Magnetically stabilized cardan shaft bearing system and vehicle equipped with it

Abstract

Magnetically stabilized cardan shaft bearing system (60), comprising: a holder (70) with a bearing receiving zone (82) with an inner annular surface (84); an insulator (90) made of a flexible material, arranged in the bearing receiving zone (82), wherein the insulator (90) has an outer section (92) supported on the inner annular surface (84) and an inner section (94) connected to the outer section (92) via several web elements (96), wherein the inner section (94) includes an opening (98) with an annular surface section (100); a cardan shaft bearing (104) arranged in the bearing receiving zone (82) and supported by the insulator (90), wherein the cardan shaft bearing (104) is arranged in the opening (98) of the inner section (94), the cardan shaft bearing (104) comprising an outer race (106) supported by the annular surface section (100), an inner race (107), and a plurality of bearing elements (109) between the outer race (106) and the inner race (107), wherein the inner race (107) of the cardan shaft bearing (104) includes a passage (112) capable of receiving a cardan shaft (46) for a vehicle rotatably supported; and an electromagnet (120) which is mounted in the holder (70) and surrounds only a part of the cardan shaft bearing (104) and the insulator (90), wherein the electromagnet (120) is selectively activated to move the cardan shaft bearing (104) within the bearing receiving zone (82).

Description

INTRODUCTION

[0001] The subject matter of the invention relates to the field of vehicles and in particular to a magnetically stabilized cardan shaft bearing system and a vehicle equipped therewith.

[0002] Certain vehicles may include a driveshaft or cardan shaft composed of several components. Typically, a multi-section cardan shaft has a support located between the first and second ends of the multi-section shaft. Generally, the support is positioned centrally along the multi-section shaft. The support may contain a bearing located within a compliant bushing. From US 6,960,024 B2, it is known that the support contains a magnetic coil surrounding the shaft, which can be used to modify the flow resistance of a rheological fluid with which an annular swarm is impregnated within the support. The bearing supports rotational forces on the cardan shaft, while the compliant bushing absorbs radial forces. At certain speeds, undesirable vibrations may develop due to the elasticity of the bushing.Accordingly, it is desirable to provide a carrier for a multi-part cardan shaft that can withstand vibrations.

[0003] From WO 01 / 55 633 A1 it is also known to support a rotating shaft on a housing by means of two magnets arranged perpendicular to each other, wherein the magnets are mounted on the housing by means of rubber pads.

[0004] Regarding the further state of the art, reference is made at this point to the publications KR 10 2004 0 036 267 A and US 5 126 641 A.

[0005] The invention is based on the objective of damping and eliminating unwanted vibrations of a cardan shaft. SUMMARY

[0006] This problem is solved with a cardan shaft bearing system having the features of claim 1 and with a vehicle having the features of claim 7.

[0007] In addition to one or more of the features described above or below, or as an alternative, further embodiments may include a bearing stability control module that is operatively connected to the electromagnet, wherein the bearing stability control module selectively activates the electromagnet based on a vehicle condition.

[0008] In addition to one or more of the features described above or below, or as an alternative, further embodiments could include a vehicle speed sensor that is operatively connected to the bearing stability control module, wherein the vehicle condition includes the vehicle speed.

[0009] In addition to one or more of the features described above or below, or as an alternative, further embodiments could include a vibration sensor that is operatively connected to the bearing stability control module, wherein the vehicle condition includes undesired vibrations.

[0010] In addition to one or more of the features described above or below, or as an alternative, further embodiments could include those in which the unwanted vibrations include unwanted cardan shaft vibrations.

[0011] In addition to one or more of the features described above or below, or as an alternative, further embodiments could include such features, wherein the sensor module is attached to the holder.

[0012] In addition to one or more of the features described above or below, or as an alternative, further embodiments may include a bearing stability control module that is operatively connected to the electromagnet, wherein the bearing stability control module selectively activates the electromagnet based on a vehicle condition.

[0013] In addition to one or more of the features described above or below, or as an alternative, further embodiments could include a vehicle speed sensor that is operatively connected to the bearing stability control module, wherein the vehicle condition includes the vehicle speed.

[0014] In addition to one or more of the features described above or below, or as an alternative, further embodiments could include a vibration sensor that is operatively connected to the bearing stability control module, wherein the vehicle condition includes undesired vibrations.

[0015] In addition to one or more of the features described above or below, or as an alternative, further embodiments could include those in which the unwanted vibrations include unwanted cardan shaft vibrations.

[0016] In addition to one or more of the features described above or below, or as an alternative, further embodiments could include such features, wherein the vibration sensor is attached to the bracket.

[0017] In addition to one or more of the features described above or below, or as an alternative, further embodiments could include the cardan shaft comprising a multi-part cardan shaft comprising a first cardan shaft element and a second cardan shaft element operatively connected at a joint.

[0018] In addition to one or more of the features described above or below, or as an alternative, further embodiments could include such features, wherein the magnetically stabilized cardan shaft bearing system is arranged adjacent to the joint.

[0019] According to yet another aspect of an exemplary embodiment, a method for stabilizing a cardan shaft bearing includes detecting a vehicle condition that affects the position of a cardan shaft bearing in a bracket, activating an electromagnet that surrounds part of the cardan shaft bearing based on the vehicle condition, and moving the cardan shaft bearing to a predetermined position in a bearing receiving zone of the carrier.

[0020] In addition to one or more of the features described above or below, or as an alternative, further embodiments could include such features, wherein moving the bearing into the predetermined position essentially involves centering the cardan shaft bearing in the bearing receiving area.

[0021] In addition to one or more of the features described above or below, or as an alternative, further embodiments could include such features, wherein the detection of the vehicle state includes the detection of a vehicle speed.

[0022] In addition to one or more of the features described above or below, or as an alternative, further embodiments could include such features as the activation of the electromagnet based on the vehicle state involving the activation of the electromagnet when the vehicle speed is within a predetermined speed range.

[0023] In addition to one or more of the features described above or below, or as an alternative, further embodiments could include such features, wherein the detection of the vehicle state includes the detection of a vehicle speed.

[0024] In addition to one or more of the features described above or below, or as an alternative, further embodiments could include such features as the activation of the electromagnet based on the vehicle condition, including the activation of the electromagnet upon detection of unwanted cardan shaft vibrations above a predetermined vibration threshold.

[0025] The aforementioned features and advantages, as well as further features and advantages of the invention, are readily apparent from the following detailed description of the invention in conjunction with the associated drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Other features, advantages and details appear only as examples in the following detailed description of the embodiments, the detailed description referring to the drawings, wherein the following applies: Fig. Figure 1 shows a vehicle with a magnetically stabilized cardan shaft bearing system according to one aspect of an exemplary embodiment; Fig. Figure 2 is a schematic representation of the magnetically stabilized cardan shaft bearing system according to one aspect of an exemplary embodiment; and Fig. Figure 3 is a block diagram illustrating the magnetically stabilized cardan shaft bearing system according to one aspect of an exemplary embodiment. DETAILED DESCRIPTION

[0027] It should be understood that in the drawings, corresponding reference numerals denote identical or corresponding parts and features. As used herein, the term "module" or "unit" refers to an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), an electronic circuit, an electronic computer processor (shared, dedicated, or grouped), and memory executing one or more software or firmware programs, a hardware microcontroller, a combinational logic circuit, and / or other suitable components providing the described functionality. When implemented in software, a module may be implemented in memory as a non-volatile, computer-readable storage medium that can be read by a processing circuit and stores instructions to be executed by the processing circuit to perform a procedure.

[0028] According to an exemplary embodiment, a vehicle is generally equipped with 10 in Fig. Figure 1 shows the vehicle 10, which includes a frame 12 supporting a body 18 and a drivetrain 28. The drivetrain 28 includes a drive unit 30, which can take the form of an engine 32. The engine 32 can be an internal combustion engine, an electric motor, a hybrid engine, or the like. The engine 32 is coupled to a transmission 34, which in turn is operatively connected to a differential 36. The differential 36 is operatively connected to a first wheel 38 via a first axle 39 and to a second wheel 42 via a second axle 43. The transmission 34 is connected to the differential 36 via a driveshaft 46. In the exemplary aspect shown, the driveshaft 46 takes the form of a multi-section driveshaft, comprising a first driveshaft element 48 connected to a second driveshaft element 49 at a joint 50.

[0029] According to one aspect of an exemplary embodiment, the cardan shaft 46 is mechanically supported on the frame 12 by a magnetically stabilized cardan shaft bearing system 60, which may be arranged adjacent to the joint 50. Referring to Fig. Figure 2 includes the magnetically stabilized cardan shaft bearing system 60 and a bracket 70 which can be attached to a cross member (not separately designated) of the frame 12. The bracket 70 includes a base section 72 provided with a flange 73 having a first channel 76 and a second channel 77. The first and second channels 76 and 77 can accommodate mechanical fasteners (not shown) that connect the bracket 70 to the frame 12.

[0030] In further accordance with an exemplary aspect, the bracket 70 includes a bearing support section 80, which defines a bearing receiving zone 82 with an inner annular surface 84. An insulator 90 is arranged in the bearing receiving zone 82. According to the invention, the insulator 90 is formed from a flexible material (e.g., an elastomeric material) and has an outer section 92, which is supported on the inner annular surface 84, and an inner section 94. The inner section 94 is connected to the outer section 92 via a number of web elements, one of which is designated 96. It is understood that the number, arrangement, and position of the web elements 96 can vary. The inner section 94 contains an opening 98 with an annular surface section 100. A bearing 104 is arranged in the opening 98.The bearing 104 comprises an outer race 106, which is supported by an annular surface section 100, an inner race 107, and a plurality of bearing elements 109 arranged between them. The inner race 107 includes a passage 112 that can accommodate and rotatably support the cardan shaft 46.

[0031] According to one aspect of an exemplary embodiment, the bracket 70 carries an electromagnet 120 comprising a body 123 that only partially surrounds the bearing 104. According to one exemplary aspect, the electromagnet 120 is located on one side of the bearing 104 opposite to the direction of gravity. However, it is understood that the specific position, shape, and size of the electromagnet 120 may vary. With reference to Fig.3. The electromagnet 120 is electrically connected to a bearing stability control module 130, which may include a processor 134 and a memory 136. The bearing stability control module 130 may also be electrically connected to a vehicle speed sensor 140 and a cardan shaft vibration sensor 142. The bearing stability control module 130 selectively activates the electromagnet 120 based on detected vehicle conditions to prevent unwanted vibrations of the cardan shaft 46. Upon activation, the electromagnet 120 pulls the bearing 104 to a predetermined position within the bearing support zone 82 to prevent and / or correct misalignments of the cardan shaft 46 that could lead to vibrations.

[0032] According to one aspect of an exemplary embodiment, the electromagnet 120 can displace the bearing 104 to be positioned substantially centrally within the bearing support zone 82. It is understood that the electromagnet 120 can displace the bearing 104 to an off-center, yet stabilized position within the bearing support zone 82. An off-center position may be desirable to apply a load to or relieve sections of the insulator 90 and / or to adjust the stiffness parameters and vibration characteristics of the bearing 104.

[0033] According to one aspect of an exemplary embodiment, the bearing stability control module 130 receives input from the vehicle speed sensor 140 regarding the vehicle speed. Upon detecting that the vehicle 10 has reached a predetermined speed, the bearing stability control module 130 activates the electromagnet 120. For example, a predetermined speed range can be stored in the memory 136. The predetermined speed range can represent a vehicle speed associated with the cardan shaft vibration. The bearing stability control module 130 can operate in a proactive mode and keep the electromagnet 120 in an activated state as long as the vehicle 10 travels at a speed within the predetermined speed range.Furthermore, the bearing stability control module 130 can activate the electromagnet 120 shortly before a vehicle enters the predetermined speed range and maintain an activation state for a short period of time after the vehicle 10 has left the predetermined speed range.

[0034] In addition to proactive operation, such as activating electromagnet 120 when the vehicle 10 enters a predetermined speed range, the bearing stability control module 130 can also be reactive and activate electromagnet 120 when the cardan shaft vibration sensor 142 detects unwanted vibrations. Unwanted vibrations may include unwanted cardan shaft vibrations that exceed a predetermined vibration threshold. In each mode, the bearing stability control module 130 maintains a substantially centered position of the bearing 104 during selected modes of vehicle operation to reduce vibrations and extend component service life.

Claims

[1] Magnetically stabilized cardan shaft bearing system (60), comprising: a holder (70) with a bearing receiving zone (82) with an inner annular surface (84); an insulator (90) made of a flexible material, arranged in the bearing receiving zone (82), wherein the insulator (90) has an outer section (92) supported on the inner annular surface (84) and an inner section (94) connected to the outer section (92) via several web elements (96), wherein the inner section (94) includes an opening (98) with an annular surface section (100); a cardan shaft bearing (104) arranged in the bearing receiving zone (82) and supported by the insulator (90), wherein the cardan shaft bearing (104) is arranged in the opening (98) of the inner section (94), the cardan shaft bearing (104) comprising an outer race (106) supported by the annular surface section (100), an inner race (107), and a plurality of bearing elements (109) between the outer race (106) and the inner race (107), wherein the inner race (107) of the cardan shaft bearing (104) includes a passage (112) capable of receiving a cardan shaft (46) for a vehicle rotatably supported; and an electromagnet (120) which is mounted in the holder (70) and surrounds only a part of the cardan shaft bearing (104) and the insulator (90), wherein the electromagnet (120) is selectively activated to move the cardan shaft bearing (104) within the bearing receiving zone (82). [2] A magnetically stabilized cardan shaft bearing system according to claim 1, further comprising: a bearing stability control module (130) operatively connected to the electromagnet (120), wherein the bearing stability control module (130) selectively activates the electromagnet (120) based on a vehicle state. [3] Magnetically stabilized cardan shaft bearing system according to claim 2, further comprising: a vehicle speed sensor (140) which is operatively connected to the bearing stability control module (130), wherein the vehicle state includes the vehicle speed. [4] Magnetically stabilized cardan shaft bearing system according to claim 2, further comprising: a vibration sensor (142) which is operatively connected to the bearing stability control module (130), wherein the vehicle condition includes undesired vibrations. [5] Magnetically stabilized cardan shaft bearing system according to claim 4, wherein the unwanted vibrations include unwanted cardan shaft vibrations. [6] Magnetically stabilized cardan shaft bearing system according to claim 5, wherein the vibration sensor is attached to the bracket (70). [7] Vehicle (10), comprising: a frame (12); a body (18) supported by the frame (12); a drive train (28) connected to the frame (12), wherein the drive train (28) comprises a drive motor (32), a transmission (34), a differential (36) and a cardan shaft (46) which effectively connects the transmission (34) and the differential (36); and a magnetically stabilized cardan shaft bearing system (60) which is operatively connected to the cardan shaft (46), wherein the magnetically stabilizing cardan shaft bearing system (60) comprises: a holder (70) with a bearing receiving zone (82) with an inner annular surface (84); an insulator (90) made of a flexible material, arranged in the bearing receiving zone (82), wherein the insulator (90) has an outer section 92 supported on the inner annular surface (84) and an inner section (94) connected to the outer section (92) via several web elements (96), wherein the inner section (94) includes an opening (98) with an annular surface section (100); a cardan shaft bearing (104) arranged in the bearing receiving zone (82) and supported by the insulator (90), wherein the cardan shaft bearing (104) is arranged in the opening (98) of the inner section (94), the cardan shaft bearing (104) comprising an outer race (106) supported by the annular surface section (100), an inner race (107), and a plurality of bearing elements (109) between the outer race (106) and the inner race (107), wherein the inner race (107) of the cardan shaft bearing (104) includes a passage (112) capable of receiving a cardan shaft (46) for a vehicle rotatably supported; and an electromagnet (120) which is mounted in the holder (70) and surrounds only a part of the cardan shaft bearing (104) and the insulator (90), wherein the electromagnet (120) is selectively activated to move the cardan shaft bearing (104) within the bearing receiving zone (82). [8] Vehicle according to claim 7, further comprising: a bearing stability control module (130) operatively connected to the electromagnet (120), wherein the bearing stability control module (130) selectively activates the electromagnet (120) based on a vehicle state. [9] Vehicle according to claim 8, further comprising: a vehicle speed sensor (140) which is operatively connected to the bearing stability control module (130), wherein the vehicle state includes the vehicle speed. [10] Vehicle according to claim 8, further comprising: a vibration sensor (142) which is operatively connected to the bearing stability control module (130), wherein the vehicle condition includes undesired vibrations.

Images