Steering gear for a steering system of a motor vehicle, and production method

Abstract

The invention relates to a steering gear (10) for a steering system of a motor vehicle, comprising a housing (12) of the servo unit (14), said housing (12) having a circular opening (16), wherein a plurality of first radial projections (18) arranged at a distance from one another in the circumferential direction are formed on the circumferential surface (16a) of the opening (16); and comprising a servo cover (20). A plurality of latching elements (22) arranged at a distance from one another in the circumferential direction are formed on a circumferential surface of the servo cover (20) and are designed to interact, in a closed position of the bayonet closure, with the first radial projections (18) formed on the circumferential surface (16a) of the opening (16) of the housing (12) of the servo unit (14) in such a way that the servo cover (20) is rotationally fixed in the opening (16) of the housing (12) of the servo unit (14). The invention further relates to a method for producing a bayonet closure for a steering gear (10) of a steering system for a motor vehicle.

Description

[0001] Description

[0002] title

[0003] Steering gear for a one and ren

[0004] The invention relates to a steering gear for a steering system of a motor vehicle.

[0005] Furthermore, the invention provides a method for producing a bayonet lock for a steering gear of a steering system for a motor vehicle.

[0006] State of the art

[0007] EP 0241691 A2 discloses a rack and pinion steering system, in particular for motor vehicles, with a rack arranged axially displaceably in a steering gear housing and with a pinion driven by the steering wheel, mounted in the steering gear housing and actuating the rack.

[0008] In a rack and pinion steering system, the rotational movement from the steering wheel is transferred to the rack via a pinion and translated into a translational movement of the rack, which is transmitted to the wheel to be steered via a tie rod and other vehicle parts.

[0009] Housing components in steering gears are typically connected by positive locking, e.g., using screws or snap hooks with undercuts. The interface between the housing components is sealed either using conventional solid seals such as O-rings, molded seals, or by applying liquid sealant.

[0010] However, positive-locking connections or liquid sealants require additional components as well as a specific design of the components, such as screw joints, which require installation space and are reflected in the material and manufacturing costs.

[0011] O-rings require additional installation space. These are critically evaluated with regard to crevice corrosion. The application of liquid sealant can only be performed within the steering assembly and places high demands on process control and monitoring.

[0012] The object of the invention is therefore to provide an improved steering gear which enables simplified, more efficient and more cost-effective assembly and manufacture of housing covers of the steering gear of motor vehicles without compromising on the requirements specifically regarding corrosion resistance at the interfaces.

[0013] The object is achieved by a steering gear for a steering system of a motor vehicle having the features of patent claim 1.

[0014] Furthermore, the object is achieved by a method for producing a bayonet lock for a steering gear of a steering system for a motor vehicle with the features of patent claim 11.

[0015] Disclosure of the invention

[0016] The present invention provides a steering gear for a steering system of a motor vehicle

[0017] The steering gear comprises a housing of the servo unit, which housing has a circular opening, wherein a plurality of first radial projections arranged spaced apart from one another in the circumferential direction are formed on a circumferential surface of the opening.

[0018] Furthermore, the steering gear comprises a servo cover, wherein a plurality of locking elements arranged spaced apart from one another in the circumferential direction are formed on a circumferential surface of the servo cover, which locking elements form a bayonet closure in conjunction with the first radial projections of the housing of the servo unit, wherein the locking elements are designed to cooperate, in a closed position of the bayonet closure, with the first radial projections formed on the circumferential surface of the opening of the housing of the servo unit such that the servo cover is fixed in a rotationally fixed manner in the opening of the housing of the servo unit.

[0019] The present invention further provides a method for producing a bayonet lock for a steering gear of a steering system for a motor vehicle.

[0020] The method comprises providing a housing of the servo unit, which housing has a circular opening, and providing a servo cover insertable into the circular opening of the housing of the servo unit.

[0021] Furthermore, the method comprises milling a contour formed on a circumferential surface of the opening of the housing of the servo unit, wherein the contour has a plurality of first radial projections arranged spaced apart from one another in the circumferential direction, wherein a milling operation is carried out using a single milling tool which is moved along a predetermined path.

[0022] One idea of ​​the present invention is to achieve a smaller package compared to a classic snap-in hook solution. This also results in a cost advantage, as the cover is made of a single material and functions without the need for additional inserts. Furthermore, the aim of the invention is to fix the cover in the housing with axial, rotational, and positional precision, and to provide a defined sealing contour for a silicone gasket.

[0023] Advantageous embodiments and further developments emerge from the subclaims and from the description with reference to the figures.

[0024] According to a preferred development, it is provided that the plurality of locking elements of the servo cover each have a second projection formed in the circumferential direction of the servo cover, which is at least partially wedge-shaped or arcuate and which, in the closed position of the bayonet lock, is plastically deformable by the respective first radial projection of the housing of the servo unit.

[0025] This advantageously ensures that the servo cover is securely fixed in the housing of the servo unit.

[0026] According to a further preferred development, it is provided that the plurality of locking elements of the servo cover each have a third projection formed in the circumferential direction of the servo cover and which is at least partially wedge-shaped or arcuate, wherein the at least partially wedge-shaped or arcuate third projection has a toothing which can be locked to the respective first radial projection of the housing of the servo unit.

[0027] This advantageously enables a step-by-step locking of the servo cover in the housing of the servo unit.

[0028] According to a further preferred development, it is provided that the plurality of locking elements of the servo cover each have a bending beam formed in the circumferential direction of the servo cover, wherein the bending beam has a fourth radial projection and a fifth radial projection, wherein a notch for receiving the first radial projection of the housing of the servo unit is formed between the fourth radial projection and the fifth radial projection.

[0029] The notch thus allows the servo cover to be positioned precisely relative to the housing of the servo unit.

[0030] According to a further preferred development, the fourth radial projection and the fifth radial projection of the bending beam are elastically deformable for inserting the first radial projection of the servo unit housing into the notch of the bending beam. The bending beam thus enables a defined locking of the servo cover with a predetermined torque in the servo unit housing.

[0031] According to a further preferred development, it is provided that the plurality of locking elements of the servo cover each have a bending hook formed in the circumferential direction of the servo cover, wherein the bending hook has a web extending substantially radially from a surface of the servo cover and a hook-shaped section formed on an end section of the web substantially in the circumferential direction of the servo cover.

[0032] The hook-shaped section thus advantageously has a predetermined radial distance from a surface of the servo cover.

[0033] According to a further preferred development, it is provided that the hook-shaped section of the bending hook is designed to be movable over at least one of the first radial projections in a first direction of rotation when the servo cover is screwed into the circular opening of the housing, and wherein the hook-shaped section of the bending hook is blockable in a second direction of rotation opposite to the first direction of rotation by a respective first radial projection.

[0034] The hook-shaped section is thus designed to provide radial securing of the servo cover in the circular opening of the housing.

[0035] According to a further preferred development, it is provided that the servo cover has a plurality of fixing elements arranged along the circumferential surface of the servo cover, wherein the fixing elements are designed to be brought into engagement with undercuts arranged along the circumferential surface of the opening of the housing of the servo unit.

[0036] The fixing elements thus enable axial securing of the servo cover in the circular opening of the housing. According to a further preferred development, a silicone seal is applied to the inside of the servo cover. This results in increased sealing performance.

[0037] According to a further preferred development, an axial sixth projection having a predetermined n-edged geometry is formed on an outer side of the servo cover, and the housing of the servo unit has a plurality of insertion grooves for axially inserting the servo cover into the circular opening of the housing of the servo unit. The n-edged geometry enables the servo cover to be easily and securely screwed into the circular opening of the housing using a standardized tool.

[0038] The described designs and further training courses can be combined as desired.

[0039] Further possible embodiments, developments and implementations of the invention also include combinations of features of the invention described previously or below with regard to the embodiments that are not explicitly mentioned.

[0040] Short description of the drawings

[0041] The accompanying drawings are intended to provide a further understanding of embodiments of the invention. They illustrate embodiments and, in conjunction with the description, serve to explain principles and concepts of the invention.

[0042] Other embodiments and many of the aforementioned advantages will become apparent upon review of the drawings. The elements illustrated in the drawings are not necessarily drawn to scale.

[0043] 1 shows a perspective view of a steering gear for a steering system of a motor vehicle according to a preferred embodiment of the invention;

[0044] Fig. 2 is a perspective view of a servo cover of the steering gear for the steering system of the motor vehicle according to a first embodiment of the invention;

[0045] Fig. 3 is a detailed view of a bayonet lock of the steering gear for the steering system of the motor vehicle according to the first embodiment of the invention;

[0046] Fig. 4 is a perspective view of a servo cover of the steering gear for the steering system of the motor vehicle according to a second embodiment of the invention;

[0047] Fig. 5 is a detailed view of a bayonet lock of the steering gear for the steering system of the motor vehicle according to the second embodiment of the invention;

[0048] Fig. 6 is a perspective view of a servo cover of the steering gear for the steering system of the motor vehicle according to a third embodiment of the invention;

[0049] Fig. 7 is a detailed view of a bayonet lock of the steering gear for the steering system of the motor vehicle according to the third embodiment of the invention;

[0050] Fig. 8 is a perspective view of a servo cover of the steering gear for the steering system of the motor vehicle according to a fourth embodiment of the invention;

[0051] Fig. 9 is a detailed view of a bayonet lock of the steering gear for the steering system of the motor vehicle according to the fourth embodiment of the invention; Fig. 10 is a perspective view of the servo cover of the steering gear for the steering system of the motor vehicle according to the first to fourth embodiments of the invention;

[0052] Fig. 11 is a side view of the servo cover of the steering gear for the steering system of the motor vehicle according to the first embodiment of the invention;

[0053] Fig. 12 is an enlarged cross-sectional view of the servo cover of the steering gear for the steering system of the motor vehicle according to the first embodiment of the invention;

[0054] Fig. 13 is an enlarged cross-sectional view of the servo cover of the steering gear for the steering system of the motor vehicle according to the first embodiment of the invention;

[0055] Fig. 14 is a flowchart of a method for manufacturing a bayonet lock for a steering gear of a steering system for a motor vehicle according to the preferred embodiment of the invention; and

[0056] Fig. 15 is a perspective view showing a milling process of a housing of the servo unit of the steering gear for the steering system of the motor vehicle according to the first to fourth embodiments of the invention.

[0057] In the figures of the drawings, the same reference symbols designate the same or functionally equivalent elements, parts or components, unless otherwise stated.

[0058] Fig. 1 shows a steering gear 10 for a steering system of a motor vehicle.

[0059] The steering gear 10 comprises a housing 12 of the servo unit 14, which housing 12 has a circular opening 16. Fig. 2 and Fig. 3 show a perspective view of a servo cover 20a and the bayonet lock of the steering gear 10 for the steering system of the motor vehicle according to a first embodiment of the invention.

[0060] On a circumferential surface 16a of the opening 16, a plurality of first radial projections 18 are formed, arranged spaced apart from one another in the circumferential direction.

[0061] On a circumferential surface of the servo cover 20a, a plurality of locking elements 22 are formed which are arranged spaced apart from one another in the circumferential direction and which, in conjunction with the first radial projections 18 of the housing 12 of the servo unit 14, form a bayonet closure, wherein the locking elements 22 are designed, in a closed position of the bayonet closure, to cooperate with the first radial projections 18 formed on the circumferential surface 16a of the opening 16 of the housing 12 of the servo unit 14 such that the servo cover 20a is fixed in the opening 16 of the housing 12 of the servo unit 14 in a rotationally fixed manner.

[0062] The plurality of locking elements 22 of the servo cover 20a each have a second projection 24 formed in the circumferential direction of the servo cover 20a, which is at least partially wedge-shaped or arcuate and which, in the closed position of the bayonet lock, is plastically deformable by the respective first radial projection 18 of the housing 12 of the servo unit 14.

[0063] Fig. 4 and Fig. 5 show a perspective view of a servo cover 20b and the bayonet closure of the steering gear 10 for the steering system of the motor vehicle according to a second embodiment of the invention.

[0064] The plurality of locking elements 22 of the servo cover 20b each have a third projection 26 formed in the circumferential direction of the servo cover 20b and at least partially wedge-shaped or arcuate. The at least partially wedge-shaped or arcuate third projection 26 further has a toothing 26a, which can be locked to the respective first radial projection 18 of the housing 12 of the servo unit 14.

[0065] Fig. 6 and Fig. 7 show a perspective view of a servo cover 20c and the bayonet lock of the steering gear 10 for the steering system of the motor vehicle according to a third embodiment of the invention;

[0066] The plurality of locking elements 22 of the servo cover 20c each have a bending beam 28 formed in the circumferential direction of the servo cover 20c, wherein the bending beam 28 has a fourth radial projection 30 and a fifth radial projection 32. Between the fourth radial projection 30 and the fifth radial projection 32, a notch 34 is also formed for receiving the first radial projection 18 of the housing 12 of the servo unit 14.

[0067] The fourth radial projection 30 and the fifth radial projection 32 of the bending beam 28 for inserting the first radial projection 18 of the housing 12 of the servo unit 14 are elastically deformable into the notch 34 of the bending beam 28.

[0068] Fig. 8 and Fig. 9 show a perspective view of a servo cover 20d and the bayonet closure of the steering gear 10 for the steering system of the motor vehicle according to a fourth embodiment of the invention.

[0069] The plurality of locking elements 22 of the servo cover 20d further each have a bending hook 36 formed in the circumferential direction of the servo cover 20d. The bending hook 36 has a web 38 extending substantially radially from a surface of the servo cover 20d and a hook-shaped portion 40 formed at an end portion of the web 38 substantially in the circumferential direction of the servo cover 20d. The hook-shaped portion 40 of the bending hook 36 is designed to be moved in a first rotational direction over at least one of the first radial projections when the servo cover 20d is screwed into the circular opening 16 of the housing 12. Furthermore, the hook-shaped portion 40 of the bending hook 36 can be blocked in a second rotational direction opposite to the first rotational direction by a respective first radial projection 18.

[0070] Fig. 10 shows a perspective view of the servo cover 20a-d of the steering gear 10 for the steering system of the motor vehicle according to the first to fourth embodiments of the invention.

[0071] On an outer side of the servo cover 20a-d, an axial sixth projection 46 having a predetermined n-edged geometry is formed.

[0072] Fig. 11 shows a side view of the servo cover 20a of the steering gear 10 for the steering system of the motor vehicle according to the first embodiment of the invention.

[0073] The servo cover 20a further includes a plurality of fixing elements 42 arranged along the circumferential surface of the servo cover 20a. The fixing elements 42 are designed to engage with undercuts arranged along the circumferential surface 16a of the opening 16 of the housing 12 of the servo unit 14. Furthermore, the servo cover 20a includes a centering element 43 for radially positioning the servo cover 20a.

[0074] Fig. 12 shows an enlarged cross-sectional view of the servo cover 20a of the steering gear 10 for the steering system of the motor vehicle according to the first embodiment of the invention.

[0075] A silicone seal 44 is also applied to an inner side of the servo cover 20a. A buffer region 45 is formed adjacent to the silicone seal 44 to compensate for silicone dosage tolerances. Figure 13 shows an enlarged cross-sectional view of the servo cover 20a of the steering gear 10 for the steering system of the motor vehicle according to the first embodiment of the invention.

[0076] The servo cover 20a further has a radial web 52. The radial web 52 ensures maximum rigidity in combination with the thickness of the fixing elements 42. The goal is to achieve minimal deformation in the sealing area, i.e., a balance between the rigidity of the servo cover 20a and the rigidity of the fixing elements 42.

[0077] Fig. 14 shows a flow chart of a method for producing a bayonet lock for a steering gear 10 of a steering system for a motor vehicle according to the preferred embodiment of the invention.

[0078] The method comprises providing S1 a housing 12 of the servo unit 14, which housing 12 has a circular opening 16, and providing S2 a servo cover 20a, 20b, 20c, 20d that can be inserted into the circular opening 16 of the housing 12 of the servo unit 14.

[0079] Furthermore, the method comprises milling S3 of a contour formed on a circumferential surface 16a of the opening 16 of the housing 12 of the servo unit 14, the contour having a plurality of first radial projections 18 arranged spaced apart from one another in the circumferential direction, a milling operation being carried out using a single milling tool 48 which is moved along a predetermined path.

[0080] Fig. 15 shows a perspective view of a milling process of a housing 12 of the servo unit 14 of the steering gear 10 for the steering system of the motor vehicle according to the first to fourth embodiments of the invention.

[0081] The milling process is performed using a single milling tool 48, which is moved along a predetermined path. The housing 12 of the servo unit 14 further includes a plurality of insertion grooves 50 for axially inserting the servo cover 20a, 20b, 20c, 20d into the circular opening 16 of the housing 12 of the servo unit 14.

Claims

Claims 1. Steering gear (10) for a steering system of a motor vehicle, comprising: a housing (12) of the servo unit (14), which housing (12) has a circular opening (16), wherein a plurality of first radial projections (18) arranged spaced apart from one another in the circumferential direction are formed on a circumferential surface (16a) of the opening (16);and a servo cover (20a, 20b, 20c, 20d), wherein a plurality of locking elements (22) arranged spaced apart from one another in the circumferential direction are formed on a circumferential surface of the servo cover (20a, 20b, 20c, 20d), which locking elements (22) form a bayonet closure in conjunction with the first radial projections (18) of the housing (12) of the servo unit (14), wherein the locking elements (22) are designed, in a closed position of the bayonet closure, to cooperate with the first radial projections (18) formed on the circumferential surface (16a) of the opening (16) of the housing (12) of the servo unit (14) in such a way that the servo cover (20a, 20b, 20c, 20d) is fixed in the opening (16) of the housing (12) of the servo unit (14) in a rotationally fixed manner.

2. Steering gear (10) according to claim 1, wherein the plurality of locking elements (22) of the servo cover (20a) each have a second projection (24) formed in the circumferential direction of the servo cover (20a), which is at least partially wedge-shaped or arcuate and which, in the closed position of the bayonet lock, is plastically deformable by the respective first radial projection (18) of the housing (12) of the servo unit (14).

3. Steering gear (10) according to claim 1, wherein the plurality of locking elements (22) of the servo cover (20b) each have a circumferential direction of the servo cover (20b), at least partially wedge-shaped or arcuate third projection (26), wherein the at least partially wedge-shaped or arcuate third projection (26) has a toothing (26a) which can be locked to the respective first radial projection (18) of the housing (12) of the servo unit (14).

4. Steering gear (10) according to claim 1, wherein the plurality of locking elements (22) of the servo cover (20c) each have a bending beam (28) formed in the circumferential direction of the servo cover (20c), wherein the bending beam (28) has a fourth radial projection (30) and a fifth radial projection (32), wherein between the fourth radial projection (30) and the fifth radial projection (32) a notch (34) is formed for receiving the first radial projection (18) of the housing (12) of the servo unit (14).

5. Steering gear (10) according to claim 4, wherein the fourth radial projection (30) and the fifth radial projection (32) of the bending beam (28) are elastically deformable for inserting the first radial projection (18) of the housing (12) of the servo unit (14) into the notch (34) of the bending beam (28).

6. Steering gear (10) according to claim 1, wherein the plurality of locking elements (22) of the servo cover (20d) each have a bending hook (36) formed in the circumferential direction of the servo cover (20d), wherein the bending hook (36) has a web (38) extending substantially radially from a surface of the servo cover (20d) and a hook-shaped section (40) formed on an end section of the web (38) substantially in the circumferential direction of the servo cover (20d).

7. Steering gear (10) according to claim 6, wherein the hook-shaped portion (40) of the bending hook (36) is designed to be movable in a first rotational direction over at least one of the first radial projections when the servo cover (20d) is screwed into the circular opening (16) of the housing (12), and wherein the hook-shaped portion (40) of the bending hook (36) can be blocked in a second direction of rotation opposite to the first direction of rotation by a respective first radial projection (18).

8. Steering gear (10) according to one of the preceding claims, wherein the servo cover (20a) has a plurality of fixing elements (42) arranged along the circumferential surface of the servo cover (20a), wherein the fixing elements (42) are designed to be brought into engagement with undercuts arranged along the circumferential surface (16a) of the opening (16) of the housing (12) of the servo unit (14).

9. Steering gear (10) according to one of the preceding claims, wherein a silicone seal (44) is applied to an inner side of the servo cover (20a).

10. Steering gear (10) according to one of the preceding claims, wherein an axial sixth projection (46) having a predetermined n-edged geometry is formed on an outer side of the servo cover (20a, 20b, 20c, 20d), and wherein the housing (12) of the servo unit (14) has a plurality of insertion grooves (50) for axially inserting the servo cover (20a, 20b, 20c, 20d) into the circular opening (16) of the housing (12) of the servo unit (14).

11. A method for producing a bayonet lock for a steering gear (10) of a steering system for a motor vehicle, comprising the steps: Providing (S1) a housing (12) of the servo unit (14), which housing (12) has a circular opening (16); Providing (S2) a servo cover (20a, 20b, 20c, 20d) insertable into the circular opening (16) of the housing (12) of the servo unit (14); and milling (S3) a contour formed on a circumferential surface (16a) of the opening (16) of the housing (12) of the servo unit (14), wherein the contour has a plurality of first radial projections (18) arranged spaced apart from one another in the circumferential direction, wherein a milling process using a single milling tool (48) which is moved along a predetermined path.

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