Bushing device for an eye section of a leaf spring

Abstract

A bushing device for an eye portion (4) of a leaf spring (2) used in a suspension of a vehicle, comprising: a first bushing (6) adapted to be inserted into the eye portion (4), second bushings (10) which are respectively arranged near both side surfaces of the eye portion (4), each of the second bushings having a hole (12) formed at a central portion thereof, and a leaf spring fixing holding part into which the second bushings (10) are inserted, wherein an inner tube (14) is inserted into the holes (12) of the second bushings (10) and wherein head portions are formed respectively at both ends of the inner tube (14) in a circumferential direction and each head portion extends with a certain length in a radial direction.

Description

Background of the disclosure / inventionField of the disclosure / invention

[0001] The present disclosure / invention relates to a bushing device for an eye portion of a leaf spring, and more particularly to a bushing device in which a rubber bushing and a copper alloy bushing are simultaneously used on an eye portion of a leaf spring connected to a suspension system of a vehicle. Description of the technology used

[0002] As it is in the Fig. 1, a leaf spring of a vehicle usually has an eye portion formed thereon to connect an axle and a vehicle body and to keep it rotatable about the axle.

[0003] The type of bushing used in the eye section is mainly divided into rubber bushing and copper alloy bushing.

[0004] Although the rubber bushing has the advantage of effectively absorbing shock, there is a problem that breakage or loosening may occur because its durability is comparatively low.

[0005] The copper alloy bushing has relatively good durability, but has a disadvantage in absorbing shock. State of the art document: JP 3 719 030 B2

[0006] Furthermore, for example, from US 5 337 997 A, US 3 434 707 A, DE 42 05 302 A1 and DE 12 17 700 B each a bushing device for an eye portion of a leaf spring is known, which is used in a suspension of a vehicle, the bushing device comprising: a first bushing which is adapted to be inserted into the eye portion, second bushings which are respectively arranged near both side surfaces of the eye portion, each of the second bushings having a hole formed at a central portion thereof, and a leaf spring fixing holding part into which the second bushings are inserted. Explanation of the disclosure / invention

[0007] The present disclosure / invention is intended to solve the above-mentioned problems, and it is an object of the present disclosure / invention to provide a bushing device that effectively absorbs shock and has excellent durability by using a configuration in which a rubber bushing and a copper alloy bushing (e.g., brass bushing) are simultaneously used at an eye portion of a leaf spring used in a suspension system (hereinafter, suspension) of a vehicle (e.g., motor vehicle).

[0008] To achieve the above-mentioned object, a bushing device having the features according to claim 1 is provided. Further developments of the bushing device are described in the dependent claims. That is, a bushing device for an eyelet portion of a leaf spring used in a suspension of a vehicle comprises: a first hollow bushing or bush (hereinafter referred to as a bushing) configured to be inserted into the eyelet portion; second bushings respectively disposed near both side surfaces of the eyelet portion (e.g., the second bushings are respectively disposed adjacent to the side surfaces, e.g., with a predetermined interval), each of the second bushings having a hollow hole (e.g., through hole; hereinafter referred to as a hole) formed at a central portion thereof; and a leaf spring fixing support member into which the second bushings are inserted.

[0009] For example, a hollow tube pin or a tubular hollow pin (hereinafter referred to as: tubular pin) can be inserted into the first socket.

[0010] A (respective) hollow inner tube (hereinafter referred to as inner tube) is inserted into the holes of the second bushings.

[0011] Head parts (e.g. collar or flange parts) are formed at both ends of the inner tube in a circumferential direction, and each head part extends with a certain length in a radial direction (e.g. forming a flange).

[0012] For example, the eye portion and the second bushings may be coupled to each other by a coupling or connecting screw (hereinafter referred to as coupling screw) which successively passes through the inner tube coupled to one of the second bushings, the tube pin and the inner tube coupled to the other of the second bushings.

[0013] For example, both ends of the tube pin may be in contact with and fixed to the head portions of the inner tubes by an axial force generated by a coupling between the coupling screw and a nut.

[0014] For example, the leaf spring fixing holding part may be configured to be divided into a first housing and a second housing.

[0015] For example, each of the first housing and the second housing may have a space formed therein and be configured to receive the eye portion (e.g., the space is configured to receive the eye portion).

[0016] For example, a socket receiving portion configured to receive the second socket therein may be formed in each of two side walls of each of the first housing and the second housing, which walls are placed near both side surfaces of the eye portion.

[0017] For example, the first bushing may have a circular cross-section and the bushing receiving portion may have a semicircular groove formed thereon / in it having a semicircular cross-section.

[0018] For example, on a lower surface of each of the two side walls of the first housing or the second housing, screw recesses having a predetermined length (e.g., depth) may be formed at portions spaced from the socket receiving portion toward a front end and a rear end (e.g., a direction transverse to an extending direction of the sockets) by a predetermined distance.

[0019] For example, in the first housing or the second housing, screw holes may be formed at portions spaced from the socket receiving portion toward the front end and the rear end.

[0020] For example, a screw passing through the screw hole may be screw-coupled to the screw recess of the first housing or the second housing having a thread formed on an inner side thereof.

[0021] For example, the first bushing may be a copper alloy bushing (e.g. brass bushing) and the second bushing may be a rubber bushing. Short description of the drawings Fig. 1 is a view illustrating a conventional bushing device for an eye portion of a leaf spring. Fig. 2 is a conceptual view (exploded view) of a bushing device for the eye portion of a leaf spring according to the present disclosure / invention. Fig. 3 is a perspective view of the bushing device for the eye portion of the leaf spring according to the present disclosure / invention. Fig. 4 is a cross-sectional view of the bushing device for the eye portion of the leaf spring according to the present disclosure / invention. Detailed description of specific embodiments

[0022] In order to fully understand the present disclosure, preferred embodiments thereof are described with reference to the accompanying drawings. The embodiments of the present disclosure can be modified in various ways, and the scope of the present disclosure / invention should not be construed as limited to the embodiments described in detail below. The present embodiments are provided to enable those skilled in the art to better understand the present disclosure. Therefore, shapes and the like of elements in the drawings may be exaggerated for clarity. It should be understood that the same elements in the drawings are denoted by the same reference numerals.Descriptions of well-known functions and configurations that would unnecessarily obscure the scope of the present disclosure / invention are omitted.

[0023] The present disclosure / invention relates to a bushing device for an eye portion of a leaf spring, and more particularly to a bushing device in which a rubber bushing and a copper alloy bushing are simultaneously used in an eye portion of a leaf spring connected to a suspension of a vehicle.

[0024] The Fig. 2 shows a conceptual view of a bushing device for an eye portion of a leaf spring according to the present disclosure / invention, and the Fig. 3 shows a perspective view of the bushing device for the eye portion of the leaf spring according to the present disclosure / invention.

[0025] Bushings (e.g. bearing bushings, e.g. plain bearing bushings) made of different materials include a first bushing 6 made of a copper alloy material and a second bushing 10 made of a rubber material, and are simultaneously coupled to the leaf spring 2 according to the present disclosure / invention.

[0026] The Fig. 4 shows a cross-sectional view of the bushing device for the eye portion of the leaf spring according to the present disclosure / invention.

[0027] The first bushing 6, which has a central axis that is the same as a central axis of a boss portion 4 and which has a circular cross section, is inserted into and coupled to the inside of the boss portion 4. The first bushing 6 is shaped to have an axial length that is equal to an axial length of the boss portion 4.

[0028] A tubular pin 8, which has a central axis the same as the central axis of the first bushing 6, is inserted into and coupled to the first bushing 6. An axial length of the tubular pin 8 is greater than the axial length of the first bushing 6, so that when the tubular pin 8 is inserted into the first bushing 6, both end portions of the tubular pin 8 protrude at both ends of the eye portion 4 by the same length.

[0029] The second bushings 10 are formed or arranged near (e.g., respectively adjacent to) the two side surfaces of the eye portion 4, and each second bushing is formed in a shape to have a circular cross section and to extend with a predetermined length in an axial direction thereof.

[0030] A hole 12 is formed in a central portion of the second bushings 10 to penetrate through both end surfaces of the second bushings 10 in the axial direction of the second bushings 10. An inner tube 14, which has a central axis the same as a central axis of the second bushing 10, is inserted into the hole 12 of the second bushing 10.

[0031] Head portions 16 are formed respectively at both ends of the inner tube 14 in a circumferential direction, and each head portion extends in a radial direction with a predetermined length to have a circular shape. The head portion 16 is configured to have a diameter larger than an inner diameter of the eye portion 4 of the leaf spring 2.

[0032] Coupling of the eye portion 4 and the second bushings 10 is carried out by a coupling screw 18 which passes through the inner tube 14 and the tube pin 8.

[0033] In other words, the coupling screw 18 sequentially passes through the inner tube 14 coupled to one of the second bushings 10, the tube pin 8, and the inner tube 14 coupled to the other of the second bushings 10, and a nut 20 is then coupled to one end portion of the coupling screw to couple the eye portion 4 and the second bushings 10 arranged at both end portions of the eye portion 4.

[0034] The central axis of the inner tube 14 is arranged coaxially with the central axis of the first bushing 6 by the above coupling, and both ends of the tube pin 8 are brought into contact with and fixed to the head portions 16 of the inner tubes 14 by an axial force generated by coupling the coupling bolt 18 and the nut 20.

[0035] The first bushing 6 does not apply any torsional force to the second bushing 10 and is set to be non-rotatable with respect to the eye portion 4, and thus the first bushing 6 is slidably rotatable about the tubular pin 8 as a rotation axis.

[0036] A leaf spring fixing holding part, into which the second bushing 10 is inserted, is formed outside the eye portion 4 to which the first bushing 6 and the second bushing 10 are coupled.

[0037] The leaf spring fixing holding member is formed to be divided into a first housing 22 and a second housing 32, and each of the first housing 22 and the second housings 32 has a space formed therein to accommodate the eye portion 4.

[0038] The first housing 22 is coupled to an upper side of the eye portion 4 to which the first bushing 6 and the second bushing 10 are simultaneously coupled, and the second housing 32 (or the second housings 32), which is coupled at an upper end thereof to a lower portion of the first housing 22, is coupled to a lower side of the eye portion 4.

[0039] Although the drawings illustrating an embodiment of the present disclosure / invention show a configuration in which the first housing 22 is placed at an upper portion of the leaf spring 2 and the second housing 32 is placed at a lower portion of the leaf spring 2, this configuration is merely an embodiment, and positions of the first housing 22 and the second housing 32 may be interchanged.

[0040] The first housing 22 is formed in a shape in which the lower portion is open and a space is formed therein, and therefore the eye portion 4 and the upper end of the second bushing 10 are arranged in the first housing 22.

[0041] Bushing receiving portions 24 are formed in the two side walls of the first housing 22, which are respectively placed near the two side surfaces of the eye portion 4, and upper semicircular portions of the second bushings 10 are respectively received in the above bushing receiving portions 24.

[0042] Each of the socket receiving portions 24 is formed in a shape in which a side wall of the first housing 22 is removed / recessed upward from a lower surface thereof, an edge portion of the second socket 10 in the socket receiving portion in a front-rear direction (see, for example, Fig. 3: left upper side (≙ front) and right lower side (≙ rear)) and the socket receiving portion is formed to have a shape and a size to allow the upper semicircular portion of the second socket 10 to be received therein without a gap.

[0043] A semicircular groove 26 having a semicircular cross section and a central axis coaxial with the central axis of the inner tube 14 is formed on a portion of each of the side walls of the first housing 22 where the socket receiving portion 24 is formed.

[0044] The semicircular groove 26 formed in the first housing 22 is formed in a shape of a through groove (e.g., semicircular circumferential groove) which penetrates the side wall of the first housing 22 in an axial direction of the eye portion 4 (e.g., is recessed in the side wall of the first housing 22).

[0045] Openings 30 are formed in a front wall and a rear wall of the first housing 22, respectively, and each of the openings is formed in a shape in which each is removed / recessed upward from the front and rear walls from a lower end.

[0046] The openings 30 are configured to allow a portion of the leaf spring 2 extending from the eye portion 4 to be inserted therein. When the eye portion 4 is rotated, a position of the portion of the leaf spring 2 extending from the eye portion 4 is changed in a vertical direction. Therefore, the openings 30 are means for preventing the first housing 22 from interfering with a position change of the leaf spring 2.

[0047] The first housing 22 may be shaped to form a -shaped cross-section which is open towards the eye portion 4, as shown in the figure (e.g. Fig. 4), and, if the first housing 22 is shaped to form a shape, the socket receiving portions 24 may be formed in the two side walls defining the opening (e.g., therebetween).

[0048] On a lower surface of each of the two side walls of the first housing 22, screw recesses 28 with a predetermined length extending toward an upper portion of the first housing 22 are formed at portions spaced from the socket receiving portion 24 toward a front end and a rear end, respectively, by a predetermined distance. A thread is formed on an inner peripheral surface of each of the screw recesses 28.

[0049] The second housings 32 are respectively coupled to the second sockets 10. The second housing 32 is upwardly open, and a socket receiving portion 34 is formed in the second housing to receive a lower semicircular portion of the second socket 10 therein.

[0050] An edge portion of the second socket 10 is in the socket receiving portion 34 in a front-rear direction (compare, for example, Fig.3: left upper side (≙ front) and right lower side (≙ rear)) thereof, and the socket receiving portion 34 is formed to have a shape and a size to allow the lower semicircular portion of the second socket 10 to be received therein without a gap.

[0051] In each of the second housings 32, a semicircular groove 36 having a semicircular cross section and a central axis arranged coaxially with the central axis of the inner tube 14 is formed in each of the two side walls (e.g., of the respective second housing) forming the socket receiving portion 34.

[0052] The semicircular groove 36 formed in each of the second housings 32 is formed in the shape of a through groove (e.g., semicircular circumferential groove) which penetrates both side walls of the second housing 32 in the axial direction of the boss portion 4 (e.g., is recessed in the side wall of the second housing 32).

[0053] In each of the second housings 32, screw holes 38 penetrating through the second housing 32 are formed at portions spaced from the socket receiving portion 34 toward a front end and a rear end by a certain distance.

[0054] The second housings 32 are respectively coupled to the two side walls of the first housing 22, and the first housing 22 and the second housing 32 are coupled to each other by screw coupling of a screw passing through the screw hole 38 of the second housing 32 to the screw recess 28 of the first housing 22 having a thread formed on an inner side thereof.

[0055] When the first housing 22 and the second housing 32 are coupled to each other, the semicircular groove 26 of the first housing 22 and the semicircular groove 36 of the second housing 32 form a circular space having a diameter larger than that of the head part 16, and therefore, a head portion of the coupling screw 18 and the groove 20 are placed within the circular space formed by the semicircular grooves 26 and 36.

[0056] The coupling screw 18 and the tubular pin 8 may be attached to the first housing 22 and the second housing 32 through the second bushing(s) 10 to absorb a shock to the eye portion 4 of the leaf spring 2.

[0057] Furthermore, the second bushing 10, which is attached to the first housing 22 and the second housing 32, can absorb shock transmitted from a road surface and is attached to the first housing 22 and the second housing 32 without a gap. As a result, elastic torsional deformation (of the second bushing) is not generated, thereby increasing durability.

[0058] According to the present disclosure / invention, an advantage is achieved that by applying the rubber bushing to the eye portion of the leaf spring connected to the suspension of the vehicle, it is prevented from transmitting a shock from a road surface to the vehicle body, and by simultaneously applying the copper alloy bushing to the eye portion, it is possible to reduce a load due to elastic rotational deformation of the rubber bushing, thereby increasing the durability of the copper alloy bushing and the rubber bushing.

[0059] If the service life of the copper alloy bushing and the rubber bushing is increased, there is an advantage in that it is possible to reduce costs for ensuring quality and maintenance costs.

[0060] The above-described embodiments of the bushing device for the eye portion of the leaf spring of the present disclosure / invention are merely exemplary in nature. It is therefore readily understood that the present disclosure / invention is not limited only to the embodiments discussed in the foregoing description.

Claims

[1] A bushing device for an eye portion (4) of a leaf spring (2) used in a suspension of a vehicle, comprising: a first bushing (6) adapted to be inserted into the eye portion (4), second bushings (10) which are respectively arranged near both side surfaces of the eye portion (4), each of the second bushings having a hole (12) formed at a central portion thereof, and a leaf spring fixing holding part into which the second bushings (10) are inserted, wherein an inner tube (14) is inserted into the holes (12) of the second bushings (10) and wherein head portions are formed respectively at both ends of the inner tube (14) in a circumferential direction and each head portion extends with a certain length in a radial direction. [2] The bushing device for the eye portion (4) of the leaf spring (2) according to claim 1, wherein a tubular pin (8) is inserted into the first bushing (6). [3] The bushing device for the eye portion (4) of the leaf spring (2) according to any one of the preceding claims, wherein the eye portion (4) and the second bushings (10) are coupled to each other by a coupling screw (18) which sequentially passes through the inner tube (14) coupled to one of the second bushings (10), the tube pin (8) and the inner tube (14) coupled to the other of the second bushings (10). [4] The bushing device for the eye portion (4) of the leaf spring (2) according to claim 3, wherein both ends of the tube pin (8) are in contact with and fixed to the head portions of the inner tubes (14) by an axial force generated by coupling between the coupling bolt (18) and a nut (20). [5] The bushing device for the eye portion (4) of the leaf spring (2) according to any one of the preceding claims, wherein the leaf spring fixing holding member is arranged to be divided into a first housing (22) and a second housing (32). [6] The bushing device for the eye portion (4) of the leaf spring (2) according to claim 5, wherein each of the first housing (22) and the second housing (32) has a space formed therein and is adapted to receive the eye portion (8). [7] The bushing device for the eye portion (4) of the leaf spring (2) according to claim 5 or 6, wherein a bushing receiving portion (24, 34) adapted to receive the second bushing (10) therein is formed in each of two side walls of each of the first housing (22) and the second housing (32) which are placed near the two side surfaces of the eye portion (8). [8] The bushing device for the eye portion (4) of the leaf spring (2) according to claim 7, wherein the first bushing (6) has a circular cross section and the bushing receiving portion (24, 34) has a semicircular groove (26, 36) formed thereon which has a semicircular cross section. [9] The bushing device for the eyelet portion (4) of the leaf spring (2) according to claim 7 or 8, wherein on a lower surface of each of the two side walls of the first housing (22) or the second housing (32), screw recesses (28) are formed with a predetermined length at portions spaced from the bushing receiving portion (24, 34) toward a front and rear end. [10] The bushing device for the eye portion (4) of the leaf spring (2) according to any one of claims 7 to 9, wherein screw holes (38) are formed in the first housing (22) or the second housing (32) at portions spaced from the bushing receiving portion (24, 34) toward the front and rear ends. [11] The bushing device for the eye portion (4) of the leaf spring (2) according to claim 10, wherein a screw passing through the screw hole (38) is screw-coupled with the screw recess (28) of the first housing (22) or the second housing (32) having a thread formed on an inner side thereof. [12] The bushing device for the eye portion (4) of the leaf spring (2) according to any one of the preceding claims, wherein the first bushing (6) is a copper alloy bushing and the second bushing (10) is a rubber bushing.

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