SUSPENSION FOR A VEHICLE

Abstract

A suspension for a vehicle provides a configuration in which a bolt is screw-fastened to a stud part of a ball joint in a state in which the stud part is inserted into a knuckle, an outer diameter of the stud part is increased at the time of fastening the bolt so that the stud part and the knuckle are coupled to each other. Thus, a position of a hard point corresponding to a center of the ball joint is not changed when the ball joint is coupled by the bolt.

Claims

1. A suspension for a vehicle, the suspension comprising: a lower arm and a knuckle disposed to be spaced apart from each other; a ball joint including: a first end having a ball part and coupled to the lower arm, and a second end corresponding to a stud part and installed by being inserted into the knuckle; and a bolt fastened to the stud part by penetrating the knuckle in a direction opposite to a direction in which the stud part is inserted, the bolt configured to enter the stud part in a longitudinal direction of the stud part.

2. The suspension of claim 1, wherein the stud part is spread outward and expanded in outer diameter when the bolt is fastened to the stud part, and wherein a restrictive force is implemented as a contact between the stud part and the knuckle increases when the outer diameter is expanded, such that the stud part and the knuckle are coupled.

3. The suspension of claim 1, wherein a screw groove is formed at a center of the stud part and extends in the longitudinal direction of the stud part, and the screw groove is screw-fastened to a threaded portion of the bolt.

4. The suspension of claim 1, wherein the knuckle includes: a stud part insertion groove into which the stud part of the ball joint is inserted, a head part insertion groove into which a head part of the bolt is inserted and seated, and an intermediate hole configured to connect the stud part insertion groove and the head part insertion groove, and wherein the stud part insertion groove, the head part insertion groove, and the intermediate hole are connected to each other on a same axis.

5. The suspension of claim 4, wherein the stud part is split into a plurality of stud portions by two or more cut-out grooves cut in the longitudinal direction of the stud part.

6. The suspension of claim 5, wherein a protrusion portion protrudes inward from an inner diameter of the stud part insertion groove, wherein the protrusion portion is inserted into the cut-out groove when the stud part is inserted into the stud part insertion groove, and wherein the protrusion portion inserted into the cut-out groove prevents a rotation of the ball joint when the bolt is fastened or unfastened.

7. The suspension of claim 5, wherein the head part insertion groove has a tapered surface having a diameter that gradually increases toward the other side of the head part insertion groove opposite to an inner side connected to the intermediate hole, and wherein the head part of the bolt has a tapered shape corresponding to the tapered surface of the head part insertion groove, such that the head part insertion groove and the head part of the bolt are in surface contact with each other.

8. The suspension of claim 3, wherein a diameter of the screw groove of the stud part is smaller than a diameter of the threaded portion of the bolt before the bolt is fastened to the stud part, and wherein an outer diameter of the stud part is expanded, and the stud part is coupled to the knuckle when the threaded portion of the bolt is inserted and fastened into the screw groove of the stud part.

9. The suspension of claim 4, wherein even though an axial force is applied in an axial direction to the ball joint when the bolt is fastened to the stud part in a state in which the stud part is inserted into the stud part insertion groove, a state in which the stud part is supported in the stud part insertion groove is maintained such that the ball joint does not move in the axial direction, and wherein a position of a hard point of the ball joint is not changed as the ball joint does not move in the axial direction at a time of fastening the bolt.

10. The suspension of claim 6, wherein when the ball joint and the knuckle are completely coupled by fastening the bolt, an axial movement and radial movement of the ball joint are restricted by a screw fastening force between the bolt and the stud part and a coupling force implemented by contact between the stud part and the knuckle, and a restriction made by the cut-out groove and the protrusion portion prevents a circumferential rotation.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] FIG. 1 is a view for explaining a state in which a ball joint for connecting a knuckle and a lower arm is coupled to the knuckle by a bolt according to an embodiment of the present disclosure.

[0032] FIG. 2 is a view for explaining a protrusion portion formed on the knuckle according to an embodiment of the present disclosure.

[0033] FIG. 3 is a view for explaining a state in which a stud part is split into a plurality of stud portions by cut-out grooves according to an embodiment of the present disclosure.

[0034] FIGS. 4 to 5 are views illustrating a state in which the bolt is not fastened to the stud part and a state in which the bolt is fastened to the stud part according to an embodiment of the present disclosure.

DETAILED DESCRIPTION

[0035] Hereinafter, embodiments disclosed in the present specification are described in detail with reference to the accompanying drawings. The same or similar constituent elements are assigned with the same reference numerals regardless of reference numerals, and the repetitive description thereof is omitted.

[0036] The suffixes module, unit, part, and portion used to describe constituent elements in the following description are used together or interchangeably in order to facilitate the description, but the suffixes themselves do not have distinguishable meanings or functions.

[0037] In the description of the embodiments of the present disclosure, the specific descriptions of publicly known related technologies are omitted when it is determined that the specific descriptions may obscure the subject matter of the embodiments disclosed in the present specification.

[0038] In addition, it should be understood that the accompanying drawings are provided only to allow those having ordinary skill in the art to easily understand the embodiments disclosed in the present specification, and the technical spirit disclosed in the present specification is not limited by the accompanying drawings, and includes all alterations, equivalents, and alternatives that are included in the spirit and the technical scope of the present disclosure.

[0039] The terms including ordinal numbers such as first, second, and the like may be used to describe various constituent elements, but the constituent elements are not limited by the terms. These terms are used only to distinguish one constituent element from another constituent element.

[0040] When one constituent element is described as being coupled or connected to another constituent element, it should be understood that one constituent element can be coupled or connected directly to another constituent element, and an intervening constituent element can also be present between the constituent elements.

[0041] When one constituent element is described as being coupled directly to or connected directly to another constituent element, it should be understood that no intervening constituent element is present between the constituent elements.

[0042] Singular expressions include plural expressions unless clearly described as different meanings in the context.

[0043] In the present specification, it should be understood the terms comprises, comprising, includes, including, containing, has, having or other variations thereof are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, components, or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

[0044] In addition, the term control unit or unit including motor control unit (MCU) or hybrid control unit (HCU) is merely a term widely used to name a control device (controller or control unit) for controlling a particular vehicle function but does not mean a generic function unit.

[0045] The control unit (controller) may include a communication device configured to communicate with another control unit or a sensor to control a corresponding function, a memory configured to store an operating system, a logic command, and input/output information, and one or more processors configured to perform determination, computation, decision, or the like required to control the corresponding function.

[0046] When a component, device, element, or the like of the present disclosure is described as having a purpose or performing an operation, function, or the like, the component, device, or element should be considered herein as being configured to meet that purpose or to perform that operation or function.

[0047] Hereinafter, a suspension for a vehicle according to an embodiment of the present disclosure is described with reference to the accompanying drawings.

[0048] As illustrated in FIGS. 1 to 5, the suspension for a vehicle includes: a lower arm 100 corresponding to a suspension arm for controlling a motion of a wheel of the vehicle, a knuckle 200 or carrier of the vehicle wheel, a ball joint 300 installed to connect the lower arm 100 and the knuckle 200, and a bolt 400 configured to couple the knuckle 200 and the ball joint 300.

[0049] Based on the state illustrated in the drawings, the lower arm 100 is positioned below the knuckle 200, and the lower arm 100 and the knuckle 200 are disposed to be spaced apart from each other in an upward/downward direction.

[0050] The ball joint 300 is disposed to extend in an upward and downward direction corresponding to a longitudinal direction of an axis. The ball joint 300 is installed to connect the knuckle 200 and the ball joint 300 by a fastening force of the bolt 400.

[0051] The knuckle 200 has a hole formed through upper and lower surfaces of the knuckle 200. The hole is formed by a stud part insertion groove 210, a head part insertion groove 220, and an intermediate hole 230. In particular, the stud part insertion groove 210, the head part insertion groove 220, and the intermediate hole 230 are connected to each other.

[0052] The stud part insertion groove 210 is opened from a bottom surface of the knuckle 200. A stud part 320 of the ball joint 300 is inserted into the stud part insertion groove 210.

[0053] The head part insertion groove 220 is opened from a top surface of the knuckle 200. A head part 410 of the bolt 400 is inserted into the head part insertion groove 220.

[0054] The intermediate hole 230 is disposed between the stud part insertion groove 210 and the head part insertion groove 220 and connects the stud part insertion groove 210 and the head part insertion groove 220.

[0055] The stud part insertion groove 210, the head part insertion groove 220, and the intermediate hole 230 are connected straight on the same axis.

[0056] The ball joint 300 includes a ball part 310 having a spherical shape, the stud part 320 protruding from the ball part 310, a ball cap 330 configured to surround the ball part 310, a bearing 340 installed between the ball part 310 and the ball cap 330, a ball casing 350 configured to cover an outer side of the ball cap 330, and a dust cover 360 configured to seal an opened upper side of the ball casing 350.

[0057] One end (a lower end) of the ball joint 300, at which the ball part 310 is provided, is fixedly coupled to the lower arm 100, and the other end (an upper end) of the ball joint 300, which corresponds to the stud part 320, is installed to be inserted into the stud insertion groove 210 of the knuckle 200.

[0058] The bolt 400 is installed as the bolt 400 penetrates the knuckle 200 in a direction opposite to a direction in which the stud part 320 is inserted, the bolt 400 enters the stud part 320 in a longitudinal direction of the stud part 320, and the bolt 400 is screw-fastened to the stud part 320.

[0059] In other words, a threaded portion 420 of the bolt 400 penetrates the head part insertion groove 220 and the intermediate hole 230 of the knuckle 200 and then is screw-fastened to the stud part 320 of the ball joint 300 in a state where the stud part 320 is being inserted into the stud insertion groove 210.

[0060] A screw groove 370 is formed at a center of the stud part 320 of the ball joint 300 and extends in the longitudinal direction of the stud part 320. The screw groove 370 is screw-fastened to the threaded portion 420 of the bolt 400.

[0061] Two or more cut-out grooves 380 are formed in the stud part 320 of the ball joint 300 by being cut in the longitudinal direction of the stud part 320, and the stud part 320 is split into a plurality of stud portions 320 by the cut-out grooves 380.

[0062] Therefore, when the threaded portion 420 of the bolt 400 penetrates the head part insertion groove 220 and the intermediate hole 230 of the knuckle 200 and then is fastened by being inserted into the screw groove 370 of the stud part 320, the plurality of stud portions 320 separated by the cut-out grooves 380 is spread outward and expanded in outer diameter. When the outer diameter of the plurality of stud portions 320 is expanded, a contact area between the stud part 320 and the stud insertion groove 210 of the knuckle 200 increases, and a restrictive force is implemented, such that the stud part 320 of the ball joint 300 is coupled to the knuckle 200.

[0063] Further, one or more protrusion portions 240 protrude inward from an inner diameter of the stud part insertion groove 210 of the knuckle 200. The protrusion portion 240 is inserted into the cut-out groove 380 of the stud part 320 when the stud part 320 of the ball joint 300 is inserted into the stud part insertion groove 210.

[0064] Therefore, the protrusion portion 240 inserted into the cut-out groove 380 may prevent a rotation of the ball joint 300 when the bolt 400 is fastened or unfastened, thereby maintain a more robust fastening force.

[0065] The head part insertion groove 220 of the knuckle 200 has a tapered surface having a diameter that gradually increases toward the other side (upward) of the head part insertion groove 220 that is opposite to an inner side connected to the intermediate hole 230. A bottom surface of the head part 410 of the bolt 400 has a tapered shape corresponding to the tapered surface of the head part insertion groove 220, such that the head part insertion groove 220 and the head part 410 of the bolt 400 are in surface contact with each other. Therefore, a clearance between the head part insertion groove 220 and the head part 410 may be removed, which makes it possible to maintain a more robust fastening force.

[0066] The threaded portion 420 of the bolt 400 is inserted and fastened into the screw groove 370 of the stud part 320 of the ball joint 300. When the threaded portion 420 is inserted into the screw groove 370, the plurality of stud portions 320 separated by the cut-out grooves 380 is spread outward and expanded in outer diameter. When the outer diameter of the plurality of stud portions 320 is expanded, a contact area between the stud part 320 and the stud insertion groove 210 of the knuckle 200 increases, and a restrictive force is implemented, such that the stud part 320 of the ball joint 300 is coupled to the knuckle 200.

[0067] To this end, before the threaded portion 420 of the bolt 400 is fastened to the screw groove 370 of the stud part 320, a diameter D1 of the screw groove 370 of the stud part 320 may be smaller than a diameter D2 of the threaded portion 420 of the bolt 400.

[0068] According to the suspension for a vehicle according to the present disclosure described above, the axial force is applied in the axial direction to the ball joint 300 when the threaded portion 420 of the bolt 400 is fastened to the screw groove 370 of the stud part 320 in the state in which the stud part 320 of the ball joint 300 is inserted into the stud part insertion groove 210 of the knuckle 200. Even though the axial force is applied, the state in which the stud part 320 is supported in the stud part insertion groove 210 is maintained, such that the ball joint 300 does not move in the axial direction.

[0069] When the ball joint 300 does not move in the axial direction at the time of fastening the bolt 400, the position of the hard point corresponding to the center of the ball joint 300 is not changed. Because the position of the hard point of the ball joint 300 is not changed, the geometrical characteristics of the vehicle are not changed, such that the suspension of the vehicle may sufficiently perform the inherent function.

[0070] In the embodiments according to the present disclosure, because the ball joint 300 does not move in the axial direction at the time of fastening the bolt 400, the stud part 320 made of a steel material does not penetrate into the knuckle 200 made of an aluminum material. Therefore, unlike the structure in the related art, the knuckle 200 is not damaged and it is not necessary to provide an insert component, such as a pipe bushing, in the knuckle 200 to prevent a damage caused when the stud part penetrates the knuckle. Therefore, it is possible to reduce the number of components, weight, and costs.

[0071] In addition, in the embodiment according to the present disclosure, because the threaded portion 420 of the bolt 400 is inserted and fastened into the screw groove 370 in the longitudinal direction of the stud part 320, it is not necessary to separately provide the fastening space of the bolt 400, which implements an advantage in terms of a layout. In particular, unlike the structure in the related art, a nut and a nut-related component are not used, which may simplify the configuration and reduce the weight and costs.

[0072] In addition, in the embodiment according to the present disclosure, because the bolt 400 is inserted into the stud part 320 in the longitudinal direction and screw-fastened to the stud part 320, an overall length of the ball joint 300 may be reduced, and the position of the hard point corresponding to the center of the ball joint 300 may be close to the ground surface as the length of the ball joint 300 is reduced, thereby configuring a geometry advantageous in terms of lateral rigidity of the vehicle.

[0073] In the embodiment according to the present disclosure, when the ball joint 300 and the knuckle 200 are completely coupled by fastening the bolt 400, the axial movement and radial movement of the ball joint 300 are restricted by a screw fastening force between the bolt 400 and the stud part 320 and a coupling force implemented by contact between the stud part 320 and the knuckle 200, and the restriction made by the cut-out grooves 380 and the protrusion portion 240 prevents the circumferential rotation, which makes it possible to maintain a more robust coupled state.

[0074] While the specific embodiments of the present disclosure have been illustrated and described, it should be obvious to those having ordinary skill in the art that the present disclosure may be variously modified and changed without departing from the technical spirit of the present disclosure.