CN216943251U

CN216943251U - Steering intermediate shaft device for vehicle steering system

Info

Publication number: CN216943251U
Application number: CN202220750554.3U
Authority: CN
Inventors: 邱碧松; 樊华
Original assignee: Volvo Car Corp
Current assignee: Volvo Car Corp
Priority date: 2022-03-31
Filing date: 2022-03-31
Publication date: 2022-07-12
Anticipated expiration: 2032-03-31

Abstract

The present invention relates to a steering intermediate shaft device for a vehicle steering system, comprising: the steering intermediate shaft is characterized in that one axial end of the steering intermediate shaft comprises an assembly area; a first gimbal comprising an outer sleeve; and a hydraulic bushing including an inner tube, an outer tube, and an elastic element circumferentially disposed between the inner tube and the outer tube to be fixedly connected with the inner tube and the outer tube, the elastic element forming a hydraulic chamber in which the non-Newtonian fluid is enclosed; wherein the hydraulic bushing is at least partially circumferentially disposed between the fitting region and the outer sleeve such that the fitting region is interference fit in the inner tube of the hydraulic bushing and the outer tube of the hydraulic bushing is interference fit in the outer sleeve, thereby securing the first universal joint to the axial one end of the steer axle. The steering intermediate shaft device for the vehicle steering system can transmit higher torque, has high response characteristic and reliability, and has excellent NVH performance.

Description

Steering intermediate shaft device for vehicle steering system

Technical Field

The present invention relates to the technical field of vehicle steering systems, and more particularly, to a steering intermediate shaft device for a vehicle steering system.

Background

When a driver turns the steering wheel, the torque from the steering wheel is amplified and transmitted to wheel shafts of wheels through the steering column, the steering intermediate shaft device, the steering machine and the like in sequence, so that the wheels are steered. However, high or low frequency vibrations caused by excitation of the wheels by rough road surfaces or other factors are also transmitted to the steering wheel via the suspension system connected to the wheels, the subframe or frame connected to the suspension system, and the steering gear mounted to the subframe or frame and back again, which seriously affect NVH (noise, vibration, and harshness) performance inside the vehicle.

SUMMERY OF THE UTILITY MODEL

An object of the present invention is to provide a steering intermediate shaft device for a vehicle steering system, so that the vehicle steering system can transmit higher torque, has high response characteristics, high reliability, and at the same time has excellent NVH performance.

According to an aspect of the present invention, there is provided a steering intermediate shaft device for a vehicle steering system, including: the steering intermediate shaft is characterized in that one axial end of the steering intermediate shaft comprises an assembly area; a first gimbal comprising an outer sleeve; and a hydraulic bushing including an inner tube, an outer tube, and an elastic element circumferentially disposed between the inner tube and the outer tube to be fixedly connected with the inner tube and the outer tube, the elastic element forming a hydraulic chamber in which a non-Newtonian fluid is enclosed; wherein the hydraulic bushing is at least partially circumferentially disposed between the fitting region and the outer sleeve such that the fitting region is interference fit in the inner tube of the hydraulic bushing and the outer tube of the hydraulic bushing is interference fit in the outer sleeve, thereby securing the first universal joint to the axial one end of the steer axle.

Optionally, the steering intermediate shaft device for a vehicle steering system further includes a second universal joint fixed to the other end of the steering intermediate shaft, the steering intermediate shaft being configured to be connected to one of the steering column and the steering engine by means of the first universal joint and to the other of the steering column and the steering engine by means of the second universal joint to transmit torque from the steering column to the steering engine.

Optionally, the hydraulic chamber includes a first chamber, a second chamber, and a fluid passage communicating the first chamber with the second chamber, and the non-newtonian fluid is configured to be held in the first chamber and the second chamber in a state where the steering intermediate shaft transmits the torque from the steering column to the steering machine, and to flow between the first chamber and the second chamber via the fluid passage in a state where the vibration from the steering machine is transmitted to the hydraulic bushing.

Optionally, the fluid channel is shaped to prevent flow of the non-newtonian fluid between the first chamber and the second chamber via the fluid channel in a state where a viscosity of the non-newtonian fluid reaches a preset value.

Optionally, the axial end of the steering intermediate shaft comprises a connection region located in the outer sleeve directly adjacent to the fitting region, and the steering intermediate shaft arrangement further comprises a failsafe mechanism configured to connect the connection region to the outer sleeve to enable torque to be transmitted between the steering intermediate shaft and the first universal joint also in the event of failure of the hydraulic bushing.

Optionally, the fail-safe mechanism comprises a loose interface formed on the connection region and a connector secured to the outer sleeve, the connector being inserted into the loose interface with a clearance fit.

Alternatively, the connecting region is closer to the other end of the steering intermediate shaft than the fitting region, and the diameter of the connecting region is larger than that of the fitting region.

Alternatively, the fitting region is closer to the other end of the steering intermediate shaft than the connection region, and the diameter of the connection region is equal to the diameter of the fitting region.

Optionally, the fail-safe mechanism comprises a loose interface formed on the outer sleeve and a connector secured to the connection region, the connector being inserted into the loose interface with a clearance fit.

Optionally, the first gimbal is configured as a cross-type gimbal and the first gimbal comprises a yoke integrally formed with the outer sleeve.

The steering intermediate shaft device for the vehicle steering system provided by the utility model has the advantages that the hydraulic bushing sealed with the non-Newtonian fluid is configured, so that the steering intermediate shaft device can show high response characteristics when the torque from the steering column is transmitted to the steering engine, and can also show vibration damping performance in a state that the vibration of the steering engine is transmitted to the hydraulic bushing, and the NVH performance of the vehicle is improved. Moreover, the steering intermediate shaft device for the vehicle steering system provided by the utility model prevents potential safety hazards caused by possible failure of the hydraulic bushing by configuring a failure protection mechanism.

Other features of the present invention and advantages thereof will become apparent from the following detailed description of exemplary embodiments thereof, which proceeds with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the utility model and together with the description, serve to explain the principles of the utility model.

Fig. 1 is a perspective view of a steered intermediate shaft device for a vehicle steering system according to one embodiment of the present invention.

Fig. 2 is a perspective view of a steered intermediate shaft device for a vehicle steering system according to another embodiment of the present invention.

Fig. 3 is a sectional view of a steering intermediate shaft device for a vehicle steering system of fig. 1.

Fig. 4 is a sectional view of a steering intermediate shaft device for a vehicle steering system according to still another embodiment of the present invention.

Detailed Description

Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that: the relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise.

Techniques and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail, but are intended to be considered a part of the specification where appropriate.

In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

The vehicle steering system mentioned herein may be used for various vehicles including fuel-powered vehicles, hybrid vehicles, and pure electric vehicles, etc. As is well known, a vehicle steering system basically includes a steering wheel, a steering column, a steering intermediate shaft device, a steering gear, etc., wherein the steering wheel is first connected to the steering column to operatively transmit a torque representative of a steering request to the steering column; the steering column is in turn connected to an intermediate steering shaft for further steering downward torque transfer by the intermediate steering shaft relative to the vertical direction of the vehicle; the intermediate steering shaft is in turn connected to a steering gear to amplify the torque by the steering gear, which amplified torque will be used to effect wheel steering.

Referring to fig. 1, the steering intermediate shaft device may include a steering intermediate shaft 12, a first universal joint 14 fixed to one axial end of the steering intermediate shaft 12, and a second universal joint 16 fixed to the other axial end of the steering intermediate shaft 12, wherein the steering intermediate shaft 12 is connected to one of a steering column and a steering machine (not shown) by means of the first universal joint 14, and is connected to the other of the steering column and the steering machine by means of the second universal joint 16, to transmit torque from the steering column to the steering machine. In the following, the example will be described in which the intermediate steering shaft 12 is connected to the steering machine by means of a first universal joint 14 and to the steering column by means of a second universal joint 16, but it will be understood that it is also entirely feasible for the intermediate steering shaft 12 to be connected to the steering column by means of the first universal joint 14 and to the steering machine by means of the second universal joint 16 without detracting from the function of the intermediate steering shaft arrangement provided by the utility model.

The steering intermediate shaft 12 may include a sleeve 12a formed with internal splines and a core 12b formed with external splines, whereby the sleeve 12a and the core 12b may be connected together by a form fit of the internal and external splines, requiring that the core 12b be axially movable relative to the sleeve 12a to satisfy four-way adjustment of the steering column and to provide sufficient crush distance in the event of a vehicle collision or other emergency. Therefore, for ease of understanding, the axial one end of the steering intermediate shaft 12 described below with reference to fig. 1 and 3 may be the axial one end of the shaft sleeve 12a remote from the shaft core 12b, and the axial other end of the steering intermediate shaft 12 may be the axial one end of the shaft core 12b remote from the shaft sleeve 12a, and it is also possible that the axial one end and the axial other end of the steering intermediate shaft 12 are arranged oppositely.

With continued reference to fig. 1, the first universal joint 14 of the steer intermediate shaft assembly may be a cross-type universal joint, and generally includes a first yoke 18 for securing to an axial end of the steer intermediate shaft 12, a first cross 20 (as shown in fig. 2), and a second yoke 22 for securing to an input shaft of a steering engine, including but not limited to rack and pinion steering engines, worm crank pin steering engines, ball screw steering engines, and the like, which may receive torque from the second yoke 22 to amplify the received torque using internal mechanisms of the steering engine. The first cross 20 includes a first shaft 20a and a second shaft 20b, a first axis of the first shaft 20a and a second axis of the second shaft 20b cross each other perpendicularly, the first yoke 18 is rotatably connected to both axial ends of the first shaft 20a with respect to the first axis, and the second yoke 22 is rotatably connected to both axial ends of the second shaft 20b with respect to the second axis.

The second universal joint 16 is similar to the first universal joint 14, that is, the second universal joint 16 mainly includes a third yoke 15 for fixing to the axially other end of the steering intermediate shaft 12, a second cross shaft, and a fourth yoke 17 for fixing to the output shaft of the steering column, and the fourth yoke 17 can receive torque from the output shaft of the steering column to further transmit the received torque to the steering intermediate shaft 12.

It is to be understood that the arrangement of the first and second

universal joints

14 and 16 is not limited as long as the first and second

universal joints

14 and 16 can be used to change the transmission direction or the transmission angle of the torque.

The first gimbal 14 differs from the second gimbal 16 in that the first gimbal 14 additionally includes an outer sleeve 24, and the outer sleeve 24 may be formed integrally with the first yoke 18 or the outer sleeve 24 may be formed separately and then assembled to the first yoke 18. For example, the first yoke 18 may protrude from a circumferential edge of the outer sleeve 24 in a direction parallel to an axis of the outer sleeve 24.

Referring to fig. 3, the steer intermediate axle assembly further includes a hydraulic bushing 26, the hydraulic bushing 26 including an inner tube 28, e.g., made of metal, an outer tube 30, e.g., made of metal, and a resilient member 32 disposed circumferentially between the inner and

outer tubes

28, 30 to secure the inner and

outer tubes

28, 30 together, e.g., the resilient member 32 is at least partially made of rubber.

In order to fit the hydraulic bushing 26 to the steering intermediate shaft 12 and the first universal joint 14, the axial end of the steering intermediate shaft 12 may comprise a fitting region 34, the hydraulic bushing 26 in turn being arranged at least partially circumferentially between the fitting region 34 and the outer sleeve 24, such that the fitting region 34 is interference-fitted in the inner tube 28 of the hydraulic bushing 26 and the outer tube 30 of the hydraulic bushing 26 is interference-fitted in the outer sleeve 24, thereby fixing the first universal joint 14 to the axial end of the steering intermediate shaft 12, in which case the axis of the steering intermediate shaft 12, the axis of the hydraulic bushing 26 and the axis of the outer sleeve 24 are arranged coaxially with one another. In other words, during assembly of the hydraulic bushing 26, the inner tube 28 and the outer tube 30 of the hydraulic bushing 26 will be slightly deformed so that the hydraulic bushing 26 is tightly fitted to the steer intermediate shaft 12 and the first universal joint 14, thereby ensuring efficient torque transmission between the steer intermediate shaft 12 and the first universal joint 14.

The resilient member 32 is formed with a hydraulic chamber to enclose the non-newtonian fluid therein. For example, the resilient member 32 may be split from a plurality of sections to collectively define a hydraulic chamber from the plurality of sections. Alternatively, the resilient element 32 is integrally formed to form a hydraulic chamber in the resilient element 32. In particular, a non-Newtonian fluid is a fluid that does not satisfy the Newtonian law of viscosity or for which the viscosity is not constant. Preferably, the viscosity of the non-newtonian fluid used in the present invention increases with increasing shear stress or shear rate, i.e., when the non-newtonian fluid is subjected to a strong impact of an external force and needs to be shear-deformed, the intermolecular connecting force of the non-newtonian fluid is caused to increase, so that the viscosity of the non-newtonian fluid increases even to have a solid property, and the non-newtonian fluid reversibly restores the property of the low viscosity fluid after the strong impact of the external force becomes small or ends. For example, such a non-Newtonian fluid may be the D3O material that is commercially available.

The hydraulic chamber includes a first chamber 36, a second chamber 38, and a fluid passage 40 communicating the first chamber 36 with the second chamber 38, the fluid passage 40 having a cross section and a volume smaller than those of either one of the first chamber 36 and the second chamber 38 to have a throttling action, and the non-newtonian fluid is mainly contained in the first chamber 36 and the second chamber 38. When high or low frequency vibrations resulting from excitation of the wheels by rough terrain or other factors are transmitted to the steer mid-axle assembly via the suspension system connected to the wheels, the subframe or frame connected to the suspension system, and the steering gear mounted to the subframe or frame, the forces generated by the high or low frequency vibrations may compress one of the first and

second chambers

36, 38 of the hydraulic bushing 26, but because of the lower forces, the non-newtonian fluid will retain the characteristics of the low viscosity fluid and therefore flow along the fluid passage 40 to the other of the first and

second chambers

36, 38. The flow of the non-Newtonian fluid in fluid passage 40 enables hydraulic bushing 26 to have a high damping hysteresis at a particular frequency, thereby providing a damping effect to the vehicle steering system. When torque from the steering wheel, particularly a fast large torque in an emergency situation, is transmitted through the steering column to the steer countershaft assembly, the viscosity of the non-newtonian fluid in the hydraulic bushing 26 of the steer countershaft assembly rapidly increases due to the strong impact of the torque, such that the non-newtonian fluid flows dilatantly in the first and

second chambers

36, 38, and is even held captive in the first and

second chambers

36, 38 and is substantially unable to flow, while the increased viscosity of the non-newtonian fluid may provide support to the resilient member 32 such that the hydraulic bushing 26, and thus the steer countershaft assembly, is rigidly responsive to the torque from the steering column.

Alternatively, the fluid passage 40 may be shaped to substantially or completely prevent the flow of the non-newtonian fluid between the first and

second chambers

36, 38 via the fluid passage 40 in a state where the viscosity of the non-newtonian fluid reaches a preset value, to adjust timing at which the hydraulic bushing 26 is expected to be rigidly responsive to an external force shock, i.e., so that the hydraulic bushing 26 exhibits high response characteristics in a state where torque from the steering column is transmitted to the steering machine, and exhibits vibration damping performance in a state where vibration from the steering machine is transmitted to the hydraulic bushing 26.

Optionally, the steering countershaft assembly further includes a failsafe mechanism, and the axial end of the steering countershaft 12 includes a connection region 46 located in the outer sleeve 24 directly adjacent the mounting region 34, the failsafe mechanism connecting the connection region 46 to the outer sleeve 24 to enable torque transfer between the steering countershaft 12 and the first universal joint 14 also in the event of a failure of the hydraulic bushing 26.

For example, referring to fig. 1 and 3 in combination, the fail-safe mechanism may include a loose interface 42 formed on the outer sleeve 24 and a connector 44 secured to the connection region 46, the connector 44 extending radially outward from the connection region 46 perpendicular to the axis of the steer axle 12 to be inserted into the loose interface 42 with a clearance fit, i.e., the portion of the connector 44 that engages the loose interface 42 has a circular cross-section or a non-circular cross-section, the loose interface 42 has an axial width parallel to the axis of the outer sleeve 24 and a circumferential length perpendicular to the axis of the outer sleeve 24, and both the axial width and the circumferential length of the loose interface 42 are greater than the diameter of the circular cross-section of the connector 44 or the corresponding side of the non-circular cross-section of the connector 44. In this case, when the hydraulic bushing 26 is not failed, since the first gimbal 14 is fixed to the axial end of the intermediate steering shaft 12 by means of the hydraulic bushing 26, and the connecting member 44 is not yet in contact with the outer sleeve 24 in practice, the torque from the steering column will be transmitted between the intermediate steering shaft 12 and the first gimbal 14 only through the hydraulic bushing 26. When the hydraulic bushing 26 fails, the torque from the steering column will cause the axial end of the steer axle 12 to rotate relative to the first universal joint 14 until the connector 44 reaches the end of the circumferential length of the loose interface 42 to contact the outer sleeve 24 so that the torque from the steering column can be transmitted through the fail-safe mechanism to the first universal joint 14, thereby preventing an accident due to the failure of the hydraulic bushing 26.

Alternatively, referring again to fig. 2 with the outer sleeve 24 removed, the fail-safe mechanism may include a loose interface 42 'formed on the connection region 46 and a connector 44' secured to the outer sleeve 24, the connector 44 'extending radially inward from the outer sleeve 24 perpendicular to the axis of the outer sleeve 24 for clearance fit insertion into the loose interface 42'. Similarly, when hydraulic bushing 26 is not deactivated, link 44' is not yet in contact with connection region 46, and torque from the steering column is transmitted between intermediate steering shaft 12 and first universal joint 14 only through hydraulic bushing 26; when the hydraulic bushing 26 fails, torque from the steering column will cause the axial end of the steer axle 12 to rotate relative to the first universal joint 14 until the connection 44 'reaches an end of the circumferential length of the loose interface 42' to contact the connection region 46 so that torque from the steering column can be transmitted through the fail-safe mechanism to the first universal joint 14.

The loose interfaces 42, 42 'may be configured, on the one hand, as kidney-shaped openings that extend radially through the outer sleeve 24 or the connection region 46, and on the other hand, the connectors 44, 44' may be configured as one-piece studs, bolts, or bolt assemblies, etc. that pass through the kidney-shaped openings. It will be appreciated that the arrangement of the loose interfaces 42, 42 'and connectors 44, 44' is not limited, as long as the engagement of the loose interfaces 42, 42 'and connectors 44, 44' can function as a fail safe.

The diameter of one axial end of the steering intermediate shaft 12, in particular of the fitting region 34 of the steering intermediate shaft 12, is reduced relative to the diameter of the remaining region of the steering intermediate shaft 12 to form a compact arrangement, in the embodiment of fig. 1 to 3 the fitting region 34 being closer to the other axial end of the steering intermediate shaft 12 than the connection region 46, and the diameter of the fitting region 34 being the same as the diameter of the connection region 46. Alternatively, referring to fig. 4, particularly in the case of providing a loose joint, particularly a kidney-shaped opening, on the connection region, in order to ensure the structural strength of the connection region, a connection region 46 ' may be provided which is closer to the axially other end of the steering intermediate shaft 12 than the fitting region 34, and therefore the hydraulic bushing 26 is arranged entirely circumferentially between the fitting region 34 and the outer sleeve 24, and in this case the diameter of the connection region 46 ' is greater than that of the fitting region 34, i.e., the axially one end of the steering intermediate shaft 12 is not yet reduced at the connection region 46 '. In addition, the configuration of the connection region 46' does not affect or take up the desired distance that the core 12b can axially collapse relative to the sleeve 12 a.

Although some specific embodiments of the present invention have been described in detail by way of illustration, it should be understood by those skilled in the art that the above illustration is only for the purpose of illustration and is not intended to limit the scope of the utility model. It will be appreciated by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the utility model. The scope of the utility model is defined by the appended claims.

Claims

1. A steering intermediate shaft device for a vehicle steering system, characterized by comprising:

a steering intermediate shaft (12), one axial end of the steering intermediate shaft (12) comprising a fitting region (34);

a first gimbal (14), the first gimbal (14) including an outer sleeve (24); and

a hydraulic bushing (26), the hydraulic bushing (26) including an inner tube (28), an outer tube (30), and an elastic element (32) disposed circumferentially between the inner tube (28) and the outer tube (30) to be fixedly attached to the inner tube (28) and the outer tube (30), the elastic element (32) forming a hydraulic chamber within which a non-Newtonian fluid is enclosed;

wherein the hydraulic bushing (26) is at least partially circumferentially arranged between the fitting region (34) and the outer sleeve (24) such that the fitting region (34) is interference fitted in the inner tube (28) of the hydraulic bushing (26) and the outer tube (30) of the hydraulic bushing (26) is interference fitted in the outer sleeve (24), thereby fixing the first universal joint (14) to the axial one end of the steer-countershaft (12).

2. The steering intermediate shaft device for a vehicle steering system according to claim 1, further comprising a second universal joint (16) fixed to the other end of the steering intermediate shaft (12), the steering intermediate shaft (12) being configured to be connected to one of the steering column and the steering engine by means of the first universal joint (14) and to the other of the steering column and the steering engine by means of the second universal joint (16) to transmit torque from the steering column to the steering engine.

3. The steering intermediate shaft device for a vehicle steering system according to claim 2, wherein the hydraulic chamber includes a first chamber (36), a second chamber (38), and a fluid passage (40) communicating the first chamber (36) with the second chamber (38), the non-newtonian fluid is configured to be held staying in the first chamber (36) and the second chamber (38) in a state where the steering intermediate shaft (12) transmits torque from the steering column to the steering machine, and to flow between the first chamber (36) and the second chamber (38) via the fluid passage (40) in a state where vibration from the steering machine is transmitted to the hydraulic bushing (26).

4. The steering countershaft apparatus for a vehicle steering system according to claim 3, wherein the fluid passage (40) is shaped to prevent the non-Newtonian fluid from flowing between the first chamber (36) and the second chamber (38) through the fluid passage (40) in a state where a viscosity of the non-Newtonian fluid reaches a preset value.

5. The steering intermediate shaft device for a vehicle steering system according to any one of claims 1 to 4, characterized in that an axial end of the steering intermediate shaft (12) includes a connection region located in the outer sleeve (24) directly adjacent to the fitting region (34), and the steering intermediate shaft device further includes a fail-safe mechanism configured to connect the connection region to the outer sleeve (24) so that torque can be transmitted between the steering intermediate shaft (12) and the first universal joint (14) also in a state where the hydraulic bushing (26) fails.

6. The steering intermediate shaft device for a vehicle steering system according to claim 5, wherein the fail-safe mechanism includes a loose joint formed on the connecting region and a connecting member fixed to the outer sleeve (24), the connecting member being inserted into the loose joint with a clearance fit.

7. The steering intermediate shaft device for a vehicle steering system according to claim 6, characterized in that the connecting region is closer to the other end of the steering intermediate shaft (12) than the fitting region (34), and the diameter of the connecting region is larger than that of the fitting region (34).

8. The steering intermediate shaft device for a vehicle steering system according to claim 6, wherein the fitting region (34) is located closer to the other end of the steering intermediate shaft (12) than the connection region, and the diameter of the connection region is equal to the diameter of the fitting region (34).

9. The steering intermediate shaft device for a vehicle steering system according to claim 5, wherein the fail-safe mechanism includes a loose joint formed on the outer sleeve (24) and a connecting member fixed to the connecting region, the connecting member being inserted into the loose joint with a clearance fit.

10. The steer intermediate shaft assembly for a vehicle steering system according to any one of claims 1 to 4, wherein the first universal joint (14) is configured as a cross-type universal joint, and the first universal joint (14) includes a yoke (18) integrally formed with the outer sleeve (24).