Bumper rubber insert for a vibration damper

Abstract

Bumper rubber insert (100) for a vibration damper, comprising the following: a body section (110) into which a cylindrical coupling hole (111) penetrates vertically such that a piston rod (20) is connected to it; several internal grooves (120) which are concave along a circumferential direction of the coupling hole (111) and are arranged in a vertical direction; and an inner projection (130) which extends radially inwards from an inner peripheral surface of the inner groove (120), wherein a laterally projecting end of the inner projection (130) comes into close contact with an outer surface of the piston rod (20) when the body section (110) is compressed vertically; wherein the inner grooves (120) are formed continuously along the circumferential direction of the coupling hole (111) and a plurality of internal projections (130) are arranged along a circumferential direction of the internal grooves (120); wherein the inner projection (130) is inclined in the circumferential direction of the coupling hole (111) so that it forms a helical shape along the vertical direction of the coupling hole (111).

Description

BACKGROUND OF THE INVENTION AREA OF THE INVENTION

[0001] The present invention relates to a bumper rubber insert for a vibration damper and in particular to a bumper rubber insert for a vibration damper in which an inner projection extends from an inner peripheral surface to an inner groove and thus reduces the projection length of the inner projection, thereby minimizing a frictional connection or force-fit connection between a piston rod and a bumper rubber insert. DESCRIPTION OF THE STATE OF THE TECHNOLOGY

[0002] In general, a vibration damper, also called a shock absorber, is designed to suppress or reduce vibrations from a road surface. The vibration damper is positioned between a vehicle body or frame and a wheel to absorb vertical vibration energy from the vehicle body.

[0003] The vibration damper can increase durability by reducing dynamic stress on each part of a vehicle body, it can ensure the traction performance of a tire by suppressing movement of an unsprung mass, and it can improve the motion performance of a vehicle by suppressing changes in position caused by inertial forces.

[0004] The vibration damper has a cylinder, a piston valve that performs compression and rebound strokes within the cylinder, a piston rod, one end of which is connected to the piston valve and the other end of which is connected to the vehicle body, and a bumper rubber insert that absorbs a shock between the cylinder and the piston rod.

[0005] The bumper rubber insert has a coupling hole to which the piston rod is connected, and the bumper rubber insert is made of a material such as rubber or caoutchouc to allow compression and relaxation during strokes.

[0006] However, if the bumper rubber insert is compressed by a force applied in a vertical direction, and its inner peripheral surface is expanded radially inwards, an excessive contact pressure can be applied between the bumper rubber insert and the piston rod, creating a frictional or force-fit connection.

[0007] And if the contact pressure between the bumper rubber insert and the piston rod increases during compression, the inner peripheral surface of the bumper rubber insert may wear down. In this case, the bumper rubber insert may shift or become displaced, or its shock-absorbing performance may be impaired.

[0008] As one of the prior art documents relating to the present invention, Korean patent application publication No. KR 10 2002 0 045 773 A (published on June 20, 2002) discloses a bumper arrangement for a vibration damper.

[0009] DE 10 2010 039 621 A1 describes a damping element with a hollow cylindrical spring element and a support ring, wherein the spring element has a circumferential recess in the inner surface below the upper end face, and the support ring is mounted in this recess, wherein both the recess and the outer edge of the support ring are formed in a radially wave-like shape, wherein wave crests and wave troughs of the recess and support ring correspond to each other in shape, size and arrangement.

[0010] JP 2002-257 181 A describes a stop rubber with a plurality of projections extending axially in several positions around the circumferential direction of the inner circumference of a through-hole arranged for a damper rod. A longitudinal groove is formed between adjacent projections, and each projection is held in contact with the damper rod by a surface.

[0011] JP H11-44336A describes a bonded bumper attached to the upper part of a rod, such that the rod is inserted through the through-hole. Upon impact from the road surface, the outer cylinder of a shock absorber lifts, contacts the lower end of the bonded bumper, and compresses it axially to absorb the impact. During this compression, the outermost ends of the projections, which are separated axially and circumferentially and whose sides are tapered axially, are brought into contact with the outer circumferential surface of the rod. The contact area is reduced by the separation of the projections and the tapering, thus reducing friction between the rod and the bonded bumper. OVERVIEW OF THE INVENTION

[0012] One aspect of the present invention provides a bumper rubber insert for a vibration damper in which an inner projection extends from an inner peripheral surface of an inner groove, thus reducing the projection length of the inner projection. This reduces the contact pressure between a piston rod and the inner projection when the bumper rubber insert is compressed, thereby minimizing the frictional or force-fit connection between the piston rod and the bumper rubber insert.

[0013] In accordance with the present invention, a bumper rubber insert for a vibration damper with the features of claim 1 and a bumper rubber insert for a vibration damper with the features of claim 8 are provided.

[0014] Advantageous further training opportunities arise from the dependent sub-requirements. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a perspective view of a bumper rubber insert for a vibration damper in accordance with the present invention. Fig. Figure 2 is a cross-sectional view of the bumper rubber insert for the vibration damper in accordance with the present invention. Fig. Figure 3 is a cross-sectional view illustrating a condition in which an inner projection is formed obliquely in the bumper rubber insert for the vibration damper in accordance with the present invention. Fig. Figure 4 is a perspective view illustrating a state in which, furthermore, an outer projection is formed in the bumper rubber insert for the vibration damper in accordance with the present invention. DETAILED DESCRIPTION OF EXECUTION FORMS

[0015] Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0016] The advantages and features of the present invention and methods for achieving them will become more apparent from the following embodiments, which are described in detail in conjunction with the accompanying drawings.

[0017] However, it should be clear that the present invention is not limited to the following embodiments, and that various modifications can be made without derogating from the scope of protection of the present invention. The embodiments set forth herein are provided so that the present disclosure will be thorough and complete and will fully convey the concept of the invention to those skilled in the field. The present invention is to be defined by the attached claims.

[0018] Furthermore, detailed descriptions of generally known technologies or the like will be omitted, as these would unnecessarily obscure the subject matter of the present invention.

[0019] Fig. Figure 1 is a perspective view of a bumper rubber insert for a vibration damper in accordance with the present invention. Fig. Figure 2 is a cross-sectional view of the bumper rubber insert for the vibration damper in accordance with the present invention. Fig. Figure 3 is a cross-sectional view illustrating a condition in which an inner projection is formed obliquely in the bumper rubber insert for the vibration damper in accordance with the present invention, and Fig. Figure 4 is a cross-sectional view illustrating a state in which, furthermore, an outer projection is formed in the bumper rubber insert for the vibration damper in accordance with the present invention.

[0020] With reference to Fig. 1 and Fig. 2 The vibration damper in accordance with the present invention comprises a cylinder 10, a piston rod 20 and a bumper rubber insert 100.

[0021] The vibration damper in accordance with the present invention further comprises a piston valve (not illustrated) in the cylinder 10 in a state in which it is connected to an end of the piston rod 20, such that the interior of the cylinder 10 is divided into a compression chamber and a rebound chamber.

[0022] The vibration damper according to the present invention may further comprise an upper structure (isolater or the like) (not illustrated) configured to attach the piston rod 20 to a vehicle body, a dust cover (not illustrated) configured to cover the bumper rubber insert 100 and the upper end of the cylinder 10 from the outside, and upper / lower spring plates (not illustrated) installed on the cylinder 10 and the isolator, respectively, to support a helical suspension spring.

[0023] Among the components described above, cylinder 10 can have a cylindrical shape to form an interior space, and the interior space of cylinder 10 is filled with a fluid (O1, etc.).

[0024] One end of the cylinder 10 and one end of the piston rod 20, which will be described later, can each be connected to the vehicle body side or the wheel side of the vehicle to perform compression and rebound strokes.

[0025] One end of the piston rod 20 can be connected to the piston valve (not illustrated), and the other end of the piston rod 20 can extend to the outside of the cylinder 10 and be connected to the vehicle body side or the wheel side of the vehicle.

[0026] The piston valve divides the interior of the cylinder 10 into the compression chamber and the rebound chamber and generates a damping force due to the resistance of a fluid as it moves back and forth in the cylinder 10 in one direction of the compression and rebound strokes.

[0027] The bumper rubber insert 100 is installed between a lower end of the upper structure and the cylinder 10 and absorbs a shock that is transferred in a vertical direction through compression and relaxation processes.

[0028] For this purpose, the bumper rubber insert 100 is made of an elastic shock-absorbing material, such as rubber, so that the bumper rubber insert 100 relaxes back into its original shape after absorbing a shock that has been transferred in a vertical direction during compression.

[0029] In particular, the bumper rubber insert 100 has a body section 110, an inner groove 120 and a multitude of inner projections 130.

[0030] In the bumper rubber insert 100, the upper end of the body section 110 is arranged on the side of the upper structure, and the lower end of the body section 110 is arranged on the cylinder side. A coupling hole 111 penetrates the body section 110 vertically such that the piston rod 20 penetrates the coupling hole 111 vertically and is connected to it.

[0031] The coupling hole 111 can form a circumferential surface in the horizontal direction, and the coupling hole 111 can be formed such that it has an inner peripheral surface that is equal to or greater than a diameter of the piston rod 20.

[0032] When the bumper rubber insert 100 is compressed, the inner peripheral surface of the coupling hole 111 expands radially inwards to come into close contact with the outer peripheral surface of the piston rod 20 under a certain pressure.

[0033] The lower end section of body segment 110 can have a shape in which its diameter is gradually reduced. However, various shapes can be applied to body segment 110.

[0034] The inner groove 120 is formed concavely along the inner peripheral surface of the coupling hole 111. One or more inner grooves 120 can be arranged along the vertical direction of the coupling hole 111.

[0035] Preferably the inner grooves 120 are formed continuously along the circumferential direction of the coupling hole 111, but the inner grooves 120 can also be arranged intermittently along the circumferential direction of the coupling hole 111.

[0036] The inner groove 120 can be formed such that it has a concave curved surface along the vertical direction of the coupling hole 111.

[0037] In this case, the upper and lower ends of the inner groove 120 can be connected to the inner peripheral surface of the coupling hole 111, while forming a convexly curved surface.

[0038] For example, in a case where the multitude of inner grooves 120 are arranged along the vertical direction of the coupling hole 111, the adjacent ends of the inner grooves 120 can be connected to each other while forming a convexly curved surface.

[0039] The inner projections 130 are formed on the inner peripheral surface of the inner groove 120. The inner projections 130 extend convexly radially inwards from the inner peripheral surface of the inner groove 120.

[0040] When the bumper rubber insert 100 is compressed vertically, the protruding ends of the inner projections 130 extend further radially inwards from the coupling hole 111 and come into close contact with the outer surface of the piston rod 20.

[0041] In this case, it is preferable that the plurality of internal projections 130 is arranged along the circumferential direction of the internal groove 120, but the internal projections 130 can also be arranged intermittently along the circumferential direction of the internal groove 120.

[0042] The projecting ends of the inner projections 130 can be formed such that they have a convexly curved surface in the vertical direction and the circumferential direction of the coupling hole 111.

[0043] Since the inner projections 130 are arranged on the inner peripheral surface of the inner groove 120, the projecting ends of the inner projections 130 are spaced from the piston rod 20 by the depth of the inner groove 120.

[0044] As in Fig. 1 and Fig. As illustrated in Figure 2, the inner projections 130 can be formed in such a way that they have an oval shape which has a length along the vertical direction of the coupling hole 111.

[0045] Thus, if the inner projections 130 are formed in such a way that they have an oval shape, the protruding ends of the inner projections 130 can first come into close contact with the outer peripheral surface of the piston rod 20 with the smallest area.

[0046] The projecting ends of the inner projections 130 can extend radially inwards further than the upper and lower ends of the inner groove 120 and first come into close contact with the outer peripheral surface of the piston rod 20.

[0047] In contrast, internal projections 130-1 can be formed such that they are inclined in the circumferential direction of the coupling hole 111 in order to form a helical shape along the vertical direction of the coupling hole 111.

[0048] As in Fig. As illustrated in Figure 3, the inner projections 130-1 can, if the inner projections 130-1 are formed in such a way that they are inclined, have a length which is inclined in an oblique direction while forming the same width.

[0049] For example, when the bumper rubber insert 100 is compressed and the inner peripheral surface of the coupling hole 111 expands radially inwards, the projecting ends of the inner projections 130-1 come into close contact with the outer peripheral surface of the piston rod 20 in a helical shape. As a result, the bumper rubber insert 100 can be rotated around the piston rod 20 by a pitch due to the frictional force.

[0050] When the bumper rubber insert 100 is vertically compressed, the protruding ends of the inner projections 130 and 130-1 come into close contact with the outer peripheral surface of the piston rod 20.

[0051] Since in this case the inner projections 130 and 130-1 are arranged on the inner peripheral surface of the inner groove 120, it is possible to prevent a contact pressure between the piston rod 20 and the inner projections 130 and 130-1 from increasing excessively over a certain area.

[0052] On the other hand, a concave outer groove 140 can be continuously formed on the outer surface of the body section 110 along the circumferential direction. A plurality of concave outer grooves 140 can be arranged along the vertical direction.

[0053] The outer groove 140 can form a concave curved surface in the vertical direction, and the upper and lower ends of the outer groove 140 can be connected to form a convex curved surface with the outer surface of the body section 110.

[0054] As in Fig. As illustrated in Figure 2, the outer groove 140 can be located in a section between the upper end and the lower end of the inner groove 120. In this case, the diameter of the outer groove 140 is relatively smaller than the outer diameter of the bumper rubber insert 100.

[0055] When the bumper rubber insert 100 is compressed, the outer groove 140 forms a section in which the bumper rubber insert 100 can contract strongly along the vertical direction.

[0056] Furthermore, an air channel 150 can be formed concavely at the upper end of the body section 110, so that the air inside the coupling hole 111 can be vented to the outside.

[0057] The air duct 150 can be divided into a horizontal section 151, which is formed horizontally, and a vertical section 152, which is connected vertically to the horizontal section 151.

[0058] The horizontal section 151 is concave at the upper end of the body section 110. One end of the horizontal section 151 communicates with the coupling hole 111 and the other end of the horizontal section 151 communicates with the outside of the body section 110.

[0059] That is, if the upper end of the bumper rubber insert 100 comes into close contact with the upper structure (insulator or the like), then the lower surface of the horizontal section 151 is spaced away from the upper structure, thus maintaining the space in which the air can move.

[0060] The vertical section 152 extends in such a way that it is bent downwards in a state in which it is connected to an end of the horizontal section 151, which extends outwards from the body section 110. As a result, the vertical section 152 is formed concavely on the outer surface of the body section 110.

[0061] In this case, the vertical section 152 has a certain length along the vertical direction and is exposed on the side of the body section 110. Therefore, even when the bumper rubber insert 100 is compressed, the space in which the air can move is maintained.

[0062] Since the air duct 150 connects the coupling hole 111 to the outside in a communicating manner and forms a ventilation duct or air ventilation duct, the bumper rubber insert 100 can easily perform compression and relaxation processes.

[0063] Furthermore, one or more upper projections 160 may be formed on the inner peripheral surface of the coupling hole 111. The upper projections 160 may be spaced apart from each other on the upper section of the inner groove 120.

[0064] Preferably, the protruding end of the upper projection 160 comes into close contact with the outer surface of the piston rod 20, but it can also be spaced a certain distance away from the outer surface of the piston rod 20.

[0065] When the plurality of upper projections 160 is formed, one or more of the upper projections 160 can be arranged on the same line as the air duct 150 with respect to a vertical central axis line C of the plurality of coupling holes 111.

[0066] Alternatively, a contact end 112 can be formed in a lower section of the body section 110. The contact end 112 is curved towards the central axis of the coupling hole 111, and a lower section of the contact end 112 comes into close contact with the upper end of the cylinder 10.

[0067] Preferably, the contact end 112 is formed such that it has a curved surface such that the outer diameter of the contact end 112 is gradually reduced towards the lower section. However, various shapes can be used for the contact end 112.

[0068] Furthermore, as in Fig.As illustrated in Figure 4, a plurality of external projections 170 on the outer surface of the contact end 112 are arranged along the circumferential direction such that the contact end 112 comes into close contact with the upper end of the cylinder 10 when the bumper rubber insert 100 is compressed.

[0069] The outer projection 170 can be shaped such that it has a convexly curved surface in the vertical and circumferential directions. In particular, the outer projection 170 can be shaped such that it has an oval shape with a length along the vertical direction of the coupling hole 111.

[0070] This means that when the bumper rubber insert 100 is compressed vertically, the outer projection 170 comes into close contact with the upper end of the cylinder 10, thereby reducing the contact area between the cylinder 10 and the bumper rubber insert 100 and minimizing a frictional connection or force-fit connection when the bumper rubber insert 100 is compressed.

[0071] Consequently, in accordance with the present invention, because the inner projections 130 and 130-1 protrude from the inner peripheral surface of the inner groove 120, the projection length of the inner projections 130 and 130-1 is reduced. Therefore, when the bumper rubber insert 100 is compressed, the contact pressure between the piston rod 20 and the inner projections 130 and 130-1 can be reduced, thereby minimizing a frictional connection or force-fit connection between the piston rod and the bumper rubber insert.

[0072] Furthermore, in accordance with the present invention, since the contact pressure between the piston rod 20 and the bumper rubber insert 100 can be reduced, it is possible to prevent the contact surface of the bumper rubber insert 100, which comes into close contact with the outer peripheral surface of the piston rod 20, from wearing out quickly.

[0073] The bumper rubber insert for the vibration damper in accordance with specific embodiments of the present invention has been described, but it is clear that various modifications can be made to it without deviating from the scope of protection of the present invention.

[0074] Therefore, the scope of protection of the present invention is not to be limited to the embodiments described above, and is determined by the attached claims and by equivalents thereof.

[0075] Although the embodiments of the present invention have been described with reference to the specific embodiments, it will be clear to those skilled in the art that various changes and modifications can be made without departing from the inventive concept and the scope of protection of the invention as defined in the following claims. DESCRIPTION OF REFERENCE MARK 10 cylinders 100 bumper rubber inserts 111 Coupling hole 120 inner groove 140 outer groove 151 horizontal section 20 piston rod 110 bodies 112 End of contact 130, 130-1 inside lead 150 air duct 152 vertical section 160 upper lead C Center axis line 170 outside lead

Claims

[1] Bumper rubber insert (100) for a vibration damper, comprising the following: a body section (110) into which a cylindrical coupling hole (111) penetrates vertically such that a piston rod (20) is connected to it; several internal grooves (120) which are concave along a circumferential direction of the coupling hole (111) and are arranged in a vertical direction; and an inner projection (130) which extends radially inwards from an inner peripheral surface of the inner groove (120), wherein a laterally projecting end of the inner projection (130) comes into close contact with an outer surface of the piston rod (20) when the body section (110) is compressed vertically; wherein the inner grooves (120) are formed continuously along the circumferential direction of the coupling hole (111) and a plurality of internal projections (130) are arranged along a circumferential direction of the internal grooves (120); wherein the inner projection (130) is inclined in the circumferential direction of the coupling hole (111) so that it forms a helical shape along the vertical direction of the coupling hole (111). [2] Bumper rubber insert (100) according to claim 1, wherein the inner groove (120) is formed such that it has a concave curved surface along a vertical direction of the coupling hole (111). [3] Bumper rubber insert (100) according to claim 1, wherein the protruding end of the inner projection (130) forms a convexly curved surface in the vertical direction and the circumferential direction of the coupling hole (111). [4] Bumper rubber insert (100) according to claim 3, wherein the inner projection (130) is formed such that it has an oval surface with a length along the vertical direction of the coupling hole (111). [5] Bumper rubber insert (100) according to claim 1, wherein the projecting end of the inner projection (130) projects radially inwards further than the upper and lower ends of the inner groove (120). [6] Bumper rubber insert (100) according to claim 1, wherein outer grooves (140) are continuously formed on the outer surface of the body section (110) along the circumferential direction and the outer grooves (140) are arranged in a section between the upper end and the lower end of the inner groove (120). [7] Bumper rubber insert (100) according to claim 6, which further comprises one or more upper projections (160) on the inner peripheral surface of the coupling hole (111), wherein one or more upper projections (160) are spaced apart from each other in an upper section of the inner groove (120) and come into contact with the outer surface of the piston rod (20) and the upper projections (160) are arranged on the same line as an air duct (150) with respect to a vertical center line of the coupling hole (111). [8] Bumper rubber insert (100) for a vibration damper, comprising the following: a body section (110) into which a cylindrical coupling hole (111) penetrates vertically such that a piston rod (20) is connected to it; several internal grooves (120) which are formed concavely along a circumferential direction of the coupling hole (111) and are arranged in a vertical direction; an inner projection (130) that extends radially inwards from an inner peripheral surface of the inner groove (120), wherein a laterally projecting end of the inner projection (130) comes into close contact with an outer surface of the piston rod (20) when the body section (110) is compressed vertically; and a contact end (112) on a lower side of the body section (110), wherein the contact end (112) is curved in the direction of a central axis of the coupling hole (111), a lower section of the contact end (112) comes into close contact with an upper end of a cylinder and a plurality of external projections (170) are arranged on an outer surface of the contact end (112) along a circumferential direction to come into close contact with the upper end of the cylinder when the bumper rubber insert (100) is compressed. [9] Bumper rubber insert (100) according to claim 8, wherein the outer surface of the contact end (112) is formed such that it has a convexly curved surface in the vertical direction, and the outer projection (170) forms a convexly curved surface in the vertical direction and the circumferential direction.

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