail, examples of which are shown in the accompanying drawings and described below. Although the present invention will be described in conjunction with exemplary embodiments of the present invention, it should be appreciated that this specification is not intended to limit the present invention to those exemplary embodiments of the present invention. On the other hand, the present invention is intended to cover not only the exemplary embodiments of the present invention, but also various alternative forms, modified forms, equivalent forms and other embodiments that may be included within the spirit and scope of the present invention as defined by the appended claims.

[0049] Hereinafter, various exemplary embodiments of the present invention will be described in more detail with reference to the accompanying drawings. The exemplary embodiments of the present invention may be modified in various different forms, and it should not be understood that the scope of the present invention is limited to the following embodiments. These exemplary embodiments are provided to explain the present invention more completely to those skilled in the art.

[0050] In addition, the terms "unit", "component", "module", etc. described in the specification refer to units configured to perform at least one function or operation, and the "unit" and "component" etc. can be implemented by hardware, software, or a combination of hardware and software.

[0051] In addition, the terms used in this specification are only used to describe various exemplary embodiments and are not intended to limit the embodiments. A singular expression includes a plural expression unless it is clearly mentioned as a different meaning in the context.

[0052] Furthermore, in the present specification, the names of constituent elements are classified as first . . . , second . . . , etc. to distinguish constituent elements including the same name, and the names are not substantially limited to the order in the following description.

[0053] Hereinafter, exemplary embodiments will be described in detail with reference to the accompanying drawings. In the description of the exemplary embodiments with reference to the accompanying drawings, the same or corresponding constituent elements are given the same reference numerals regardless of the figure numbers, and repeated descriptions thereof will be omitted.

[0054] The present invention relates to a speed reducer 40. The present invention relates to a speed reducer 40 and an independent steering system including the speed reducer 40.

[0055] In addition, the independent steering system of the present invention is a single steering system coupled to each wheel. In the case of a multi-wheel vehicle, an independent steering system configured to independently perform steering motions may be provided to each vehicle wheel. In addition, in an exemplary embodiment of the present invention, a vehicle equipped with an independent steering system includes a vehicle symmetrical in the forward / rearward direction and the left / right direction, and the vehicle refers to a vehicle having a neutral steering characteristic corresponding to a steering angle input in a state where the reducer is not slightly deformed.

[0056] Hereinafter, exemplary embodiments will be described in detail with reference to the accompanying drawings. In the detailed description with reference to the accompanying drawings, the same or corresponding constituent elements are given the same reference numerals regardless of the figure numbers, and their repeated description will be omitted.

[0057] The present invention relates to an independent steering system configured so that a steering knuckle unit 50 coupled to a wheel can be independently rotated.

[0058] In addition, the independent steering system of the present invention includes a structure that can be connected to each wheel and independently perform steering movements. The vehicle wheels equipped with the independent steering system can be configured so that the outer wheels include a steering angle of 60 degrees and the inner wheels include a steering angle of 90 degrees.

[0059] Figure 1 is a perspective view of an independent steering system including a speed reducer 40 according to an exemplary embodiment of the present invention.

[0060] The independent steering system of the present invention includes a lower arm 20 and an upper arm 10 arranged in the width direction of the vehicle. The independent steering system includes a knuckle unit 50, which is arranged between the lower arm 20 and the upper arm 10 and includes an outer surface to which a wheel is connected. The upper arm 10 includes a structure connected to the upper end of the knuckle unit 50, extending downward in the height direction, and connected to the lower arm 20. The speed reducer 40 is arranged at the upper end of the upper arm 10, and transmits the driving power to the knuckle unit 50 when the driving power is applied from the steering input part 30. The upper arm 10 connected to the output shaft 42 of the speed reducer 40 rotates integrally with the knuckle unit 50, and rotates around the speed reducer 40 integrally with the output shaft 42.

[0061] In an exemplary embodiment of the present invention, the steering knuckle unit 50 is configured to be fixed to the upper arm 10, and the upper arm 10 is configured to be connected to the output shaft 42 of the reducer 40, so that the steering knuckle unit 50 can rotate integrally with the upper arm 10 around the output shaft 42 as the center axis in the forward / rearward direction of the vehicle.

[0062] In addition, the independent steering system includes a steering input portion 30, which is fixed to the vehicle body and configured to be connected to the upper end of the upper arm 10, so as to apply a steering force in response to a user's steering input. In an exemplary embodiment of the present invention, the steering input portion 30 may be configured as a steering motor configured to receive an electronic signal and change a steering angle of the steering knuckle unit 50. The steering input portion 30 may be provided at the upper end of the upper arm 10 and connected to the upper arm 10 through a speed reducer 40.

[0063] The lower arm 20 is provided at the lower end of the upper arm 10 and is fastened to the lower end of the knuckle unit 50. One end of the lower arm 20 and the lower end of the knuckle unit 50 are coupled by a fastening unit. The fastening unit is configured to absorb forward and backward movement and left and right movement applied from the wheel.

[0064] The fastening unit is disposed adjacent to the lower end of the knuckle unit 50. In an exemplary embodiment of the present invention, a ball stud of the fastening unit may be inserted into the knuckle unit 50, and a clamping bolt or a locking nut may be provided to integrally fix the knuckle unit 50 and the ball stud.

[0065] The independent steering system includes a speed reducer 40 disposed between the upper arm 10 and the steering input portion 30 and configured to be connected to the upper end portion of the upper arm 10. An input shaft 41 of the speed reducer 40 is connected to a driving shaft of the steering input portion 30, and an output shaft 42 connected to the upper arm 10 is configured to apply a rotational force to the upper arm 10.

[0066] Figure 2A The speed reducer 40 connected to the upper arm 10 is shown, and the motor as a component of the steering input portion 30 is shown, Figure 2B FIG. 4 is a schematic diagram showing the structure of the reducer 40 for example.

[0067] The speed reducer 40 is disposed on the upper surface of the upper arm 10, and the input shaft 41 of the speed reducer 40 is configured as a driving shaft of the steering motor of the steering input portion 30. In an exemplary embodiment of the present invention, the upper arm 10 is disposed at the upper end of the steering knuckle unit 50 connected to the wheel, and the upper arm 10 and the steering knuckle unit 50 are configured to rotate integrally. The upper arm 10 may be disposed adjacent to the lower surface of the speed reducer 40, and the upper arm 10 may be configured to rotate integrally with the output shaft 42 in response to the rotational force of the output shaft 42 of the speed reducer 40. That is, the upper arm 10 connected to the output shaft 42 of the speed reducer 40 may be configured so that the steering knuckle unit 50 and the upper arm 10 rotate integrally around the output shaft 42 of the speed reducer 40.

[0068] The speed reducer 40 includes an input shaft 41 configured as a driving shaft of a motor and a gear unit 100 connected to receive the rotational force of the input shaft 41. The speed reducer 40 includes an output shaft 42 connected to the gear unit 100 to transmit driving power so that the upper arm 10 and the knuckle unit 50 rotate integrally.

[0069] The gear unit 100 includes a spur gear 110, which is gear-engaged to a gear 41a provided on the input shaft 41, and a mounting gear 120, which is coaxially provided with the spur gear 110 and is engaged to the output shaft 42. Therefore, the driving power of the steering input portion 30 is input through the input shaft 41. When the gear 41a of the input shaft 41 rotates, the gear unit 100 transmits the driving power to the output shaft 42 in conjunction with the rotation of the gear 41a.

[0070] The gear unit 100 is configured to apply power applied through the input shaft 41 to the output shaft 42. The gear unit 100 is configured to be slightly deformed as power is applied. That is, in an exemplary embodiment of the present invention, at least one of the spur gear 110 and the mounting gear 120 is slightly deformed, and the rotation angle of the output shaft 42 output in response to the power applied through the input shaft 41 is relatively reduced compared to the normal rotation angle of the output shaft 42 when power is applied to the input shaft 41 without slight deformation.

[0071] In a state where the spur gear 110 is gear-engaged to the gear 41a of the input shaft 41, the spur gear 110 rotates inwardly in the height direction of the speed reducer 40. In addition, the independent steering system includes a mounting gear 120 that is coaxially disposed with the spur gear 110 and gear-engaged to the gear 42a of the output shaft 42. In this case, the gear 41a disposed on the input shaft 41 and the gear 42a disposed on the output shaft 42 may be integrated with the input shaft 41 or / and the output shaft 42, respectively.

[0072] The spur gear 110 is coaxially disposed with the mounting gear 120 and is disposed at one end portion of the opposite lower end portion of the mounting gear 120. The spur gear 110 may be disposed in the height direction of the center shaft 113 while corresponding to the position of the gear 41a of the input shaft 41. The spur gear 110 includes at least two holes 111 configured to be symmetrical with each other with respect to the center shaft 113. In an exemplary embodiment of the present invention, the independent steering system of the present invention includes the holes 111 radially formed to include an angle of 90 degrees with respect to each other based on the center shaft 113.

[0073] Figure 3A and Figure 3B FIG. 1 is a schematic diagram exemplarily showing a configuration of a mounting gear 120 including a rod portion 130 according to an exemplary embodiment of the present invention.

[0074] As shown in the figure, the gear unit 100 includes a spur gear 110 provided at a position corresponding to the gear 41a of the input shaft 41, and a mounting gear 120 gear-engaged with the gear 42a of the output shaft 42. The mounting gear 120 is provided inside the speed reducer 40, and is configured to rotate around the central axis 113. The rod portion 130 is provided at a position facing one surface of the mounting gear 120, and extends symmetrically to opposite sides with respect to the central axis 113. The rod portion 130 extends the same length from the central axis 113 toward opposite sides, and is provided to abut against one side surface of the mounting gear 120.

[0075] In addition, a stopper 121 is provided on one side surface of the mounting gear 120, and two opposite ends of the rod portion 130 are positioned at the stopper 121. The stopper 121 is configured to surround two opposite surfaces of the end of the rod portion 130, and the stopper 121 protrudes from one side surface of the mounting gear 120. In addition, the stopper includes two protruding portions, which are provided adjacent to the side surface of the end of the rod portion 130 to surround the two opposite surfaces of the rod portion 130. That is, the stopper 121 provided at one end of the rod portion 130 includes two protruding portions provided to abut against the two opposite surfaces of the end of the rod portion 130. In addition, the stopper 121 provided at the other end of the rod portion 130 also includes two protruding portions configured to fix the rod portion 130 while abutting against the two opposite surfaces.

[0076] Furthermore, in an exemplary embodiment of the present invention, the rod portion 130 provided on the central shaft 113 may be fixedly inserted into the central shaft 113. While the outer surface of the gear 120 is abutted against the central portion, the rod portion 130 is provided in the form of a bidirectionally extending cantilever beam.

[0077] Figure 4A and Figure 4B A bushing portion 140 provided on the central shaft 113 of the mounting gear 120 according to another exemplary embodiment of the present invention is illustrated.

[0078] The bushing portion 140 is located outside the central axis 113 of the mounting gear 120 and abuts against the inner circumferential surface of the mounting gear 120. The bushing portion 140 radially extends from the central axis 113 and includes at least one bushing hole 141 formed in the extending direction of the bushing portion 140.

[0079] In addition, the bushing portion 140 may be made of a rubber material having high hardness. The polymer elastomer may be selected from various types of thermoplastic materials having relatively high hardness, such as polyurethane rubber or polyester rubber, and the thermosetting material may be a combination of natural rubber or various types of synthetic rubber.

[0080] The mounting gear 120 including the bushing portion 140 has a relatively smaller rotation angle according to the rotation of the input shaft 41 compared to the mounting gear 120 not including the bushing portion 140 .

[0081] Therefore, the mounting gear 120 including the bushing portion 140 is slightly deformed. Therefore, the rotation angle of the output shaft 42 is relatively smaller than that of the output shaft 42 of the speed reducer not including the bushing portion 140.

[0082] As described above, in another exemplary embodiment of the present invention, minute deformation is performed by the bushing portion 140 provided on the central shaft 113 of the mounting gear 120 and the bushing hole 141 provided on the bushing portion 140. Therefore, even when the same power is applied through the input shaft 41, the rotation amount of the output shaft 42 is reduced.

[0083] Figure 5A and Figure 5B A configuration of a mounting gear 120 including a rubber pad 160 according to another exemplary embodiment of the present invention is shown.

[0084] The mounting gear 120 geared with the output shaft 42 may include a shaft 170 disposed on the central axis 113 of the mounting gear 120. The shaft 170 is inserted into the central axis 113 and extends symmetrically and bidirectionally from the central axis 113. In an exemplary embodiment of the present invention, the shaft 170 includes at least two or more extensions. In an exemplary embodiment of the present invention, the shaft 170 of the present invention may include four extensions disposed at an angle of 90 degrees relative to each other, and the shaft 170 is configured to be accommodated in a gasket hole 150 formed in the mounting gear 120.

[0085] In addition, the packing hole 150 formed in the mounting gear 120 includes a rubber packing 160 disposed between the shaft 170 and the packing hole 150. Therefore, in a case where the spur gear 110 is rotated by the driving power of the input shaft 41, the mounting gear 120 disposed coaxially with the spur gear 110 is integrally rotated with the central axis 113 of the spur gear 110, so that the rubber packing 160 disposed inside the packing hole 150 is deformed according to the rotation of the shaft 170.

[0086] As described above, the rubber gasket 160 is slightly deformed according to the rotation of the shaft 170 of the mounting gear 120 including the rubber gasket 160, so that the rotation amount of the mounting gear 120 is relatively reduced. The rotation angle of the output shaft 42 is reduced according to the slight deformation.

[0087] That is, the speed reducer 40 according to the exemplary embodiment of the present invention including the shaft 170 and the rubber pad 160 may be slightly deformed. In the case of an independent steering system including the speed reducer 40, a steering motion of a vehicle may be applied according to an understeering characteristic of a steering angle input.

[0088] Figure 6 A steering environment is shown which is changed to an understeering characteristic of a vehicle including a neutral steering characteristic in the case of using a speed reducer which applies a small deformation to an independent steering module located at a front end portion of a vehicle according to an exemplary embodiment of the present invention.

[0089] In an exemplary embodiment of the present invention, the vehicle is a symmetrical vehicle in the left / right direction and the forward / rearward direction and is configured so that the center of gravity is located at the central portion of the vehicle. The vehicle includes a neutral steering characteristic without applying a slight deformation of the gear unit 100 of the present invention.

[0090] However, in the case where a slight deformation of the gear unit 100 is applied by the speed reducer of the present invention, follow-up steering occurs in response to the steering input. Therefore, the steering operation is performed so that the vehicle includes understeering characteristics.

[0091] In an exemplary embodiment of the present invention, the gear unit 100 forming a speed reducer of an independent steering system located at a front end of a vehicle may include a mounting gear including at least one of a rod portion 130, a bushing portion 140, and a rubber pad 160. Optionally, the gear unit 100 may include a spur gear 110 having a plurality of holes 111. Therefore, the speed reducer located at the front end of the vehicle causes a slight deformation of the gear unit 100 in response to the power applied to the input shaft 41. Therefore, the steering angle output is performed so that the rotation angle of the output shaft 42 is relatively reduced.

[0092] The foregoing detailed description illustrates the present invention. In addition, the foregoing description only shows and describes exemplary embodiments of the present invention, and the present invention can be used in various other combinations, modifications and environments. That is, changes or modifications can be made within the scope of the concept of the present invention included in this specification, within the scope equivalent to the disclosed scope and / or within the scope of the technology or knowledge in the art. The disclosed exemplary embodiments are provided to explain the best state for implementing the technical spirit of the present invention, and various modifications required for the intended application field and the use of the present invention can be made. Therefore, the detailed description of the present invention is not intended to limit the present invention to the disclosed exemplary embodiments of the present invention. In addition, the attached claims should be interpreted as including other embodiments.

[0093] For convenience of explanation and precise definition of the appended claims, the terms "upper", "lower", "inner", "outer", "above", "below", "upward", "downward", "front", "rear", "back", "inside", "outside", "inwardly", "outwardly", "interior", "exterior", "inner", "exterior", "forward", "rearward" are used to describe the features of the exemplary embodiments with reference to the positions of such features as shown in the accompanying drawings. It will be further understood that the term "connect" or its derivatives refer to both direct and indirect connections.

[0094] The term "and / or" may include a combination of a plurality of related listed items or any one of a plurality of related listed items. For example, "A and / or B" includes all three cases, such as "A", "B" and "A and B".

[0095] In this specification, unless otherwise stated, a singular expression includes a plural expression unless the context clearly indicates otherwise.

[0096] In an exemplary embodiment of the present invention, “at least one of A and B” may refer to “at least one of A or B” or “at least one of a combination of at least one of A and B”. Furthermore, “one or more of A and B” may refer to “one or more of A or B” or “one or more of a combination of one or more of A and B”.

[0097] In exemplary embodiments of the present invention, it should be understood that terms such as “including” or “having” are intended to specify the presence of features, values, steps, operations, elements, parts, or a combination thereof described in the specification, and do not exclude the possibility of adding or existing one or more other features, values, steps, operations, elements, parts, or a combination thereof.

[0098] The foregoing description of the specific exemplary embodiments of the present invention is presented for the purpose of illustration and description. The foregoing description is not intended to be exhaustive, nor is it intended to limit the present invention to the precise form disclosed, and it is apparent that many changes and variations are possible in light of the above teachings. The exemplary embodiments are selected and described in order to explain the specific principles of the present invention and its practical application, so that other technicians in the field can realize and utilize the various exemplary embodiments of the present invention and its different selected forms and modified forms. The scope of the present invention is intended to be limited by the appended claims and their equivalents.

Claims

1. A reducer, comprising: an input shaft configured to receive power from the drive portion; a gear unit connected to the input shaft to receive power from the driving portion through the input shaft; as well as an output shaft coupled to the gear unit and configured to transmit driving power; Wherein, the gear unit comprises: a spur gear engaged to the input shaft; and a mounting gear coaxially disposed with the spur gear and engaged to the output shaft; Therein, the rotation angle of the output shaft is reduced by a slight deformation of the gear unit.

2. The reducer according to claim 1, wherein: The spur gear includes at least two holes symmetrical with respect to a central axis connecting the spur gear and the mounting gear.

3. The reducer according to claim 1, further comprising: a rod portion connected to a central shaft of the mounting gear, wherein the central shaft connects the spur gear and the mounting gear; and A stopper is provided on a surface of the mounting gear such that the first opposite end portion and the second opposite end portion of the rod portion are connected to the stopper.

4. The reducer according to claim 3, wherein: The rod portion extends from a central axis of the mounting gear in a radial direction of the mounting gear.

5. The reducer according to claim 1, further comprising: A bushing portion includes an inner side fixed to a center shaft of a mounting gear connecting the spur gear and the mounting gear and an outer side configured to abut against an inner peripheral surface of the mounting gear.

6. The reducer according to claim 5, wherein: The bushing part is made of high-hardness rubber material.

7. The reducer according to claim 5, wherein: The bushing portion includes one or more bushing holes arranged at equal intervals based on a central axis.

8. The reducer according to claim 1, wherein: The mounting gear further comprises: a gasket hole formed in the mounting gear in two or more directions symmetrically with respect to a central axis of the mounting gear, wherein the central axis connects the spur gear and the mounting gear; a rubber gasket disposed in the gasket hole; and A shaft is fixed to the central shaft of the mounting gear and includes an extension portion corresponding to the gasket hole.

9. The reducer according to claim 8, wherein: The gasket hole extends from a central axis of the mounting gear in a radial direction of the mounting gear.

10. An independent steering system comprising: an upper arm including an end connected to the vehicle body; a steering knuckle unit connected to the upper arm; a steering input portion configured to input a steering angle of the steering knuckle unit; as well as a speed reducer connected to the upper arm and disposed between the steering input portion and the knuckle unit; Wherein, the reducer comprises: an input shaft configured to receive power from the steering input portion; a gear unit comprising a spur gear coupled to the input shaft and a mounting gear disposed coaxially with the spur gear and coupled to the output shaft; and an output shaft configured to transmit driving power; Therein, the rotation angle of the output shaft is reduced by a slight deformation of the gear unit.

11. The independent steering system according to claim 10, wherein: The spur gear includes at least two holes symmetrical with respect to a central axis connecting the spur gear and the mounting gear.

12. The independent steering system of claim 10, further comprising: a rod portion connected to a central shaft of the mounting gear, wherein the central shaft connects the spur gear and the mounting gear; and A stopper is provided on a surface of the mounting gear such that the first and second opposite ends of the rod portion are connected to the stopper.

13. The independent steering system according to claim 12, wherein: The rod portion extends from a central axis of the mounting gear in a radial direction of the mounting gear.

14. The independent steering system of claim 10, further comprising: A bushing portion includes an inner side fixed to a center shaft of a mounting gear and an outer side configured to abut against an inner peripheral surface of the mounting gear, wherein the center shaft connects the spur gear and the mounting gear.

15. The independent steering system of claim 14, wherein: The bushing part is made of high-hardness rubber material.

16. The independent steering system of claim 14, wherein: The bushing portion includes one or more bushing holes arranged at equal intervals based on a central axis.

17. The independent steering system of claim 10, wherein: The mounting gear further comprises: a gasket hole formed in the mounting gear in two or more directions symmetrically with respect to a central axis of the mounting gear, wherein the central axis connects the spur gear and the mounting gear; a rubber gasket disposed in the gasket hole; and A shaft is fixed to the central shaft of the mounting gear and includes an extension portion corresponding to the gasket hole.

18. The independent steering system of claim 17, wherein: The gasket hole extends from a central axis of the mounting gear in a radial direction of the mounting gear.

19. The independent steering system of claim 17, wherein: The shaft includes at least two extensions that are symmetrical with respect to a central axis on which the gear is mounted.

Images