JP2019068560A - Wheel bearing device with generator - Google Patents

Abstract

To make it possible to be stored in a wheel without significant changes in components around the wheel, efficiently dissipate heat, prevent burnout of a coil, thermal demagnetization of a magnet, and deterioration of braking performance, and increase an output.SOLUTION: The wheel bearing device with a generator includes: a wheel bearing 2; and a generator 3 having a stator 18 attached to an outer ring 4 which is a fixed ring of the wheel bearing 2 and a motor rotor 19 attached to a hub flange 7 of an inner ring 5 which is a rotary ring. A brake rotor 12 is composed of a disc-like portion 12a mounted in a stacked manner on the hub flange 7, a cylindrical portion 12b, and an outer peripheral portion 12c. The stator 18 and a part or all of the motor rotor 19 are located in a space formed by the disk-like portion 12a and the cylindrical portion 12b of the brake rotor 12. A plurality of vent holes 23 is dispersed throughout a cylindrical portion 1b of the brake rotor 12.SELECTED DRAWING: Figure 1

Description

  The present invention is provided separately from an internal combustion engine serving as a main drive source, a motor, or a combination thereof in a vehicle such as a front wheel drive or a rear wheel drive to improve the fuel consumption of the vehicle or to further improve the traveling performance and braking. The present invention relates to a bearing device for a wheel with a generator that improves vehicle performance such as performance.

  The bearing for the wheel to which the wheel is attached is protruded and attached to one side of the frame part (knuckle part) of the undercarriage frame part of the suspension system, and the motor for driving by rotating the rotating wheel of the bearing for the wheel There has been proposed an electric vehicle which is mounted on one side of the housing so as to protrude (for example, Patent Document 1). The motor is also used as a generator by regenerative braking.

Patent No. 4348941 gazette

  In the configuration described in Patent Document 1, the motor projects in the axial direction of the axle, and it is necessary to change the underbody structure of the suspension system. Furthermore, if the radial dimension of the motor casing is increased in order to improve the generated electric power and the motor torque, the motor casing interferes with the surrounding suspension system, so it is common to incorporate a reduction gear.

  Therefore, the applicant has proposed a direct drive system in which the motor is incorporated in the brake rotor, the radial dimension of the motor is secured, the mounting portion is not largely remodeled, and the reduction gear is not used. Application 2016-184295). The motor is used as a generator during regenerative braking.

  However, when the motor is operated for traveling drive or regenerative braking, heat is generated due to iron loss and copper loss, and at the time of braking, a heat source is also present around the generator due to the frictional heat of the brake rotor and the brake pad. In the configuration in which the motor is incorporated inside the brake rotor, the area of the surface of the motor in contact with air is small, so the heat dissipation is poor, and the temperature rise of the motor causes deterioration in the insulation performance of the coil etc., causing burnout. If current is limited to prevent drive performance and generator performance degradation due to heat demagnetization of the magnet, and burning and demagnetization of the coil, the drive and power generation performance can not be sufficiently exhibited. In addition, the axle bearings are also exposed to high temperatures for a long time, which leads to deterioration of the lubricating oil and strength reduction of the metal material.

More specifically, when the motor is incorporated in the brake rotor as described above, the motor can be efficiently incorporated in the wheel, but in addition to the heat generation from the brake rotor and the heat generation from the motor The frictional heat generated by the rotation of the hub wheel causes the heat source to be concentrated inside the brake rotor that is the component part. Therefore, the heat generated inside the brake rotor can be a high temperature because only the heat radiation of the brake rotor itself and the heat conduction through the contact portion with the vehicle body have a heat radiation path to the outside. When the temperature of the brake becomes high, the heat is transferred to the brake fluid, and there is a possibility that the vapor lock due to the generation of air bubbles in the fluid, the fading phenomenon due to the overheating of the brake pad, the excessive wear of the brake pad and the like may occur. In addition, when the temperature of the power assisting motor becomes high, destruction of the insulating film of the motor coil or thermal demagnetization of the motor occurs in the case of a magnet type motor, which significantly reduces the performance of the motor. In the wheel bearing, thermal deterioration of the lubricant and a decrease in strength of the metal material occur to reduce the bearing life.
In the above example, the case where the motor is used as a generator has been described, but the same problem as described above arises in the case of using only for power generation.

  The present invention solves the above-mentioned problems, can be stored in the wheel without significant changes in the components around the underbody, and can efficiently release the heat, and the coil burnout and magnet It is an object of the present invention to provide a bearing device for a wheel with a generator which can prevent the thermal demagnetization and the deterioration of the braking performance and can increase the output.

A generator-equipped wheel bearing apparatus according to the present invention has a fixed wheel and a hub flange, and is rotatably supported by the fixed wheel via a rolling element, and a wheel and a brake rotor of a vehicle are attached to the hub flange. A wheel bearing having a wheel;
A generator-equipped wheel bearing apparatus comprising: a stator attached to the fixed wheel; and a generator having a motor rotor attached to the rotating wheel,
The brake rotor is a disc-like portion attached to the hub flange so as to be overlapped, a cylindrical portion extending from the outer periphery of the disc-like portion to the outer periphery of the generator, and radially outward from the tip of the cylindrical portion It is an outer peripheral part that extends to the peripheral side and becomes the part where the brake caliper is pressed.
A part or all of the stator and the motor rotor are located in a space formed by the disc-like portion of the brake rotor and the cylindrical portion;
A plurality of vent holes are dispersed throughout the cylindrical portion of the brake rotor.

According to this configuration, the entire generator is smaller in diameter than the cylindrical portion of the brake rotor, and is located in the axial range from the hub flange of the wheel bearing to the undercarriage part, so that the conventional undercarriage is It can be stored in the wheel without major modifications to the structure.
Since the brake rotor has a plurality of vent holes dispersed throughout the cylindrical portion, the heat generated from the generator can be externally output by increasing the area where the generator located on the inner diameter side of the brake rotor contacts the external air. Can be released efficiently. As described above, since the heat can be released efficiently, it is possible to prevent the burning of the coil, the thermal demagnetization of the magnet, and the deterioration of the braking performance, and to increase the power generation output. Furthermore, the deterioration of the lubricating oil in the bearing and the reduction in the strength of the bearing material can be prevented.
Further, since air cooling is employed, it is not necessary to arrange piping for cooling, which also makes it possible to apply the bearing apparatus for a wheel with a generator without significant modification to the conventional undercarriage structure.

In the present invention, the generator may be a drive assisting motor that rotationally drives the wheels of the vehicle by being supplied with power.
As described above, by configuring the generator with the driving assistance motor, it is possible to perform driving assistance by rotating electric power generation by regenerative braking and by power feeding.
Thus, when it comprises with a motor, since temperature fall can be aimed at by thermal radiation, feed current can be enlarged and a fall of driving force can be prevented.

In the present invention, it is preferable that the plurality of vent holes be arranged regularly in the entire cylindrical portion of the brake rotor.
If the vents are regularly arranged, heat can be more efficiently dissipated and local strength reduction is prevented.

When the vent holes are aligned in this manner, the plurality of vent holes are arranged circumferentially at a plurality of axial locations in the cylindrical portion of the brake rotor, and axially adjacent to each other. The vents in the array may be circumferentially offset from one another.
The brake rotor generates a torsional stress in the cylindrical portion when it is held between the brake calipers and braked. In this case, if the vent holes aligned in the circumferential direction at a plurality of locations in the axial direction of the cylindrical portion are at the same circumferential position, the length between the vent holes is short. There is a concern that the second moment of area decreases and the torsional rigidity is insufficient and the durability can not be satisfied.
On the other hand, when the positions of the respective air holes in the axially adjacent arrangement are mutually offset in the circumferential direction, the moment of inertia of the cross section in the axial direction of the brake rotor becomes large, and the torsional rigidity of the brake rotor is high. Become. Therefore, the durability of the brake rotor is improved.

  The shape of the vent is preferably circular. The shape of the vent can be any shape such as a polygon other than a circle, but if it is a polygon, stress concentration will occur at the corners and weight reduction by thinning the brake rotor etc. There is a risk of lack of strength. On the other hand, when it is circular, stress concentration is unlikely to occur and the durability is excellent.

In the present invention, the generator may be an outer rotor type in which a rotor is positioned on the outer periphery of a stator.
In the outer rotor type, since the moment generation position is on the outer diameter side, the efficiency of power generation is superior to that of the inner rotor type. In the case of the outer rotor type, the rotor of the generator can be configured to be in contact with or close to the cylindrical portion of the brake rotor, in which case the effect of cooling by providing the vents is more effective. To be

  A generator-equipped wheel bearing apparatus according to the present invention has a fixed wheel and a hub flange, and is rotatably supported by the fixed wheel via a rolling element, and a wheel and a brake rotor of a vehicle are attached to the hub flange. A generator-equipped wheel bearing apparatus comprising: a wheel bearing having a wheel; a stator attached to the fixed wheel; and a generator having a motor rotor attached to the rotating wheel, the brake rotor being a brake rotor A disc-like portion attached to the hub flange in an overlapping manner, a cylindrical portion extending from an outer periphery of the disc-like portion to an outer peripheral side of the generator, and a brake extending radially outward from a tip of the cylindrical portion The stator and the motor rotor are partially or entirely formed of the disc-like portion of the brake rotor and the cylindrical portion. And, since it has a plurality of vent holes dispersed throughout the cylindrical portion of the brake rotor, it can be stored in the wheel without major changes in components around the wheel. And, heat can be released efficiently, burnout of the coil, thermal demagnetization of the magnet, deterioration of the brake performance can be prevented, and the output can be increased.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing of the bearing apparatus for wheels with a generator which concerns on 1st Embodiment of this invention. It is a perspective view which shows an example of the brake rotor of the bearing apparatus for wheels with a generator. It is a perspective view which shows the modification of the brake rotor. It is a perspective view which shows the other modification of the brake rotor. It is a perspective view which shows the other modification of the brake rotor. It is a perspective view which shows the other modification of the brake rotor. It is a perspective view of an analysis model of the brake rotor. (A) (b) is a figure which shows the analysis result seen from the outer side and inner side of the brake rotor which did not have a vent, respectively. (A) and (b) are figures which show the analysis result seen from the outer side and inner side of the brake rotor of FIG. 2, respectively. (A) and (b) are figures which show the analysis result seen from the outer side and inner side of the brake rotor of FIG. 5, respectively. (A) and (b) are figures which show the analysis result seen from the outer side and inner side of the brake rotor of FIG. 3, respectively. (A) and (b) are figures which show the analysis result seen from the outer side and inner side of the brake rotor of FIG. 4, respectively. (A) and (b) are figures which show the analysis result seen from the outer side and inner side of the brake rotor of FIG. 6, respectively. (A) is a graph of the stress value ratio which shows the result of stress analysis of the brake rotor according to vent shape, (b) is a graph of the stress value ratio which shows the result of stress analysis of the brake rotor according to vent arrangement. BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram which shows the conceptual structure of the system for vehicles using the bearing apparatus for wheels with a generator which concerns on 1st Embodiment. It is a power supply system figure used as an example of the vehicles carrying the system for vehicles. It is explanatory drawing of the concept of the system for other vehicles using the bearing apparatus for wheels with a generator.

  A generator-equipped wheel bearing apparatus according to a first embodiment of the present invention will be described with reference to FIGS. 1 and 2. The generator-equipped wheel bearing device 1 includes a wheel bearing 2 and a generator 3.

<About wheel bearing 2>
The wheel bearing 2 has an outer ring 4 which is a fixed ring, rolling elements 6 in double rows, and an inner ring 5 which is a rotating ring. The inner ring 5 is rotatably supported by the outer ring 4 via the rolling elements 6 in double rows. The outer ring 4 is composed of an outer ring main body 4a having a raceway surface and an outer peripheral member 4b on the outer periphery thereof. The inner ring 5 has a hub flange 7 at a location protruding toward the outboard side in the axial direction with respect to the outer ring 4. The outer ring 4 is attached to an underframe frame part 8 such as a knuckle or the like with a bolt (not shown) at a vehicle mounting surface 4a which is an end on the opposite side (inboard side) to the hub flange 7 to support the weight of the vehicle. . In this specification, in the state where the generator-equipped wheel bearing device 1 is mounted on a vehicle, the side that is closer to the outer side in the vehicle width direction of the vehicle is called the outboard side, and is closer to the center in the vehicle width direction of the vehicle. The side is called the inboard side.

  The rim 11 of the wheel 10 and the brake rotor 12 are attached to the side surface on the outboard side of the hub flange 7 by the hub bolt 13 in a state where the rim 11 and the brake rotor 12 overlap in the axial direction. A tire (not shown) is attached to the outer periphery of the rim 11.

<About the brake 17>
The brake 17 is a friction brake provided with a disc type brake rotor 12 and a brake caliper 22. The brake rotor 12 has an annular flat plate-like disk-like portion 12a overlapping the hub flange 7, a cylindrical portion 12b extending from the outer periphery of the disk-like portion 12a to the outer periphery of the generator 3, and the cylindrical portion It has an outer peripheral portion 12c extending radially outward from the tip end of 12b. The brake rotor 12 is made of, for example, a pressed product of a steel plate.

  The brake caliper 22 has a pair of friction pads 22 a sandwiching the outer peripheral portion 12 c of the brake rotor 12. The brake caliper 22 is attached to the underbody frame part 8. The brake caliper 22 may be either hydraulic or mechanical, or may be electric motor.

<About generator 3>
The generator 3 is a drive assisting electric motor capable of rotationally driving the wheel 10 by generating power by rotation of the wheel 10 and supplying power. The generator 3 has a stator 18 attached to the outer peripheral surface of the outer ring 4 and a motor rotor 19 attached to the hub flange 7 of the inner ring 5. The generator 3 in the illustrated example may be a synchronous motor such as an outer rotor type IPM (Interior Permanent Magnet Motor) synchronous motor.

  In addition, the generator 3 can adopt various types such as a switched reluctance motor (abbreviation: SR motor), an induction motor (induction motor; abbreviation: IM) and the like. In the synchronous motor, each type of distributed winding and concentrated winding can be adopted as a winding type of the stator 18.

  The stator 18 has a core 18a and coils 18b wound around the teeth of the core 18a. The coil 18 b is connected to the wiring 25. The motor rotor 19 includes a rotating case 19a serving as a motor case, a magnetic body 19b provided on the inner periphery of the rotating case 19a, and a permanent magnet (not shown) incorporated in the magnetic body 19b. It is attached to the flange 7. The outer peripheral surface of the rotating case 19a on the outboard side is fixed to the outer peripheral surface of the hub flange 7 by, for example, fitting, welding, adhesion or the like. The outer peripheral surface of the rotation case 19 a is in contact with or in proximity to the inner peripheral surface of the cylindrical portion 12 b of the brake rotor 12. A motor shield 21 is attached to one end on the inboard side of the rotation case 19a. The motor shield 21 closes one end on the inboard side of the rotation case 19a, and prevents foreign matter from entering the interior of the generator 3 from the underside frame part 8 side.

  The whole of the generator 3 is smaller in diameter than the outer peripheral portion 12 b of the brake rotor 12. Furthermore, the whole of the generator 3 except for the mounting portion to the hub flange 7 is located in the axial range between the inboard vehicle body mounting surface 4 a of the wheel bearing 2 and the hub flange 7. That is, the generator 3 is accommodated in the radial range between the outer peripheral portion 12 b of the brake rotor 12 and the outer periphery of the outer ring 4, and for the axial direction range, power generation is performed in the cylindrical portion 12 ba in the outer peripheral portion 12 b of the brake rotor 12. A part of the machine 3 (half on the outboard side) is included. The axial range of the generator 3 may extend to a position in contact with the undercarriage frame component 8.

<Ventilation hole 23 of brake rotor 12>
In the generator-equipped wheel bearing apparatus of the above-described configuration, as shown in FIG. 2, a plurality of vent holes 23 are provided dispersed throughout the cylindrical portion 12 b of the brake rotor 12. In the example of the figure, the vents 23 are circular and are arranged regularly in a grid. That is, the vent holes 23 form an array L aligned in the circumferential direction at a plurality of locations in the axial direction of the cylindrical portion 12 b of the brake rotor 12, and the vent holes 23 in the array adjacent in the axial direction The same position in the direction.

  According to the generator-equipped wheel bearing apparatus 1 having this configuration, the whole of the generator 3 has a diameter smaller than that of the cylindrical portion 12b of the brake rotor 12, and from the hub flange of the wheel bearing 2 to the vehicle mounting side end 4a. Being located in the axial range up to, it can be stored in the wheel without major modifications to the conventional undercarriage structure.

Since the brake rotor 12 has a plurality of vent holes 23 in the cylindrical portion 12b, the area of the generator 3 serving as a motor located on the inner diameter side of the brake rotor 12 is increased by contacting the external air, thereby driving or generating electricity. The heat generated from the generator 3 can be efficiently released to the outside. The vent holes 23 are dispersedly provided in the entire cylindrical portion 12b, so the heat radiation can be performed more efficiently. Since the vent holes 23 are arranged regularly, the local strength reduction due to the formation of the vent holes 23 of the brake rotor 12 is prevented.
As described above, since the heat can be efficiently released, it is possible to prevent the burnout of the coil 18b, the thermal demagnetization of the permanent magnet, and the deterioration of the braking performance, and to increase the motor drive output and the power generation output. Furthermore, the deterioration of the lubricating oil in the wheel bearing 2 and the strength reduction of the bearing material can be prevented.
Further, since air cooling is used, it is not necessary to arrange piping for cooling, which also makes it possible to apply the generator-equipped wheel bearing device 1 to a vehicle without significant modification to the conventional undercarriage structure.

Although the vent holes 23 are circular holes in the example of FIG. 2, any shape can be adopted. Also, various arrangements can be adopted for the arrangement of the vent holes 23.
3 to 6 each show an example in which the shape and / or arrangement of the vent holes 23 or both of them are changed for the brake rotor 12 in the generator equipped wheel bearing apparatus 1 of the above embodiment.

In the example of FIG. 3, the shape of the vent holes 23 is rectangular, and the arrangement of the arrangement holes 23 is square as in the example of FIG. 2.
In the example of FIG. 4, the shape of the air vents 23 is a rhombus, and the arrangement of the arrangement holes 23 is square as in the example of FIG. 2.
In the example of FIG. 5, the shape of the vents 23 is circular, and the arrangement is staggered. That is, in this example, in the arrangement, the vent holes 23 form an array L (five rows in the illustrated example) aligned circumferentially at a plurality of axial positions of the cylindrical portion 12b of the brake rotor 12, and the axial direction The vents 3 of the array L adjacent to each other are offset in position in the circumferential direction from each other. In the example of the same figure, the ventilation holes 3 of the adjacent arrangement L are mutually shifted by 1/2 of the arrangement pitch in the circumferential direction.
In the example of FIG. 6, the shape of the vents 23 is rectangular as in the example of FIG. 3, and the arrangement is staggered as in the example of FIG.

The arrangement of the vents 23 is preferably a staggered arrangement for the following reason. When the brake rotor 12 is held between the brake calipers 22 and braked, a torsional stress is generated in the cylindrical portion 12 b. In this case, as in the examples of FIGS. 2 to 4, if the vent holes in the circumferential rows L of the cylindrical portions 12 b are at the same position in the circumferential direction, the length W between the vent holes 23 is As a result, the moment of inertia of the axial cross section of the portion A where the vents 23 are aligned in the axial direction of the brake rotor 12 is reduced, and there is a concern that the torsional rigidity is insufficient and the durability is lowered.
On the other hand, if the positions of the air holes 23 of the array L adjacent in the axial direction are mutually offset in the circumferential direction as in the example of FIGS. 5 and 6, the air holes 23 of the brake rotor 12 exist. The second moment of area of the axial section at axial points A and A 'is increased, and the torsional rigidity of the brake rotor 12 is increased. Therefore, the durability of the brake rotor is improved.

  The shape of the vent hole 23 may be any shape as described above, but if it is a polygon, stress concentration occurs at the corner portions, and strength is achieved when weight reduction is achieved by thinning the brake rotor 12, etc. There is a risk of shortage. On the other hand, if it is circular like the example of FIG. 2, FIG. 5, it will become difficult to produce a stress concentration and will be excellent in durability.

  The analysis result of the brake rotor 12 is shown with FIGS. 7-14. FIG. 7 is an analysis model of the brake rotor 12. The analysis was performed in a state in which the brake pad contact surface of the brake rotor 12 is completely restrained, the hub bolt hole 13A is fastened in an imaginary rigid body, and a rotational moment is applied to the center of the brake rotor 12.

(A) and (b) of FIG. 8 to FIG. 13 are diagrams showing the stress state generated in the brake rotor 12 at the time of rotational moment load from the outside and the inside of the brake rotor 12, respectively. The stress state is indicated by Mises stress. The deeper it is, the larger the stress value.
FIG. 8 is an analysis result of an example in which the brake rotor 12 is a non-vented hole.
FIG. 9 is an analysis result of an example (FIG. 2) in which circular non-air-permeable holes 23 (round holes) are provided in a squared arrangement in the brake rotor 12.
FIG. 10 is an analysis result of an example (FIG. 5) in which circular non-air holes 23 (round holes) are provided in a staggered arrangement in the brake rotor 12.
FIG. 11 is an analysis result of an example (FIG. 3) in which rectangular vent holes 23 are provided in the brake rotor 12 in a grid arrangement.
FIG. 12 is an analysis result of an example (FIG. 5) in which the non-air-permeable holes 23 of a rhombic shape are provided on the brake rotor 12 in a grid arrangement.
FIG. 13 shows an analysis result with an example (FIG. 6) in which rectangular non-air holes 23 are provided in a staggered arrangement in the brake rotor 12.

  As can be seen from the above analysis results, the maximum von Mises stress generated in the vicinity of the vent hole 23 differs depending on the difference in the shape and the arrangement of the vent hole 23.

Based on the maximum von Mises stress generated in the cylindrical portion 12b of the brake rotor 12 in which the vent holes 23 are not provided, the ratio of the maximum von Mises stress generated in the vicinity of these vent holes under the shape condition of each vent hole 23 is shown in FIG. Show.
From FIG. 14, in the case of the circular hole shape staggering arrangement, the maximum von Mises stress generated between the air vents can be minimized with respect to the increase without the air vents.
Therefore, it can be seen that the shape and arrangement of the vents that provide ventilation performance without losing the torsional rigidity as much as possible are circular holes and are staggered.

<About the system for vehicles>
FIG. 15 is a block diagram showing a conceptual configuration of a vehicle system provided with the generator equipped wheel bearing apparatus 1 according to the embodiment using the first or other modification of each of the brake rotors.
In this vehicle system, the generator equipped wheel bearing device 1 is mounted on the driven wheel 10B in a vehicle having the driven wheel 10B mechanically disconnected from the main drive source. The wheel bearing 2 (FIG. 1) in the generator-equipped wheel bearing device 1 is a bearing that supports the driven wheel 10B.

  The main drive source 35 is an internal combustion engine such as a gasoline engine or a diesel engine, or a motor generator (electric motor), or a hybrid drive source combining both. The "motor generator" refers to an electric motor capable of generating power by rotation. In the illustrated example, the vehicle 30 is a front wheel drive vehicle whose front wheels are drive wheels 10A and rear wheels are driven wheels 10B, and the main drive source 35 has an internal combustion engine 35a and a motor generator 35b on the drive wheels side. It is a hybrid car (hereinafter sometimes referred to as "HEV").

  Specifically, it is a mild hybrid type in which the motor generator 35b on the drive wheel side is driven by a medium voltage such as 48V. Hybrids can be broadly divided into Strong Hybrids and Mild Hybrids, but Mild Hybrids, whose main drive source is an internal combustion engine, is a type that mainly assists driving with a motor when starting or accelerating. In the (electric car) mode, it can be distinguished from the strong hybrid because normal travel can be performed for a while but can not be performed for a long time. The internal combustion engine 35a of the example of the figure is connected to the drive shaft of the drive wheel 10A through the clutch 36 and the reduction gear 37, and the motor generator 35b on the drive wheel side is connected to the reduction gear 37.

  This vehicle system is provided in the generator 3 which is a motor generator for traveling assistance which rotationally drives the driven wheel 10B, the individual control means 39 which controls the generator 3, and the host ECU 40, the individual It includes an individual motor generator command means 45 for outputting a command for causing the control means 39 to perform drive and regeneration control. The generator 3 is connected to the storage means. The storage means may be a battery (storage battery) or a capacitor, a capacitor, etc. The type and mounting position on the vehicle 30 are not limited. In this embodiment, the low voltage battery 50 mounted on the vehicle 30 and Among the medium voltage batteries 49, the medium voltage battery 49 is used.

The driven wheel generator 3 is a direct drive motor that does not use a transmission. The generator 3 acts as a motor by supplying electric power, and also acts as a generator that converts kinetic energy of the vehicle 30 into electric power.
As the generator 3 has the motor rotor 19 (FIG. 1) attached to the inner ring 5 (FIG. 1) which is a hub wheel, when a current is applied to the generator 3, the inner ring 5 (FIG. 1) is rotationally driven. During power regeneration, regenerative power can be obtained by loading the induced voltage.

<About Control System of Vehicle 30>
The host ECU 40 is a unit that performs integrated control of the vehicle 30, and includes a torque command generation unit 43. The torque command generation unit 43 generates a torque command in accordance with signals of operation amounts respectively input from an accelerator operation unit 56 such as an accelerator pedal and a brake operation unit 57 such as a brake pedal. The vehicle 30 is provided with an internal combustion engine 35a and a motor generator 35b on the drive wheel side as the main drive source 35, and two generators 3 and 3 for driving the two driven wheels 10B and 10B, respectively. The host ECU 40 is provided with torque command distribution means 44 which distributes the commands according to the rules defined in the respective drive sources 35 a, 35 b, 3, 3.

  The torque command for the internal combustion engine 35a is transmitted to the internal combustion engine control means 47, and is used for valve opening control etc. by the internal combustion engine control means 47. A torque command to the drive wheel side generator motor 35b is transmitted to the drive wheel side motor generator control means 48 and executed. The torque command to the generators 3, 3 on the driven wheel side is transmitted to the individual control means 39, 39. The part of the torque command distribution means 44 to be output to the individual control means 39, 39 is referred to as an individual motor generator command means 45. The individual motor generator command means 45 gives the individual control means 39 a torque command as a command of a braking force with which the generator 3 shares braking by regenerative braking in response to the signal of the operation amount of the brake operation means 57. Also have.

  The individual control means 39 is an inverter device, and an inverter 41 for converting DC power of the medium voltage battery 49 into three-phase AC voltage, and a control unit 42 for controlling the output of the inverter 41 by PWM control etc. Have. The inverter 41 includes a bridge circuit (not shown) such as a semiconductor switching element or the like, and a charging circuit (not shown) for charging the regenerative power of the generator 3 to the medium voltage battery 49. Although the individual control means 39 is separately provided for the two generators 3 and 3, it is housed in one case, and the control unit 42 is shared by both the individual control means 39 and 39. Good.

  FIG. 16 is a power supply system diagram as an example of a vehicle equipped with the system for a vehicle shown in FIG. In the example of the figure, a low voltage battery 50 and a medium power battery 49 are provided as batteries, and the low voltage battery 50 is connected via a DC / DC converter 51. Although there are two generators 3, one is shown as a representative. The motor generator 35b on the drive wheel side of FIG. 15 is connected to the intermediate power system in parallel with the generator 3 on the driven wheel side, although illustration is omitted in FIG. A low voltage load 52 is connected to the low voltage system, and a medium voltage load 53 is connected to the medium voltage system. There are a plurality of low voltage loads 52 and a plurality of medium voltage loads 53, but one is representatively shown.

  The low voltage battery 50 is a battery generally used in various automobiles as a power supply of a control system or the like, and is, for example, 12 V or 24 V. The low voltage load 52 includes basic components such as a starter motor of the internal combustion engine 35a, lights, a host ECU 40, and other ECUs (not shown). The low voltage battery 50 may be referred to as an auxiliary battery for electrical equipment accessories, and the medium voltage battery 49 may be referred to as an auxiliary battery for an electric system or the like.

  The medium voltage battery 49 has a voltage higher than that of the low voltage battery 50 and lower than a high voltage battery (100 V or more, for example, about 200 to 400 V) used in a strong hybrid vehicle etc. It is a voltage that does not cause a problem, and a 48V battery used in recent years for mild hybrids is preferable. A medium voltage battery 49 such as a 48V battery can be mounted relatively easily on a vehicle equipped with a conventional internal combustion engine, and can reduce fuel consumption by power assist and regeneration with electric power as a mild hybrid.

  The medium voltage load 53 of the 48V system is the accessory part, and is a power assist motor which is the generator 3 on the drive wheel side, an electric pump, an electric power steering, a supercharger, an air compressor, or the like. By configuring the load of accessories with a 48V system, although the power assist output is lower than that of high voltage (100V or higher strong hybrid vehicles etc.), the risk of electric shock to occupants and maintenance workers can be reduced. it can. Since the insulation coating of the wire can be thinned, the weight and volume of the wire can be reduced. Further, since a large amount of power can be input / output with a current amount smaller than 12 V, the volume of the motor or generator can be reduced. From these things, it contributes to the fuel consumption reduction effect of vehicles.

  The vehicle system is suitable for accessory parts of such mild hybrid vehicles, and is applied as a power assist and a power regeneration part. Although CMGs, GMGs, and belt-driven starter motors (none of which are shown) may be employed conventionally in mild hybrid vehicles, all of them are power assists for internal combustion engines or power devices. Or because it regenerates, it is affected by the efficiency of the transmission device and speed reducer.

  On the other hand, since the vehicle system of this example is mounted on the driven wheel 10B, it is separated from the main drive source such as the internal combustion engine 35a and the electric motor (not shown), and the power is regenerated. Can use kinetic energy of the vehicle body 1 directly. In addition, when CMG, GMG, a belt drive type starter motor, etc. are mounted, it is necessary to consider considering from the design stage of the vehicle 30, and it is difficult to retrofit, but the system for this vehicle that fits in the driven wheel 10B The generator 3 can be mounted with the same number of steps as part replacement even if it is a complete vehicle, and a 48 V system can be configured even for a complete vehicle with only the internal combustion engine 35a. Another auxiliary drive motor generator 35b may be mounted on the vehicle equipped with the vehicle system of this embodiment as shown in FIG. At that time, the power assist amount and the regenerative electric energy for the vehicle 30 can be increased, which further contributes to the fuel consumption reduction.

  FIG. 17 shows an example in which the generator equipped wheel support bearing assembly 1 according to any of the embodiments is applied to the drive wheel 10A as a front wheel and the driven wheel 10B as a rear wheel. The drive wheel 10A is driven by the main drive source 35 consisting of an internal combustion engine via the clutch 36 and the reduction gear 7. In this front wheel drive vehicle, a generator equipped wheel support bearing assembly 1 is installed to support and assist the drive wheels 10A and the driven wheels 10B. As described above, the generator equipped wheel bearing apparatus 1 can be applied not only to the driven wheel 10B but also to the driving wheel 10A.

Although the system for vehicles shown in FIG. 15 has a function to generate electric power, it may be a system which does not rotate by feeding. In this case, the braking power can be generated by storing the regenerative power generated by the generator 3 in the medium voltage battery 49. The braking performance can also be improved by using it together with or using the mechanical brake operating means 57. When limited to the function of generating electric power as described above, the individual control means 39 can be configured as an AC / DC converter (not shown) rather than an inverter. The AC / DC converter device has a function of charging the regenerative power of the generator 3 to the middle voltage battery 49 by converting a three-phase AC voltage into a DC voltage, and the control method is easy compared to an inverter, Miniaturization is possible.

  In the embodiment, the whole of the generator 3 has a diameter smaller than that of the outer peripheral portion 12b of the brake rotor 12, and the whole of the generator 3 excluding the mounting portion to the hub flange 7 is the wheel bearing 2 Is arranged in the axial range between the inboard side of the vehicle mounting surface 4 a and the hub flange 7, but a part or all of the stator 12 and the motor rotor 19 correspond to the brake rotor 12. It may be located in the space formed by the disk-like portion 12a and the cylindrical portion 12b. The space formed by the disk-like portion 12 a and the cylindrical portion 12 b of the brake rotor 12 has an outer diameter smaller than that of the cylindrical portion 12 b of the brake rotor 12 and has an axial range of the cylindrical portion 12 b. This is a cylindrical space in which the inner diameter is equal to or larger than the minimum diameter of the disk-like portion 12a. When only a part of the stator 12 and the motor rotor 19 is located in this space, the remaining part of the stator 12 and the motor rotor 19 is, for example, an axial direction on the hub flange 7 side of the wheel bearing mounting surface of the undercarriage frame part 8 Placed in the range.

  As mentioned above, although the form for implementing this invention was demonstrated based on embodiment, embodiment disclosed this time is an illustration and restrictive at no points. The scope of the present invention is indicated not by the above description but by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

1 ... Wheel bearing device with generator 2 ... Wheel bearing 3 ... Generator 4 ... Outer ring (fixed wheel)
4a ... body mounting surface 5 ... inner ring (turning wheel)
6 Rolling element 7 Hub flange 12 Brake rotor 12b Cylindrical portion 18 Stator 19 Motor rotor 23 Ventilation holes

Claims (6)

A wheel bearing having a fixed wheel, and a wheel flange having a hub flange and rotatably supported by the fixed wheel via rolling elements and having the wheel and brake rotor of the vehicle attached to the hub flange;
A generator-equipped wheel bearing apparatus comprising: a stator attached to the fixed wheel; and a generator having a motor rotor attached to the rotating wheel,
The brake rotor is a disc-like portion attached to the hub flange so as to be overlapped, a cylindrical portion extending from the outer periphery of the disc-like portion to the outer periphery of the generator, and radially outward from the tip of the cylindrical portion It becomes an outer peripheral part which becomes the part which extends to the side where the brake caliper is pressed,
The stator and a part or all of the motor rotor are located in a space formed by the disc-like portion and the cylindrical portion of the brake rotor,
It has a plurality of vent holes dispersed throughout the cylindrical portion of the brake rotor,
Generator bearing wheel assembly.   The generator-equipped wheel bearing apparatus according to claim 1, wherein the generator is a travel assisting motor that rotationally drives the wheels of the vehicle by being supplied with electric power.   The bearing apparatus for a wheel with a generator according to claim 1 or 2, wherein the plurality of vent holes are regularly arranged in the entire cylindrical portion of the brake rotor. Wheel bearing device.   4. The generator-equipped wheel bearing apparatus according to claim 3, wherein the plurality of vent holes are arranged circumferentially at a plurality of axial locations in the cylindrical portion of the brake rotor in the axial direction. A device as claimed in any one of the preceding claims, wherein said vents in said adjacent array are circumferentially offset from one another.   The bearing device for a wheel with a generator according to any one of claims 1 to 4, wherein each of the vent holes is circular.   The bearing apparatus for a wheel with a generator according to any one of claims 1 to 5, wherein the generator is an outer rotor type in which a rotor is positioned on an outer periphery of a stator.

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