Articulated yoke for a rear axle steering system

Abstract

The invention relates to an articulated yoke (1) for a rear axle steering system of a motor vehicle, comprising an asymmetrically designed main body (2) which has an opening (6) for inserting a central screw (7) oriented normally to a reference plane (BE) of the main body (2), wherein a connection plane (AE) of the main body, said plane being at an angle to the reference plane (BE), is parallel to the centre axes (A11, A12) of two pins (11, 12) inserted into the main body (2), and wherein a U-shaped sheet-metal connecting piece (13), the U-legs (8, 9) of which are designed as mutually parallel cheeks which have mutually aligned openings (18, 19), is supported on the main body (2) by means of a U-base (14) which connects the U-legs (8, 9) to one another and which extends tangentially to the connection plane (AE), wherein at the same time the two pins (11, 12), which are each arranged at the transition between the U-base (14) and one of the U-legs (8, 9), block any displacements of the sheet-metal connecting piece (13) along a reference axis (BA) running centrally through said openings (18, 19).

Description

[0001] Articulated link for a rear axle steering system

[0002] The invention relates to a rear axle steering system and a joint fork designed for installation in a rear axle steering system of a motor vehicle.

[0003] German patent application DE 102016204568 A1 discloses a screw connection between a first, fork-shaped component and a second, rod-shaped component by means of a screw bolt. The screw connection according to DE 102016204568 A1 is intended for use in a wheel suspension of a motor vehicle and provides that cylindrical mating surfaces are formed on the aforementioned components.

[0004] German patent DE 102017201 352 A1 discloses an actuator intended for use in the rear axle steering system of a motor vehicle, which comprises a joint fork connected to a spindle. The joint fork according to DE 102017201 352 A1 is constructed in multiple parts and has two parallel cheeks and a web connecting the cheeks. One of the two cheeks is integrally connected to the web, while the other cheek is designed as a separate component.

[0005] A flange drive for a universal joint described in DE 10037866 A1 comprises two joint fork halves, each joint fork half having a foot part and a bearing part. The joint fork halves can be connected to each other in the area of ​​their foot part to form a flange part.

[0006] German patent DE 102018 129288 A1 discloses a rear axle steering system for a vehicle with a tie rod assembly. In this system, a connecting section of a fork element is held to a fork connection of the tie rod assembly by means of a screw bolt. The angle between the fork element and the fork connection is variable and can be fixed by means of the screw bolt. The invention is based on the objective of providing a joint fork that is further developed compared to the aforementioned prior art, particularly robust, and at the same time easy to manufacture, and suitable for use in a rear axle steering system of a motor vehicle.

[0007] This problem is solved according to the invention by a joint fork with the features of claim 1. According to claim 8, the joint fork is particularly suitable for use in a rear axle steering system.

[0008] The articulated fork, designed for installation in the rear axle steering system of a motor vehicle, comprises an asymmetrically shaped base body with an opening for inserting a central bolt oriented perpendicular to a reference plane of the base body. A connecting plane of the base body, inclined to the reference plane, is aligned parallel to the center axes of two pins inserted into the base body. A U-shaped sheet metal connector, also part of the articulated fork, has two U-shaped legs in the form of parallel cheeks. These two cheeks contain aligned openings. Furthermore, the U-shaped sheet metal connector has a U-shaped base connecting the U-shaped legs, which is tangent to the connecting plane and is supported by the base body.The aforementioned pins are each located at the transition between the U-base and one of the U-legs and block any displacement of the sheet metal connector along a reference axis placed centrally through the aforementioned openings.

[0009] The radius of curvature on the inside of the U-shaped sheet metal connector in the transition area between the U-base and the U-leg can correspond to the radius of the pin. In particular, precisely matched contours in this area can be achieved through precision machining. The entire U-shaped sheet metal connector can have a uniform wall thickness. The diameter of the pins that hold the U-shaped sheet metal connector in a defined position can be larger than the wall thickness of the sheet metal connector.

[0010] In various possible configurations of the articulated fork, its fork-shaped U-shaped legs are of equal length. Regarding the attachment of the sheet metal connector, including the U-shaped legs, to the base body, press-fitting is particularly suitable. In this case, the areas of the base body into which the pins are pressed can block any movement of the sheet metal connector in the longitudinal direction of the pins. The longitudinal axes of the two pins lie in a plane to which the aforementioned reference axis is parallel.

[0011] Regarding possible methods for manufacturing the base body of the articulated fork, a wide variety of known manufacturing processes can be used. In particular, machining or post-processing of the base body is possible. The base body and the U-shaped sheet metal connector, which can be manufactured using forming processes, can be made from the same material or from different materials.

[0012] In all its embodiments, the articulated fork is characterized by a robust design that virtually eliminates the possibility of incorrect assembly. The articulated fork is not only suitable for use in an electromechanically actuated rear axle steering system of a motor vehicle, but can also be installed, for example, in a steer-by-wire system to steer the front wheels of a vehicle. Stationary applications of the articulated fork, such as in an actuating mechanism of an industrial plant, are also possible.

[0013] An embodiment of the invention is explained in more detail below with reference to a drawing. Figure 1 shows a sectional view of a articulated fork designed for use in the rear axle steering of a motor vehicle.

[0014] Fig. 2 shows the joint fork in top view,

[0015] Fig. 3 shows the joint fork in side view,

[0016] Fig. 4 shows a base body of the joint fork and a central screw inserted into the base body,

[0017] Fig. 5 shows the joint fork in perspective view.

[0018] A joint fork, designated in its entirety by reference numeral 1, is intended for use in a rear axle steering system 10 of a motor vehicle (not shown). The joint fork 1 comprises a base body 2, which is rigidly connected to a U-shaped sheet metal connector 13.

[0019] The two U-shaped legs of the sheet metal connector 13, which describe a fork shape, are designated as cheeks 8 and 9. A central axis MA of the base body 2 coincides with the longitudinal axis of a central screw 7, which is inserted through a central opening 6 in the base body 2 and screwed into a push rod (not shown) of an actuator of the rear axle steering 10 in order to attach the base body 2 to the push rod. The screw head of the central screw 7, which rests against contours of the base body 2, is designated 15.

[0020] The base body 2 forms two parallel flat sections 3 and 4, which, without loss of generality, are designated as the upper flat section 3 and the lower flat section 4, respectively. The U-shaped sheet metal connector 13 engages between these flat sections. The flat sections 3 and 4 of the base body 2 lie in planes between which the central axis MA is located. Furthermore, the base body 2 has a ring section 5 facing the push rod. A plane adjacent to the ring section 5 is designated as the reference plane BE. The central axis MA represents a surface normal to the reference plane BE.

[0021] The U-shaped sheet metal connector 13 is rigidly attached to the base body 2 by means of two pins 11, 12. The U-base, designated 14, which connects the two U-legs 8, 9, is positioned without play between the upper flat piece 3 and the lower flat piece 4. A plane adjacent to the U-base 14 and simultaneously tangent to the base body 2 is designated as the connection plane AE and forms an angle α with the reference plane BE, which in the exemplary embodiment lies in the range of 12 to 24 degrees.

[0022] The pins 11, 12 are attached to the base body 14 by press fits in bores 20 located in the flat pieces 3, 4. Recesses 16 are visible in the flat pieces 3, 4, centrally located between the lateral areas of the flat pieces 3, 4 in which the bores 20 are located.

[0023] The central axes of the pins 11, 12, each having a circular cross-section and designated An, A12, lie in a plane parallel to the connection plane AE. The radius of each pin 11, 12, designated R and shown in Fig. 1, corresponds to the radius of curvature of the U-shaped sheet metal connector 13, which is located at the transition between one of the U-legs 8, 9 and the U-base 14.

[0024] In both cheeks 8, 9 of the U-shaped sheet metal connector 13 are an elongated hole 18, 19. A connecting part of the rear axle steering 10, which engages between the cheeks 8, 9, is designated 17. An axis passing centrally through the two elongated holes is designated as the reference axis BA. The reference axis BA, as well as the connection plane AE, is inclined relative to the reference plane BE by an angle α. Accordingly, the connecting part 17 is also inclined relative to the pushrod (not shown) by the same angle α.

[0025] In the exemplary embodiment, the entire U-shaped sheet metal connector 13 has a uniform wall thickness d. By fastening the U-shaped sheet metal connector 13 with the pins 11, 12, together with the shape of the base body 2, any displacement of the U-shaped sheet metal connector 13 relative to the base body 2 is prevented. (List of reference symbols)

[0026] 1 joint fork

[0027] 2 basic shapes

[0028] 3 upper flat piece

[0029] 4 lower flat piece

[0030] 5 ring section

[0031] 6 Opening

[0032] 7 Central screw

[0033] 8 Cheek, U-thigh

[0034] 9 Cheek, U-thigh

[0035] 10 Rear axle steering

[0036] 11 pen

[0037] 12 pens

[0038] 13 Sheet metal connector

[0039] 14 U-base

[0040] 15 screw heads

[0041] 16 Exclusion

[0042] 17 Connection part

[0043] 18 elongated holes

[0044] 19 elongated holes

[0045] 20 bore

[0046] a angle

[0047] On the central axis of the pin 11

[0048] A12 Central axis of the pin 12

[0049] AE connection level

[0050] BA reference axis

[0051] d wall thickness

[0052] MA Central Axis

[0053] R radius

Claims

Patent claims 1. Articulated fork (1 ) for a rear axle steering system of a motor vehicle, with an asymmetrically designed base body (2) which has an opening (6) for inserting a central screw (7) oriented perpendicular to a reference plane (BE) of the base body (2), wherein a connecting plane (AE) of the base body (2) inclined to the reference plane (BE) is parallel to the central axes (A11 , A12) of two pins (11, 12) inserted into the base body (2), and wherein a U-shaped sheet metal connecting piece (13), the legs (8, 9) of which are designed as parallel cheeks having aligned openings (18, 19), is supported on the base body (2) by a U-base (14) connecting the legs (8, 9) to each other and which is tangent to the connecting plane (AE), wherein at the same time the two pins (11 , 12), which are each located at the transition between the U-base (14) and one of the U-legs (8, 9),block any displacement of the sheet metal connecting piece (13) along a reference axis (BA) placed centrally through the aforementioned openings (18, 19).

2. Joint fork (1 ) according to claim 1 , characterized in that the radius of curvature (R) on the inside of the U-shaped sheet metal connector (13) in the transition area between the U-base (14) and the U-leg (8, 9) corresponds to the radius of the pin (11, 12).

3. Articulated fork (1) according to claim 1 or 2, characterized in that the sheet metal connecting piece (13) has a uniform wall thickness (d).

4. Joint fork (1) according to claim 3, characterized in that the diameter (2 ■ R) of the pin (11, 12) is larger than the wall thickness (d) of the sheet metal connecting piece (13).

5. Joint fork (1) according to one of claims 1 to 4, characterized in that the two U-shaped legs (8, 9) are of equal length.

6. Joint fork (1) according to one of claims 1 to 5, characterized in that the pins (11, 12) are pressed into the base body (2).

7. Articulated fork (1) according to claim 6, characterized in that those areas of the base body (2) designed as flat pieces (3, 4), into which the pins (11, 12) are pressed in, blocking displacements of the sheet metal connector (13) in the longitudinal direction of the pins (11, 12).

8. Rear axle steering (10) comprising at least one articulated fork (1) according to claim 1.

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