CN1736014A

CN1736014A - Electric power steering device

Info

Publication number: CN1736014A
Application number: CN 200380107971
Authority: CN
Inventors: 濑川彻; 百百雄志; 惠田广; 金泽显祯; 和田胜
Original assignee: NSK Ltd; NSK Steering Systems Co Ltd
Current assignee: NSK Ltd; NSK Steering Systems Co Ltd
Priority date: 2002-10-31
Filing date: 2003-10-31
Publication date: 2006-02-15
Also published as: JP2005312086A

Abstract

In an electric power steering apparatus that generates an auxiliary steering torque by a brushless motor in response to a steering torque applied on a steering wheel and transmits it to an output shaft of a steering mechanism while reducing it by means of a reduction gear, the apparatus comprises a rotor ( 10 ) to which a cylindrical permanent magnet for rotational driving ( 12 ) and a member to be detected ( 13 ) for detection of a rotational angle of the rotor are attached and a cylindrical stator ( 30 ) opposed to the rotor in which a laminated core ( 16 ) on which a coil is wound, detection means ( 17 ) for detecting the rotational angle of the rotor by the member to be detected and a terminal ( 19 ) for providing connection to the coil are integrally formed by resin molding. At least one bearing ( 8, 9 ) for rotatably supporting the rotor is disposed radially inside the stator and between the permanent magnet for rotational driving and the member to be detected.

Description

Electrically powered steering apparatus using same

Technical field

The present invention relates to a kind of electrically powered steering apparatus using same and a kind of brushless electric machine that is applicable to this device that is used for vehicle.

Background technology

In known vehicle electric transfer, provide the rotation output of the motor of assisted diversion moment to be delivered to the output shaft of transfer, so that in steering wheel steering operation process, increase the steering force that acts on the steering wheel by the geared system deceleration.In this electrically powered steering apparatus using same, transmission of power is to output shaft, and the power drive mechanism that is arranged on simultaneously in the housing reduces rotating speed of motor.

The main flow motor that is used for this electrically powered steering apparatus using same is brush motor normally.But in the last few years, this main flow motor had turned to brushless electric machine to improve reliability and further to raise the efficiency.

Figure 16 shows the electrically powered steering apparatus using same that adopts brushless electric machine.Output shaft 1 links to each other with the power shaft (not shown) by elements such as torque arm (not shown), and power shaft links to each other with the steering wheel (not shown), and the worm gear 2 of a worm gear reducer mechanism is fixedly connected on the output shaft 1.

The worm screw 5 that is rotatably supported in the gear box 3 by bearing 4 elements such as grade engages with worm gear 2.

The motor housing 7 of brushless electric machine links to each other with gear box 3 by the flange as dividing plate.The rotor 10 of brushless electric machine is rotatably supported on flange 6 and the motor housing 7 by bearing 8 and 9 respectively.Rotor 10 is connected by spline fitted part 11 with worm screw 5, thereby makes them can be in axial motion but can not relatively rotate with respect to each other.

At the radially outer of rotor 10 circumferentially to be provided with the permanent magnet that is used for rotating drive 12 of a column with lamination core 15 opposed modes.In addition, also be provided with the annular permanent magnet 13 that is used for sensing.

The radially inner side of motor housing 7 is provided with the stator 14 of a column.Stator 14 forms by resin molded, and it comprises the lamination core 16 that is wound with coil 15, detect the Hall integrated circuit 17 of the magnetic of the permanent magnet 13 that is used for sensing, be used to the terminals (bus) 19 the circuit board 18 of Hall integrated circuit 17 being installed and being used for connecting coil 15.

The cable 20 that is used for the terminals that link to each other with coil 15 and the terminals of the signal that is used to export Hall integrated circuit 17 links to each other with terminals (bus) 19 by welding or alternate manner.

In recent years, along with the increase of the vehicle class that adopts electrically powered steering apparatus using same, the required power output of electrically powered steering apparatus using same increases.Therefore, need to improve the power output of motor, but also the size that need reduce motor is to save the space.

If Hall integrated circuit 17 is arranged on the position of too close coil 15, Hall integrated circuit will be subjected to the influence of coil 15 magnetic and break down.Therefore, Hall integrated circuit must be arranged on the position of coil 15 certain distances (certain space).And this makes become unusual difficulty of the length that must reduce motor.

In addition, therefore the bearing pedestal and the flange that must be provided for block bearing 8,9 in the exterior circumferential or the end face of stator 14, are difficult to reduce have the length of the rotor 10 of

bearing

8,9.

International publication WO99/65758 discloses a kind of brushless electric machine, and wherein, bearing of the common use of rotor and worm screw is to reduce the length of motor.

But in this structure, the axial location of rotor will be moved along with the variation of worm screw load, thereby can cause producing vibration or the such problem of performance change.In addition, need under the controlled condition of strictness, assemble,, and must assemble rotor and stator individually in order to avoid iron powder etc. are attached to the rotor that is provided with the permanent magnet that is used for rotating drive.Thereby produced the problem of assembling the convenience variation and having increased the assembly technology step.In addition, could detect motor after the assembling of Worm gear mechanism and brushless electric machine is finished, that is to say, motor can not detect its performance etc. when separate state.

In electrically powered steering apparatus using same shown in Figure 16, be provided with aforesaid flange 6 (dividing plate) in the boundary space between Worm gear mechanism and brushless electric machine and be installed in the bearing 8 of the radially inner peripheral of flange (dividing plate).

Therefore, if the lubricating grease in the Worm gear mechanism or just may enter brushless electric machine such as the such foreign matter of iron powder, aforesaid flange 6 (dividing plate) and bearing 8 formed sealings will prevent that foreign matter and lubricating grease from entering.

In addition, if want to reduce the size of brushless electric machine, can adopt the structure of the installation site of aforesaid bearing 8 of cancellation or change bearing 8.

But if cancelled bearing 8 or changed the position of bearing 8, the border region between Worm gear mechanism and the brushless electric machine will become unlimited, and Worm gear mechanism and brushless electric machine will be interconnected.Therefore, the such foreign matter of lubricating grease in the Worm gear mechanism or iron powder just has the danger that enters brushless electric machine.

In addition, from the size that reduces electrically powered steering apparatus using same, reduce noise of motor or be beneficial to the viewpoint of motor radiating, wish to adopt the brushless electric machine of making by resin mold.

Yet though the used drive motors of the ventilation unit of the household electrical appliance motor of molded formation normally, electrically powered steering apparatus using same does not also have the motor of molded formation at present.

With reference to Figure 17 A and 17B the motor of the molded formation that is used to drive ventilation unit is described (the 2nd page and Fig. 1,2,9 and 10 for example, examining open NO.10-271720 referring to Japanese patent application) below.Figure 17 A shows the motor 200 of the ventilation unit of looking from oblique upper, and Figure 17 B is the cutaway view of motor 200.In Figure 17 A and 17B, stator 201 is by mode molded form of synthetic resin 204 with coating stator core 202 and coil 203.In addition, permanent magnet 209 is fixed on axle 211 and forms on the rotor 208 of one.They are installed in the stator 201, and axle 211 is supported by the bearing 214 that is installed in the bearing 206 in the bearing pedestal 205 and be installed in the bearing pedestal 213.In this bearing arrangement, though be difficult to make stator 201 and rotor 208 to obtain higher axiality, its being applied in of motor as the household electrical appliance ventilation unit does not need the required precision higher than necessary axiality on the axiality.

Make by molded if having the brushless electric machine of the electrically powered steering apparatus using same of structure like the electric machinery with above-mentioned ventilation unit, will produce following problem.For the motor of electrically powered steering apparatus using same, when with vehicle drive during to the parking stall towards a direction and then when rotating steering wheel to another way, perhaps when urgent quick rotation steering wheel constantly, need motor forward and rotate backward with bigger moment.Therefore, require to have very high axiality, to suppress noise and torque fluctuations.

In rotor is provided with bearing support structure by the resin molded bearing bore that forms, because state changes in the molding process, shrinkage is different with the difference of resin molded direction, weld or other very difficult usually precision that improves bearing bore.Under the lower situation of axiality lower in the bearing bore precision or it and stator inner peripheral, column stator and the axiality of inserting the column rotor that wherein rotates are reduced.Therefore, will increase pulsation moment, increase moment of friction and increase the noise of motor.The increase of pulsation moment can be delivered to the driver on hand, thereby he is felt under the weather, and the moment of friction increase not only can be lost power of motor, and the responding ability to motor control signal is reduced.

Summary of the invention

The present invention makes at above-mentioned situation.First purpose of the present invention provides a kind of electrically powered steering apparatus using same, wherein, can reduce the length of this device under the situation that does not reduce this device performance and assembling convenience.

For realizing above-mentioned first purpose, first invention according to the application, a kind of electrically powered steering apparatus using same is provided, it can be according to the steering moment that is applied on the steering wheel, produce an assisted diversion moment by a brushless electric machine, and with the output shaft of this assisted diversion transmission of torque to a steering mechanism, slow down by decelerator simultaneously, it comprises:

The element to be detected that a rotor, a column permanent magnet and that is used for rotating drive are used to detect the corner of described rotor is installed in described rotor;

A column stator relative with described rotor, a lamination core that is wound with coil, the checkout gear and that is used for detecting by described element to be detected the corner of described rotor are used for the terminals of connecting coil by resin molded this stator that is formed on; And

At least one bearing, described bearing are used for the described rotor of rotatably support, and are arranged on the radially inner side of described stator and between the described permanent magnet and described element to be detected that is used for rotating drive.

As mentioned above, according to first invention, at least one bearing that is used for the rotatably support rotor is arranged on the radially inner side of stator, and between permanent magnet that is used for rotating drive and element to be detected.In other words, bearing is arranged on one and is used to prevent the misoperation between checkout gear and the coil and in the space that is provided with.This just can reduce the length of rotor and the length of brushless electric machine.

In addition, being arranged on one at bearing is used to prevent the misoperation between checkout gear and the coil and in the space that is provided with and under the bearing situation about being made by magnetisable material, bearing will form a magnetic circuit that is used to limit from the magnetic flux of coil, thereby the influence that is produced by coil and act on the magnetic flux on the checkout gear is diminished, and can improve the sensitivity of checkout gear.

In the electrically powered steering apparatus using same of first invention, preferably, the internal diameter of described stator changes vertically step by step.According to this optimal way, the internal diameter of described stator changes vertically step by step.In other words, the internal diameter of stator is bigger in its open side, and becomes less diameter step by step from bigger diameter to the inside.Therefore, after resin molded and sclerosis, just the core metal of metal pattern can be extracted and mounting board does not take place, and can successfully mould be removed.

The internal diameter of described stator changes vertically step by step, and just the internal diameter of stator greatly also becomes less diameter from bigger diameter to the inside step by step in its open side.Therefore, the rotor that bearing is housed on it can insert from the open side with maximum gauge, and has improved the convenience of assembling.

Therefore, in assembling process, can after the assembling of finishing brushless electric machine separately, again brushless electric machine be installed on the Worm gear mechanism.Therefore, can not reduce the convenience of assembling, and can under separate state, detect performance of brushless electric machine etc.

In addition, in the electrically powered steering apparatus using same of first invention, preferably, described stator comprises that integratedly a cable connects terminals.According to this optimal way, this stator comprises that integratedly a cable connects terminals.Promptly, because being used for the cable of the terminals that link to each other with coil and the terminals of the signal that is used to export checkout gear is connected terminals (connector) and is integrally formed at stator, therefore the desired operation that comes stube cable by welding or alternate manner can be dispensed usually, thereby the number of the step in component number and the assembling process can be reduced.

In addition, in the electrically powered steering apparatus using same of first invention, preferably, described element to be detected is installed on the end of the rotor relative with motor outlet side end.According to this optimal way, on the end that element to be detected is arranged on the rotor relative with motor outlet side end, thereby eliminated gear box is connected terminals with cable interference portion, and can simplify shape and improve the dustproof and waterproof performance, thereby can prevent that in the process of assembling motor separately iron powder etc. from entering inside.

In addition, in the electrically powered steering apparatus using same of first invention, preferably, described stator is provided with one on its outer surface and is used for described brushless electric machine is installed to flange on the described decelerator, and flange is arranged near the position along the middle part of the longitudinal axis of stator.According to this optimal way, stator is provided with a flange to decelerator to be installed on its outer surface.Therefore, brushless electric machine can be installed to by the flange of stator on the decelerator, therefore can dispense the common motor housing that is made of metal and the mounting flange of this shell.Therefore can reduce the number of the step in component number and the assembling process, and reduce manufacturing cost.In addition,, can reduce the distance between motor center of gravity and the flange, thereby reduce owing to vibration and other reason are created in power in the flange by flange being arranged near position along the middle part of stator shaft orientation.Therefore, the required intensity of flange can be reduced, just its weight and size can be reduced.

For realizing aforesaid first purpose, second invention according to the application, a kind of electrically powered steering apparatus using same is provided, it can be according to the steering moment that is applied on the steering wheel, produce an assisted diversion moment by a brushless electric machine, and with the output shaft of this assisted diversion transmission of torque to a steering mechanism, slow down by one speed reducer simultaneously, it comprises:

The element to be detected that a rotor, a column permanent magnet and that is used for rotating drive are used to detect the corner of described rotor is installed in this rotor;

Two are bearing in the bearing that is used for the described rotor of rotatably support on the described stator.

As mentioned above, according to second invention, because two bearings that are used for the rotatably support rotor are bearing in stator, so the lamination core of stator and the radial clearance between the rotor can strictly keep constant.Therefore, the transmission that can reduce to vibrate etc., with guarantee have stable performance if having time, keep quite simultaneously.

In addition, because stator forms by resin is molded integratedly in the mode that covers coil, lamination core, checkout gear and terminals, therefore, it has also played the effect of the common motor housing that is made of metal.Therefore, brushless electric machine can be installed on the decelerator by stator, and can dispense the common electric machine shell that is made of metal.Therefore can reduce the number of the step in component number and the assembling process, and reduce manufacturing cost.

In the electrically powered steering apparatus using same of second invention, preferably, described stator has the wall of a sealing, an opening of the side that the sealing of the wall of this sealing is relative with decelerator, and keep in described two bearings one.According to this optimal way, stator has the wall of a sealing, the opening of the side that the sealing of the wall of this sealing is relative with decelerator, and keep in two bearings one.Therefore, can be easily with a Bearing Installation on the wall of this sealing.

In addition, in the electrically powered steering apparatus using same of second invention, preferably, the another one in described two bearings is arranged on the radially inner side of described stator, and between the described permanent magnet and described element to be detected that is used for rotating drive.According to this optimal way, the another one in two bearings is arranged on the radially inner side of stator, and between permanent magnet that is used for rotating drive and element to be detected.In other words, bearing is arranged on one and is used to prevent the misoperation between checkout gear and the coil and in the space that is provided with.This just can reduce the length of rotor and the length of brushless electric machine.

In addition, being arranged on one at bearing is used to prevent the misoperation between checkout gear and the coil and in the space that is provided with and under the bearing situation about being made by magnetisable material, bearing will form a magnetic circuit that is used for the magnetic flux that limiting coil produces, thereby the influence that is produced by coil and act on the magnetic flux on the checkout gear is diminished, and can improve the sensitivity of checkout gear.

In the electrically powered steering apparatus using same of second invention, preferably, the internal diameter of described stator changes vertically step by step.According to this optimal way, the internal diameter of described stator changes vertically step by step.In other words, the internal diameter of stator is bigger in its open side, and becomes less diameter step by step from bigger diameter to the inside.Therefore, after resin molded and sclerosis, just the core metal of metal pattern can be extracted and mounting board does not take place, and can successfully mould be removed.

Therefore, in assembling process, can after the assembling of finishing brushless electric machine separately, again brushless electric machine be installed on the decelerator.Therefore, can not reduce the convenience of assembling, and can under separate state, detect performance of brushless electric machine etc.

In addition, in the electrically powered steering apparatus using same of second invention, preferably, described stator comprises that integratedly a cable connects terminals.According to this optimal way, this stator one comprises that a cable connects terminals.Promptly, because be used for terminals that link to each other with coil and be used for the cables of terminals of exporting the signal of checkout gear and be connected terminals (connector) and be integrally formed at stator, therefore can dispense usually and desiredly come the operation of stube cable, thereby reduce the number of the step in component number and the assembling process by welding or alternate manner.

In addition, in the electrically powered steering apparatus using same of second invention, preferably, described stator has a flange to described decelerator to be installed on its outer surface, and this flange is arranged on the position of edge near the middle part of the longitudinal axis of stator.According to this optimal way, this stator has a flange that is installed on the decelerator on its outer surface.Therefore, brushless electric machine can be installed to by the flange of stator on the decelerator, therefore can dispense the common motor housing that is made of metal and the mounting flange of this shell.Therefore can reduce the number of the step in component number and the assembling process, and reduce manufacturing cost.In addition,, can reduce the distance between motor center of gravity and the flange, thereby reduce owing to vibration and other reason are created in power in the flange by flange being arranged near position along the middle part of stator shaft orientation.Therefore, the required intensity of flange can be reduced, just its weight and size can be reduced.

In addition, in the electrically powered steering apparatus using same of second invention, preferably, described element to be detected is installed on the end of the rotor relative with motor outlet side end.According to this optimal way, on the end that element to be detected is arranged on the rotor relative with motor outlet side end, thereby eliminated gear box is connected terminals with cable interference portion, and can simplify shape and improve the dustproof and waterproof performance, thereby can prevent that in the process of assembling motor separately iron powder etc. from entering inside.

Second purpose of the present invention provides a kind of electrically powered steering apparatus using same, and it can avoid the inside that enters into motor such as the such foreign matter of iron powder and the lubricating grease in the decelerator reliably.

For realizing above-mentioned second purpose, the 3rd invention according to the application, a kind of electrically powered steering apparatus using same is provided, it can be according to the steering moment that is applied on the steering wheel, produce an assisted diversion moment by a motor, and with the output shaft of this assisted diversion transmission of torque to a steering mechanism, slow down by one speed reducer simultaneously, this device has one and is used for protective element that the border region between described decelerator and the described motor is protected, this protective element is installed on the rotor of described motor rotating with rotor, and leaves a predetermined little gap between the static part of this protective element and described motor or described decelerator.

As mentioned above, according to the 3rd invention, this device is provided with one and is used for protective element that the border region between decelerator and the motor is protected, this protective element is installed on the rotor of motor, rotating with rotor, and one and the static part of motor or decelerator between leave predetermined little gap.Therefore, even may enter in the motor such as iron powder such foreign matter and lubricating grease, protective element can prevent reliably that also foreign matter and lubricating grease from entering wherein.

In the electrically powered steering apparatus using same of the 3rd invention, preferably, the static part of described protective element and described motor or described decelerator cooperatively interacts and form a predetermined little gap with labyrinth effect between it.According to this optimal way, because cooperatively interacting, the stationary part of protective element and motor or decelerator between it, forms a predetermined little gap with labyrinth effect, therefore, can prevent entering of foreign matter and lubricating grease more reliably.

In addition, in the electrically powered steering apparatus using same of the 3rd invention, preferably, described motor is a brushless electric machine, the element to be detected that the column permanent magnet and being used to that is used for rotating drive detects the corner of described rotor is installed in described rotor, and this device has column stator and two bearings that are used for rotatably support described rotor relative with described rotor, one is wound with the lamination core of a coil, be used for detecting the checkout gear of the corner of described rotor by described element to be detected, one terminals and that are used for connecting coil cover described coil, described lamination core, the column resin enclosure part of described checkout gear and described terminals is formed in the described stator by resin molded, and described bearing is bearing on the described column resin enclosure part.The checkout gear and the element to be detected that are used for the detection rotor corner not only can be Hall integrated circuit and permanent magnet, and can be phase splitter (resolver) and induction code device (inductcoder).According to this optimal way, because two bearings that are used for the rotatably support rotor are bearing in column resin enclosure part, so the lamination core of stator and the radial clearance between the rotor can strictly keep constant.Therefore, the transmission that can reduce to vibrate etc., with guarantee have stable performance if having time, keep quite simultaneously.

In addition, according to this optimal way since column resin enclosure part by resin to cover molded integratedly the forming of mode of coil, lamination core, checkout gear and terminals, therefore, it has also played the effect of the common electric machine shell that is made of metal.Therefore, brushless electric machine can partly be installed on the decelerator by the column resin enclosure, and can dispense the common motor housing that is made of metal.Therefore can reduce the number of the step in component number and the assembling process, and reduce manufacturing cost.

In the electrically powered steering apparatus using same of the 3rd invention, preferably, described column resin enclosure partly has the wall of a sealing, the opening of the side that the sealing of the wall of this sealing is relative with decelerator, and keep in described two bearings one.According to this optimal way, the column resin enclosure partly has the wall of sealing, the opening of the side that the sealing of the wall of this sealing is relative with decelerator, and keep in two bearings one.Therefore, can be easily with a Bearing Installation on the wall of this sealing.

In addition, in the electrically powered steering apparatus using same of the 3rd invention, preferably, the another one in described two bearings is arranged on the radially inner side of described stator, and between the described permanent magnet and described element to be detected that is used for rotating drive.According to this optimal way, the another one in two bearings is arranged on the radially inner side of stator, and between permanent magnet that is used for rotating drive and element to be detected.In other words, bearing is arranged on one and is used to prevent the misoperation between checkout gear and the coil and in the space that is provided with.This just can reduce the length of rotor and the length of brushless electric machine.In addition, in the preferred embodiment, being arranged on one at bearing is used to prevent the misoperation between checkout gear and the coil and in the space that is provided with and under the bearing situation about being made by magnetisable material, bearing will form a magnetic circuit that is used for the magnetic flux that limiting coil produces, thereby the influence that is produced by coil and act on the magnetic flux on the checkout gear is diminished, and can improve the sensitivity of checkout gear.

In the electrically powered steering apparatus using same of the 3rd invention, preferably, the internal diameter of described stator changes vertically step by step.According to this optimal way, the internal diameter of described stator changes vertically step by step.In other words, the internal diameter of stator is bigger in its open side, and becomes less diameter step by step from bigger diameter to the inside.Therefore, after resin molded and sclerosis, just the core metal of metal pattern can be extracted and mounting board does not take place, and can successfully mould be removed.The internal diameter of described stator changes vertically step by step, and just the internal diameter of stator greatly also becomes less diameter from bigger diameter to the inside step by step in its open side.Therefore, the rotor that bearing is housed on it can insert from the open side with maximum gauge, and has improved the convenience of assembling.

In addition, in the electrically powered steering apparatus using same of the 3rd invention, preferably, described stator comprises that integratedly a cable connects terminals.According to this optimal way, this stator comprises that integratedly a cable connects terminals.Promptly, because the cable that is used for terminals that link to each other with coil and is used as the terminals of the signal of exporting checkout gear is connected terminals (connector) and is integrally formed at stator, therefore can dispense usually and desiredly come the operation of stube cable, thereby reduce the number of the step in component number and the assembling process by welding or alternate manner.

In addition, in the electrically powered steering apparatus using same of the 3rd invention, preferably, described column resin enclosure part has a flange to described decelerator to be installed on its outer surface.According to this optimal way, column resin enclosure part has a flange to decelerator to be installed on its outer surface.Therefore, brushless electric machine can be installed on the decelerator by the flange of column resin enclosure part, therefore can dispense usually desired motor housing that is made of metal and the mounting flange that is used for this shell.Therefore can reduce the number of the processing step in component number and the assembling process, and reduce manufacturing cost.In addition,, can reduce the motor center of gravity and be used to install distance between the flange of motor, thereby reduce owing to vibration and other reason are created in power in the flange by flange being arranged on along position near the middle part of stator shaft orientation.Therefore, the required intensity of flange can be reduced, just its weight and size can be reduced.

As mentioned above, the 3rd purpose of the present invention provides a kind of brushless electric machine that is used for electrically powered steering apparatus using same, wherein, can improve the axiality at the center of the internal diameter of the molded stator that forms and rotor bearing, strengthen heat-sinking capability, reduce noise, keep good steering wheel operation feeling simultaneously.

According to being used to realize the 4th invention of the 3rd purpose of the application, a kind of brushless electric machine is provided, it comprises that a column rotor and is by resin molded all-in-one-piece column stator, described rotor inserts and is received in the described stator, wherein, at least one bearing element that is used for fixing the bearing that is used to support described rotor is arranged on described stator, and described bearing element and described stator form by resin molded.

In the brushless electric machine of the 4th invention, for improving the axiality of described rotor and described stator, preferably, on described bearing element, be provided with projection, in internal circumferential, the exterior circumferential of the stator core that constitutes described stator, be provided with notch near the end face of internal circumferential or near on the end face of exterior circumferential, described projection and described notch cooperatively interact to improve the axiality of described rotor and described stator.

In addition, preferably, described notch is arranged on the position that makes by the variation minimum of the magnetic flux of the caused described stator core of described notch.In addition, preferably, described notch is arranged on the position that makes by the variation minimum of the magnetic flux of the caused described stator core of described notch, and the position of described notch is positioned on the center line of a tooth of described stator core.

In the brushless electric machine of the 4th invention, for improving the axiality of described rotor and described stator, preferably, described bearing element has minimum internal diameter, the external diameter that can allow simultaneously to constitute the stator core of described stator is engaged in wherein, and described bearing element and described stator cooperatively interact.

In addition, in the brushless electric machine of the 4th invention, preferably, described bearing element is made by rigid material.

Preferably, described rigid material is iron material, aluminum or resin-based materials.Preferably, described brushless electric machine is used for electrically powered steering apparatus using same.

Description of drawings

Fig. 1 is the longitudinal sectional view that the electrically powered steering apparatus using same of first embodiment of the invention is shown;

Fig. 2 is the longitudinal sectional view that the electrically powered steering apparatus using same of second embodiment of the invention is shown;

Fig. 3 is the longitudinal sectional view that the electrically powered steering apparatus using same of third embodiment of the invention is shown;

Fig. 4 is the longitudinal sectional view that the electrically powered steering apparatus using same of fourth embodiment of the invention is shown;

Fig. 5 is the longitudinal sectional view that the electrically powered steering apparatus using same of fifth embodiment of the invention is shown;

Fig. 6 is the longitudinal sectional view that the electrically powered steering apparatus using same of sixth embodiment of the invention is shown;

Fig. 7 is the longitudinal sectional view that the electrically powered steering apparatus using same of seventh embodiment of the invention is shown;

Fig. 8 is the longitudinal sectional view that the electrically powered steering apparatus using same of eighth embodiment of the invention is shown;

Fig. 9 is a perspective view, and it is illustrated among the 8th embodiment stator core and rear side bearing element and how installs;

Figure 10 A-10C illustrates rear side bearing element and the stator core among the 8th embodiment;

Figure 11 A-11C illustrates front side bearing element and the stator core among the 8th embodiment;

Figure 12 A-12C illustrates the rear side bearing element and the stator core of first modification of the 8th embodiment;

Figure 13 A-13C illustrates the front side bearing element and the stator core of first modification of the 8th embodiment;

Figure 14 A-14C illustrates the rear side bearing element and the stator core of another modification of the 8th embodiment;

Figure 15 A-15C illustrates the front side bearing element and the stator core of described another modification of the 8th embodiment;

Figure 16 is the longitudinal sectional view of common electric transfer; And

Figure 17 A and 17B illustrate the common electric machine that is used for ventilation unit of molded formation.

Embodiment

Below in conjunction with accompanying drawing the electrically powered steering apparatus using same as the embodiment of the invention is described.

Fig. 1 is the longitudinal sectional view that the electrically powered steering apparatus using same of first embodiment of the invention is shown.

As shown in Figure 1, an output shaft 1 links to each other with a power shaft (not shown) by a torsion bar (not shown), and power shaft links to each other with a steering wheel (not shown).The worm gear 2 of one worm gear reducer mechanism is fixedly mounted on the output shaft 1.

The worm screw 5 that is rotatably supported in the gear box 3 by bearing 4a and 4b engages with worm gear 2.

Gear box 3 links to each other with a motor housing 7 of brushless electric machine.The rotor 10 of brushless electric machine is connected by a spline fitted part 11 with worm screw 5, thereby they can be in axial motions but can not relatively rotate with respect to each other.

Radially outer at rotor 10 is circumferential, and relatively to be provided with a permanent magnet 12 that is used for the column of rotating drive with a lamination core 16, this set-up mode will hereinafter be described.In addition, also be provided with the annular permanent magnet 13 (element to be detected) that is used for sensing (sense).

The radially inner side of motor housing 7 is provided with the stator 30 of a column.Stator 30 is wound with the lamination core 16 of coil 15 by resin and, one detects the magnetic field of the permanent magnet 13 (element to be detected) that is used for sensing so that the Hall integrated circuit 17 (checkout gear) of the corner of detection rotor 10, one is used to install the circuit board 18 of Hall integrated circuit 17, one is used for the terminals (bus) 19 of a connecting coil 15 and is used for terminals that link to each other with coil 15 and is connected terminals (connector) 31 as the cable of the terminals of the signal of output Hall integrated circuit 17 (checkout gear) molded integratedly.

Cable connects terminals (connector) 31 can be by making with molded middle resin identical materials of using or different materials.

In this embodiment, the bearing 8 that is used for the worm screw side part of rotatably support rotor 10 is arranged on the radially inner side of stator 30 and is positioned at the permanent magnet 12 that is used for rotating drive and between the permanent magnet 13 that is used for sensing (element to be detected).

More particularly, bearing 8 is installed in radially inner side by the resin molded stator that forms 30 by a columnar shaft bearing 34.Alternatively, bearing 8 can not use bearing pedestal 34 and be directly installed on the radially inner side of stator 30.

One bearing 9 that is used for supporting rotor 10 sidepiece relative with the worm screw side is arranged on motor housing 7.

Bearing 8 is arranged in the space that is used to prevent the misoperation between Hall integrated circuit 17 (checkout gear) and the coil 15 and is provided with.This just can reduce the length of rotor 10 and the length of brushless electric machine.

In addition, in bearing 8 is arranged on the space that is used to prevent the misoperation between Hall integrated circuit 17 (checkout gear) and the coil 15 and is provided with and under bearing 8 situation about making by magnetisable material, bearing 8 will form a magnetic circuit that is used to limit from the magnetic flux of coil 15, thereby influence that produced by coil 15 and that act on the magnetic flux on the Hall integrated circuit 17 (checkout gear) is diminished, and can improve the sensitivity of Hall integrated circuit 17 (checkout gear).Checkout gear is not limited to Hall integrated circuit and permanent magnet with the element to be detected that is used for the corner of detection rotor 10, also can adopt phase splitter or induction code device etc.

Internal diameter by the resin molded stator that forms 30 changes vertically step by step.Specifically, the internal diameter of stator 30 is bigger in its open side, and becomes less diameter step by step from bigger diameter to the inside.

Therefore, after resin molded and sclerosis, just the core metal of metal pattern can be extracted and mounting board does not take place, and can successfully mould be removed.

Because the internal diameter of stator 30 greatly also becomes less diameter from bigger diameter to the inside step by step in its open side, therefore, the rotor 10 that bearing 8 is housed on it can insert from the open side with maximum gauge, and has improved the convenience of assembling.

In addition, because in by the resin molded stator that forms 30, it is molded integratedly that the cable that is used for the terminals that link to each other with coil 15 and the terminals of the signal that is used to export Hall integrated circuit (checkout gear) 17 is connected terminals (connector) 31 usefulness resins, therefore the desired operation that comes stube cable by welding or alternate manner can be dispensed usually, thereby the number of the step in component number and the assembling process can be reduced.

Fig. 2 is the longitudinal sectional view of the electrically powered steering apparatus using same of second embodiment of the invention.

As shown in Figure 2, output shaft 1 links to each other with the power shaft (not shown) by the torque arm (not shown), and power shaft links to each other with the steering wheel (not shown).The worm gear 2 of worm gear reducer mechanism (decelerator) is fixedly mounted on the output shaft 1.

The worm screw 5 that is rotatably supported in the gear box 3 by bearing 4 grades is meshed with worm gear 2.

The rotor 10 of brushless electric machine is connected by a spline fitted part 11 with worm screw 5, thereby they can be in axial motions but can not relatively rotate with respect to each other.

Radially outer at rotor 10 is circumferential, relatively is provided with a permanent magnet 12 that is used for the column of rotating drive with a lamination core 15, and this set-up mode will hereinafter be described.In addition, also be provided with an annular permanent magnet 13 (element to be detected) that is used for sensing.

The radially inner side of motor housing 7 is provided with the stator 30 of a column.Stator 30 is wound with the lamination core 16 of coil 15 by resin and, one detects the magnetic field of the permanent magnet (element to be detected) 13 that is used for sensing so that the Hall integrated circuit 17 (checkout gear) of the corner of detection rotor 10, one is used to install the circuit board 18 of Hall integrated circuit 17, one is used for the terminals (bus) 19 of connecting coil 15 and as the terminals that link to each other with coil 15 with to be connected terminals (connector) 31 as the cable of the terminals of the signal of output Hall integrated circuit 17 (checkout gear) molded integratedly.Stator 30 has to be integrally formed at and is used on its outer surface brushless electric machine is installed to flange 33 on the Worm gear mechanism (decelerator).Checkout gear is not limited to Hall integrated circuit and permanent magnet with the element to be detected that is used for the corner of detection rotor 10, also can adopt phase splitter or induction code device etc.

Cable connects terminals (connector) 31 can be by making with molded middle resin identical materials of using or different materials.It is available, and to be generally used for the PBT or the PA6 of connector molded, integrally molded with stator 30 then.

Because stator 30 is by mode molded form of resin with covering coil 15, lamination core 16, Hall integrated circuit (checkout gear) 17, circuit board 18 and terminals (bus) 19, therefore, it has also played the effect of the common motor housing that is made of metal (7).

Therefore, brushless electric machine can be installed on the Worm gear mechanism by the flange 33 of stator 30, and can dispense the common motor housing that is made of metal (7) and be used for the mounting flange of this shell.Therefore can reduce the number of the step in component number and the assembling process, and reduce manufacturing cost.

In this embodiment, a bearing 8 that is used for the worm screw side part of rotatably support rotor 10 is arranged on the radially inner side of stator 30 and is positioned at the permanent magnet 12 that is used for rotating drive and between the permanent magnet 13 that is used for sensing (element to be detected).

Stator 30 has the wall 35 of sealing, the opening of the side that wall 35 sealing is relative with the worm screw side, and keep a bearing 9 that is used for rotatably support rotor 10.More specifically, bearing 9 is held in such a way, promptly is accommodated in the cavity 36 of closure wall 35.

As mentioned above, be bearing in stator 30 owing to be used for the

bearing

8 and 9 of rotatably support rotor 10, so the lamination core 16 of stator 30 and the radial clearance between the rotor 10 can strictly keep constant.Therefore, the transmission that can reduce to vibrate etc. is to guarantee stable performance all the time when keeping quite.

In addition, in bearing 8 is arranged on the space that is used to prevent the misoperation between Hall integrated circuit 17 (checkout gear) and the coil 15 and is provided with and under bearing 8 situation about making by magnetisable material, bearing 8 will form a magnetic circuit that is used to limit from the magnetic flux of coil 15, thereby influence that produced by coil 15 and that act on the magnetic flux on the Hall integrated circuit 17 (checkout gear) is diminished, and can improve the sensitivity of Hall integrated circuit 17 (checkout gear).

Internal diameter by the resin molded stator that forms 30 changes vertically step by step.Specifically, the internal diameter of stator 30 is bigger in its open side (worm screw side just), and (just relative with a worm screw side side) becomes less diameter step by step from bigger diameter to the inside.

Since the internal diameter of stator 30 in its open side (worm screw side) big and to the inside (side relative) with the worm screw side become less diameter step by step from bigger diameter, therefore, the rotor 10 that bearing 8 is housed on it can insert from the open side with maximum gauge, and has improved the convenience of assembling.

Fig. 3 is the longitudinal sectional view of the electrically powered steering apparatus using same of third embodiment of the invention.

In the 3rd embodiment, be provided with a column stator 30 that is formed from a resin.Stator 30 is wound with the lamination core 16 of coil 15 by resin and, one detects the magnetic field of the permanent magnet (element to be detected) 13 that is used for sensing so that the Hall integrated circuit 17 (checkout gear) of the corner of detection rotor 10, one is used to install the circuit board 18 of Hall integrated circuit 17, one be used for the terminals (bus) 19 of connecting coil 15 and the cable of the terminals that are used for linking to each other and the terminals of the signal that is used to export Hall integrated circuit 17 (checkout gear) with coil 15 to be connected terminals (connector) 31 molded integratedly.

Hall integrated circuit (checkout gear) 17, circuit board 18, terminals (bus) 19 are connected with cable in the heavy wall end that terminals (connector) 31 are arranged on the stator 30 relative with motor outlet side end.

One bearing 9 that is arranged in the sidepiece place of the stator 30 relative with motor outlet side end is installed in this thick wall part by a columnar shaft bearing 9a.

In addition, the permanent magnet (element to be detected) 13 that is used for sensing is installed in the end of the rotor 10 relative with motor outlet side end.Therefore, eliminated gear box 3 and be connected the interference portion of terminals 31 with cable, and can simplify shape and improve the dust and water protection performance, thereby can prevent that in assembling motor process iron powder etc. from entering inside.An end that is used for permanent magnet (element to be detected) 13 of sensing and rotor 10 is contained in a cavity 36 of the wall 35 of sealing.

In addition, the permanent magnet (element to be detected) 13 that is used for sensing is installed in the end of the rotor 10 relative with motor outlet side end.Therefore, eliminated gear box 3 and be connected the interference portion of terminals 31 with cable, and can simplify shape and improve the dust and water protection performance, thereby can prevent that in assembling motor process iron powder etc. from entering inside.

Stator 30 has the flange 33 that can be fixed on the decelerator on its outer surface.Therefore, brushless electric machine can be installed on the Worm gear mechanism by the flange 33 of stator 30, and can dispense common motor housing that is made of metal and the mounting flange that is used for this shell.Therefore, can reduce the number of element and in assembling process, reduce the number of step, and can reduce manufacturing cost.

In addition, by flange 33 is arranged on respect to stator 30 axially near on the position at center, can reduce the distance between motor center of gravity and the flange 33, thereby reduce owing to vibration and other reason are created in power in the flange 33.Therefore, the required intensity of flange 33 can be reduced, just its weight and size can be reduced.

Fig. 4 is the longitudinal sectional view of the electrically powered steering apparatus using same of fourth embodiment of the invention.

As shown in Figure 4, an output shaft 1 links to each other with a power shaft (not shown) by a torsion bar (not shown), and power shaft links to each other with a steering wheel (not shown).The worm gear 2 of one worm gear reducer mechanism (decelerator) is fixedly mounted on the output shaft 1.It is worm gear reducer mechanism that decelerator is not limited to.

One worm screw 5 that is rotatably supported in the gear box 3 by a bearing 4 grades engages with worm gear 2.

Radially outer at rotor 10 is circumferential, relatively is provided with a permanent magnet 12 that is used for the column of rotating drive with a lamination core 16, and this set-up mode will hereinafter be described.In addition, also be provided with the annular permanent magnet 13 (element to be detected) that is used for sensing.

The radially inner side of motor housing 7 is provided with the stator 30 of a column.Stator 30 forms by resin molded, it comprises that one is wound with the lamination core 16 of coil 15, one detects the magnetic field of the permanent magnet (element to be detected) 13 that is used for sensing so that the Hall integrated circuit 17 (checkout gear) of the corner of detection rotor 10, one is used to install the circuit board 18 of Hall integrated circuit 17, one is used for the terminals (bus) 19 of connecting coil 15, one is used for the terminals that link to each other with coil 15 are connected terminals (connector) 31 and a column with the cable of the terminals of the signal that is used to export Hall integrated circuit 17 (checkout gear) resin-case part 32, and this housing parts 32 covers coil 15, lamination core 16, Hall integrated circuit 17 (checkout gear), circuit board 18 and terminals (bus) 19.Column resin-case part 32 be provided with on its outer surface one with its all-in-one-piece flange 33, to be used for that brushless electric machine is installed to Worm gear mechanism (decelerator).Being used for the permanent magnet of sensing and Hall integrated circuit can replace by waiting as the phase splitter of checkout gear and element to be detected or induction code device.

Column resin-case part 32 is integrally molded to cover them with coil 15, lamination core 16, Hall integrated circuit 17, circuit board 18 and terminals (bus) 19.Therefore, this housing parts has also played the effect of the common motor housing that is made of metal (7).

Therefore, brushless electric machine can be installed on the Worm gear mechanism by the flange 33 of column resin-case part 32, and can dispense common motor housing that is made of metal (7) and mounting flange thereof.Therefore can reduce the number of the step in component number and the assembling process, thereby reduce manufacturing cost.

In the 4th embodiment, a bearing 8 that is used for the worm screw side part of rotatably support rotor 10 is arranged on the radially inner side of stator 30 and between permanent magnet 12 that is used for rotating drive and the permanent magnet 13 that is used for sensing.

Column resin-case part 32 has the wall 35 of sealing, the opening of the side that wall 35 sealing is relative with the worm screw side, and keep a bearing 9 that is used for rotatably support rotor 10.More specifically, bearing 9 is held in such a way, promptly is accommodated in the cavity 36 of closure wall 35.

As mentioned above, be bearing in column resin-case part 32 owing to be used for the

bearing

Bearing 8 is arranged in the space that is provided with in order to prevent the misoperation between Hall integrated circuit 17 and the coil 15.This just can reduce the length of rotor 10 and the length of brushless electric machine.

In addition, in bearing 8 is arranged on the space that is provided with in order to prevent the misoperation between Hall integrated circuit 17 and the coil 15 and under bearing 8 situation about making by magnetisable material, bearing 8 will form a magnetic circuit that is used to limit from the magnetic flux of coil 15, thereby influence that produced by coil 15 and that act on the magnetic flux on the Hall integrated circuit 17 is diminished, and can improve the sensitivity of Hall integrated circuit 17.

In addition, because in by the resin molded stator that forms 30, be used for terminals that link to each other with coil 15 and be used for a cable of terminals of exporting the signal of Hall integrated circuit (checkout gear) 17 that to be connected terminals (connector) 31 usefulness resins molded integratedly, therefore the desired operation that comes stube cable by welding or alternate manner can be dispensed usually, thereby the number of the step in component number and the assembling process can be reduced.

In the 4th embodiment, because bearing 8 is arranged on the radially inner side of stator 30 and between permanent magnet 12 that is used for rotating drive and the permanent magnet 13 that is used for sensing, therefore, the border region between Worm gear mechanism and the brushless electric machine is opened wide, and Worm gear mechanism and brushless electric machine are interconnected.Therefore, just exist the danger that enters brushless electric machine such as the such foreign matter of iron powder and lubricating grease.

To this, in the 4th embodiment, be provided with one and be used for protective element 40 that the border region between Worm gear mechanism and the brushless electric machine is protected.This protective element 40 is ring-type plectanes of being made by metal sheet, and it is installed on the rotor 10 of brushless electric machine, rotating with rotor 10, and leaves a little clearance G of being scheduled between the stator 30 of this protective element and brushless electric machine.

This little clearance G allows protective element 40 to rotate, and can realize the sealing function that prevents that foreign matter and lubricating grease from entering simultaneously.In this embodiment, though little clearance G is located between the stator 30 and protective element 40 as the stationary part of brushless electric machine, this little gap also can be located between the gear box 3 and protective element 40 as the stationary part of Worm gear mechanism.

As mentioned above, even may enter in the brushless electric machine such as iron powder such foreign matter and lubricating grease, protective element 40 can prevent reliably that also it from entering.

Fig. 5 is the longitudinal sectional view of the electrically powered steering apparatus using same of fifth embodiment of the invention.

As shown in Figure 5, in the 5th embodiment,, the radially inner side that is arranged on stator 30 and the bearing 8 between permanent magnet 12 that is used for rotating drive and the permanent magnet 13 that is used for sensing have been cancelled for reaching the purpose that further reduces size.

Still in the 5th embodiment, owing to removed bearing 8, so the border region between Worm gear mechanism and the brushless electric machine is opened wide, and Worm gear mechanism and brushless electric machine are interconnected.Therefore, just exist the danger that enters brushless electric machine such as the such foreign matter of iron powder and lubricating grease.

To this, in the 5th embodiment, be provided with one and be used for protective element 40 that the border region between Worm gear mechanism and the brushless electric machine is protected.This protective element 40 is ring-type plectanes of being made by metal sheet, and it is installed on the rotor 10 of brushless electric machine, rotating with rotor 10, and leaves a little clearance G of being scheduled between the stator 30 of this protective element and brushless electric machine.

As mentioned above, even may enter in the brushless electric machine such as iron powder such foreign matter and lubricating grease, it enters and also can be subjected to protective element 40 and stop reliably.

Fig. 6 is the longitudinal sectional view of the electrically powered steering apparatus using same of sixth embodiment of the invention.

As shown in Figure 6, in the 6th embodiment, a bearing 8 with and the similar mode of the 4th embodiment be arranged on the radially inner side of stator 30 and be used between the permanent magnet 13 of sensing at a permanent magnet 12 and that is used for rotating drive.

In the case, the border region between Worm gear mechanism and the brushless electric machine is opened wide, and Worm gear mechanism and brushless electric machine are interconnected.Therefore, just exist the danger that enters brushless electric machine such as the such foreign matter of iron powder and lubricating grease.

To this, in the 6th embodiment, be provided with one and be used for protective element 40 that the border region between Worm gear mechanism and the brushless electric machine is protected.

This protective element 40 is ring-type plectanes of being made by metal sheet, and it is installed on the rotor 10 of brushless electric machine, rotating with rotor 10, and leaves a little clearance G of being scheduled between the stator 30 of this protective element and brushless electric machine.Little clearance G allows protective element 40 to rotate, and can realize the sealing function that prevents that foreign matter and lubricating grease from entering simultaneously.

In addition, in the 6th embodiment, the marginal portion 41 of the circular protective element 40 of ring-type is towards axial bending.

By this structure, little clearance G not only is formed between the stator 30 and protective element 40 as the brushless electric machine stationary part, but also can be formed between the marginal portion 41 as the gear box 3 of Worm gear mechanism stationary part and protective element 40, therefore further improved the sealing property of little clearance G.

Therefore, in the 6th embodiment, even may enter in the brushless electric machine such as iron powder such foreign matter and lubricating grease, protective element 40 and marginal portion 41 thereof also can stop it to enter reliably.

In addition, because the marginal portion 41 of the circular protective element 40 of ring-type is towards axial bending, therefore can strengthen the sealing property of the little clearance G between gear box 3 and the marginal portion 41, particularly may enter under the situation of brushless electric machine when the such liquid of for example lubricating grease flows on rotor 10, marginal portion 41 can prevent effectively that lubricating grease etc. from entering.

Fig. 7 is the longitudinal sectional view of the electrically powered steering apparatus using same of seventh embodiment of the invention.

As shown in Figure 7, in the 7th embodiment, a bearing 8 with and the similar mode of the 4th and the 6th embodiment be arranged on the radially inner side of stator 30 and be used between the permanent magnet 13 of sensing at a permanent magnet 12 and that is used for rotating drive.

In the case, the border region between Worm gear mechanism and the brushless electric machine is also opened wide, and Worm gear mechanism and brushless electric machine are interconnected.Therefore, just exist the danger that enters brushless electric machine such as the such foreign matter of iron powder and lubricating grease.

To this, still in the 7th embodiment, be provided with one and be used for protective element 40 that the border region between Worm gear mechanism and the brushless electric machine is protected.

This protective element 40 is ring-type plectanes of being made by metal sheet, and it is installed on the rotor 10 of brushless electric machine, rotating with rotor 10, and leaves predetermined little clearance G between the stator 30 of this protective element and brushless electric machine.Little clearance G allows protective element 40 to rotate, and can realize the sealing function that prevents that foreign matter and lubricating grease from entering simultaneously.

In addition, in the 7th embodiment, the marginal portion 41 of the circular protective element 40 of ring-type is towards axial bending, and the gear box 3 of the stator 30 of the marginal portion 41 of protective element 40, brushless electric machine and Worm gear mechanism cooperatively interacts and forms a predetermined little clearance G with labyrinth effect betwixt.

Therefore, can further improve the sealing property of little clearance G, in this embodiment, even may enter in the brushless electric machine such as iron powder such foreign matter and lubricating grease, protective element 40 and marginal portion 41 thereof can prevent reliably that also it from entering.

In addition, because the marginal portion 41 of the circular protective element 40 of ring-type is towards axial bending, and the gear box 3 of the marginal portion 41 of protective element 40, the stator 30 of brushless electric machine and Worm gear mechanism cooperatively interacts and forms the little clearance G with labyrinth effect betwixt, therefore can further strengthen the sealing property of the little clearance G between gear box 3 and the marginal portion 41.Particularly may enter under the situation of brushless electric machine when the such liquid of for example lubricating grease flows on rotor 10, marginal portion 41 can prevent effectively that lubricating grease etc. from entering.

To describe the 8th embodiment in detail below.

In the 8th embodiment, the bearing of rotor is arranged on two positions, and is described below in conjunction with accompanying drawing 8,9,10A-10C and 11A-11C.Fig. 8 is the longitudinal sectional view of the brushless electric machine of electrically powered steering apparatus using same.

Brushless electric machine is done as a whole by brushless electric machine part (back will be called motor) 1 and one worm screw part 2 formations.For convenience of explanation, motor part 1 will be called as the front side near a side of worm screw part 2, and will be called as rear side away from a side of worm screw part 2.Motor part 1 mainly is made of a rotor 10 and stator 20.Rotor 10 is installed in this armature spindle column structure of circumferential lip-deep permanent magnet 12 outward for having an armature spindle 11 and that is positioned at the center.One permanent magnet 13 that is used to detect the transducer of turned position is fixed on armature spindle 11.Stator 20 column structure for constituting by stator core 21 and the coil 22 that twines around this stator core, and between stator core 21 and coil 22, be provided with insulation component 40.Stator 20 is contained in the shell 41.Rotor 10 can rotate under the situation in being inserted into stator 20.In the case, necessary supporting rotor axle 11 like this is so that it rotates under the situation that does not contact stator 20 reposefully.For this reason, in this embodiment, armature spindle 11 is bearing on the front side bearing element 15-1 by a cylindrical metal element 14-1a and bearing 14-1 in the front side, and is bearing on the rear side bearing element 15-2 by a bearing 14-2 at rear side.Front side and rear side bearing element 15-1 and 15-2 are respectively by stator 20 supportings.

These bearing elements 15-1 and 15-2 are set so that bearing element 14-1,14-1a and 14-2 are fixed on the stator 20 with the position relation correct with respect to stator, and each bearing element has one and is engaged on the stator 20 and is used for bearing 14-1,14-2 are bearing in the radially part of middle position by the part of stator 20 supportings and one.The center line of the center line of the cylinder of stator 20 and bearing 14-1 and 14-2 is adapted to coincidence on identical axis.In the bearing 14-1 of front side, but interior ring and shaped element 14-1a one constitute.

Fig. 9 is that rear side bearing element 15-2 and stator core 21 are shown is together the perspective view of how cooperatively interacting.

Figure 10 A is the front view of stator core 21, and Figure 10 B is the rearview of rear side bearing element 15-2, and Figure 10 C is the cutaway view through diameter of bearing element 15-2.Circumferential direction is provided with four notch 25-2-1,25-2-2,25-2-3 and 25-2-4 equally spacedly in the outside side face upper edge of stator core 21.Bearing element 15-2 is had by an annular section with stator core 21 that identical diameter and identical size and the flat annular section 15-2a that closely contacts with this annular section, outward extending vertically first stylolitic part 15-2b of the radially inner part from annular section 15-2a and one have the bottom and further the outward extending vertically second stylolitic part 15-2c one constitutes from the radially inner bottom side of the first stylolitic part 15-2b.First and second stylolitic parts are coaxial with stator core 21.Bearing 14-2 is bearing on the internal circumferential of the second stylolitic part 15-2c.Radial outside at the annular section 15-2a of bearing element 15-2 is provided with four protruding 15-2-1,15-2-2,15-2-3 and 15-2-4 that can match with four notch 25-2-1,25-2-2,25-2-3 and 25-2-4 of stator core 21 respectively, and bearing element 15-2 is in place at stator core 21 upper supports regularly by these parts are cooperatively interacted.Therefore, even dry the contraction taken place when molded stator core 21, the axiality of bearing 14-2 and stator core 21 also can fully be guaranteed.

In addition, bearing element 15-1 also comprises annular section 15-1a, the first stylolitic part 15-1b with intermediate diameters and the second stylolitic part 15-1c with minimum diameter that closely contact with the front side annular section of stator core 21, and all these parts are an integral body and coaxial mutually.The second stylolitic part 15-1c has a through hole and is supporting armature spindle 11 by bearing 14-1.Is how to be bearing in being described on the stator core 21 below in conjunction with Figure 11 A-11C to bearing element 15-1.

As mentioned above, bearing element 15-2 and stator core 21 are fixing according to correct position relation, even mould takes place by dry the contraction, the axiality of bearing 14-2 and stator core 21 also can fully be guaranteed.

Require the material of bearing element 15-1 and 15-2 to have certain rigidity, so that do not produce distortion when situation such as dry contraction takes place in molding process.Specifically, should use iron or aluminum.In addition, as long as its rigidity can be born high temperature and dry contraction the in the molding process, just there are not any problem in the bearing element 15-1, the 15-2 that apply the present invention to be made by the such resin-based materials of engineering plastics.The description of the material of this bearing element also is applicable to the material of bearing element 16-1,16-2,17-1 and the 17-2 that will be described hereinafter.

Notch is the factor that changes the shape of stator core 21, and they can influence the magnetic flux that passes stator core 21.For this reason, notch should be formed on the position of the magnetic flux that does not influence stator core 21 as far as possible.In Figure 10 A, the position (the position A among Figure 10 A just) that each notch 25-2-1,25-2-2,25-2-3 and 25-2-4 are formed on the exterior circumferential of stator core 21 of center line extend past of tooth of stator core 21 is located.If the centre position (the position B among Figure 10 A) that for example it is formed between the tooth is located, the width that will reduce magnetic circuit also can influence the magnetic flux of process significantly.In addition, if it is formed on position A, is positioned at inboard toothed portion and can keeps magnetic circuit, and its influence is maintained lesser extent.

With regard to the number of the stator core element 21 that is provided with notch, notch can only be arranged on so a plurality of stator core elements 21, that is, allow the projection of bearing element to be installed in the front side and the rear side of stator 20; Perhaps, notch can be formed on all stator core elements 21, a kind ofly is provided with notch and does not another kind ofly have two kinds of stator core elements of notch to produce inconvenience owing to existing avoiding in process of production.Be explained below in conjunction with Fig. 9, notch 25-2-2 can only be formed on the stator core element 21 of the some of wanting fitting projection 15-2-2, that is, notch can be arranged on a plurality of stator core elements by rear side shown in the solid line and front side; Perhaps, notch can be formed on all stator core elements 21 shown in the dotted line.This also is applicable to other notch 25-2-1,25-2-3 and 25-2-4 shown in Figure 9.The description of the number of the stator core that forms notch thereon is not only applicable to notch 25-2-1,25-2-2,25-2-3,25-1-1,25-1-2,25-1-3 among Fig. 9,10A-10C and the 11A-11C, and is applicable to Figure 12 A-12C that describes later and notch 26-2-1,26-2-2,26-2-3,26-1-1,26-1-2, the 26-1-3 among the 13A-13C.

Figure 11 A-11C shows front side bearing element 15-1, stator core element 21 and fit structure thereof.Shown in Figure 11 B, bearing element 15-1 has one for the following former thereby bigger portion C of cutting open that forms.For to the motor power supply, must cable be connected on the coil 22 of stator 20 by an a connector 31 and a bus 30, and formation is cut portion C open so that the space of lead-in cable to be provided.When protruding 15-1-1,15-1-2,15-1-3 and 15-1-4 cooperate respectively with notch 25-1-1,25-1-2,25-1-3 and 25-1-4, bearing element 15-1 and stator core 21 are with fixing according to correct position relation with the similar mode of rear side, even and dry the contraction taken place mould etc., also can keep the axiality of bearing 14-1 and stator core 21.

As mentioned above, effect for front side bearing element 15-1 and rear side bearing element 15-2, the center line of the center line of armature spindle 11 and stator 20 is positioned on the identical axis exactly, that is, the center line of the center line of rotor 10 and stator 20 is arranged on the identical axis exactly.As long as the position that stator core and bearing element can be correct relation is fixing, the number of projection and notch is not limited to four.

According to the 8th embodiment, if stator is molded forming, then because the effect of bearing element, stator and rotor are assembled into its center line and align coaxially, therefore, just can will be reduced to minimum degree, and can obtain to have the beneficial effect of good steering wheel operation feeling and low noise of motor owing to the not enough pulsation moment that cause of the axiality of rotor 10 and stator 20 and moment of friction.

Figure 12 A-12C and Figure 13 A-13C show the modification of the 8th embodiment.In this modification, the size of bearing element is dwindled, and is configured to can be installed on the internal circumferential of stator core.Figure 12 A-12C illustrates on the shape of rear side bearing element 16-2, the position that forms projection (being protruding 16-2-1,16-2-2,16-2-3) and the stator core 21 position with the corresponding notch of aforementioned projection (being notch 26-2-1,26-2-2,26-2-3).In addition, Figure 13 A-13C shows front side bearing element 16-1 and protruding 16-1-1,16-2-2,16-2-3.On stator core 21, be formed with and the corresponding notch 26-2-1 of aforementioned projection, 26-2-2,26-2-3.By utilizing bearing element according to this modification, also can with bearing 14-1 and 14-2 in correct fixed-site on stator 20, and can make rotor 10 and stator 20 have the height axiality.This can be avoided producing pulsation moment and the moment of friction that causes owing to axiality is lower, and obtains good steering wheel operation feeling and low noise of motor.

Though the notch shown in Figure 10 A-10C and the 11A-11C being formed on the modification that the 8th embodiment on the exterior circumferential and the notch shown in Figure 12 A-12C and the 13A-13C be formed on the internal circumferential is described, but the formation position of notch is not limited to the marginal position as exterior circumferential and internal circumferential, obviously, even with notch be formed on stator core 21 near the endface position of exterior circumferential or near on the endface position of internal circumferential so that match with the projection of bearing element, also can obtain same effect.

Figure 14 A-14C and Figure 15 A-15C show another modification of the 8th embodiment.In this modification, the position of not adopting notch and projection to fix between bearing element 17-1 and 17-2 and the stator 20 concerns.Because column stator 20, column rotor 10, armature spindle 11 and bearing 14-1 and 14-2 have circular cross section, therefore, when circumferential displacement takes place, can not reduce their axiality.Therefore, in the cross section of bearing element 17-1,17-2 is that the external diameter of the internal diameter of circle and bearing element 17-1,17-2 and stator core 21 equates to allow simultaneously under its together situation of cooperatively interacting, when bearing element 17-1,17-2 are coupled on the stator core 21, even circumferential displacement takes place for stator core 21 and bearing element 17-1 and 17-2, can not reduce the axiality of stator 20 and rotor 10 when molded yet.Under any circumstance all can realize the suitable axiality of stator 20 and rotor 10, therefore, also can obtain beneficial effect by this modification, as: the pulsation moment that causes owing to axiality is lower and moment of friction, good steering wheel operation feeling and lower noise of motor avoided.

Because front side and rear side bearing element can be selected independently of each other, therefore, the bearing element described in the 8th embodiment and the modification thereof can freely make up as front side and rear side bearing element and use.For example, can adopt rear side is that bearing element 15-2 shown in Figure 10 A-10C and front side are the combination of the bearing element 16-1 shown in Figure 13 A-13C.

Though in the 8th embodiment and modification thereof, used two bearing elements, also can only a bearing element be set as bearing element 15-2 at rear side, perhaps only a bearing element is set as bearing element 15-1 in the front side.In these cases, its for the contribution effect of axiality less than the situation that adopts two bearing elements, but much larger than the common structure of not using bearing element.

As described above, according to the brushless electric machine in the 8th embodiment and the modification thereof, improved the axiality of rotor and stator, improved heat dispersion simultaneously, and can advantageously provide a kind of electrically powered steering apparatus using same, wherein, even such as when with vehicle drive during to the parking stall towards a direction and then rotate steering wheel to another way or need motor with bigger moment forward and under the situation about rotating backward at urgent quick rotation steering wheel constantly, noise of motor is less, pulsation moment and moment of friction are lowered to lower level, and can obtain good steering wheel operation feeling.

Claims

1, a kind of electrically powered steering apparatus using same, it can produce an assisted diversion moment by a brushless electric machine according to the steering moment that is applied on the steering wheel, and with the output shaft of this assisted diversion transmission of torque to a steering mechanism, slows down by one speed reducer simultaneously, comprising:

A column stator relative with described rotor, a lamination core that is wound with coil, the checkout gear and that is used for detecting by described element to be detected the corner of described rotor are used to be connected the terminals of described coil by resin molded this stator that is formed on; And

At least one is used for the bearing of the described rotor of rotatably support, and described bearing is arranged on the radially inner side of described stator and between the described permanent magnet and described element to be detected that is used for rotating drive.

2, electrically powered steering apparatus using same according to claim 1 is characterized in that, the internal diameter of described stator changes vertically step by step.

3, electrically powered steering apparatus using same according to claim 1 is characterized in that, described stator comprises that integratedly a cable connects terminals.

4, electrically powered steering apparatus using same according to claim 1 is characterized in that, described element to be detected is arranged on the end of the described rotor relative with a motor outlet side end.

5, electrically powered steering apparatus using same according to claim 1 is characterized in that, described stator has a flange to described decelerator to be installed on its outer surface, and this flange is arranged near the position along the middle part of the longitudinal axis of stator.

6, a kind of electrically powered steering apparatus using same, it can produce an assisted diversion moment by a brushless electric machine according to the steering moment that is applied on the steering wheel, and with the output shaft of this assisted diversion transmission of torque to a steering mechanism, slows down by decelerator simultaneously, comprising:

A column stator relative with described rotor, a lamination core that is wound with a coil, the checkout gear and that is used for detecting by described element to be detected the corner of described rotor are used for the terminals of connecting coil by resin molded this stator that is formed on; And

7, electrically powered steering apparatus using same according to claim 6 is characterized in that, described stator has the wall of a sealing, an opening of the side that the sealing of the wall of this sealing is relative with described decelerator, and keep in described two bearings one.

8, electrically powered steering apparatus using same according to claim 6 is characterized in that, the another one in described two bearings is arranged on the radially inner side of described stator, and between the described permanent magnet and described element to be detected that is used for rotating drive.

9, electrically powered steering apparatus using same according to claim 6 is characterized in that, the internal diameter of described stator changes vertically step by step.

10, electrically powered steering apparatus using same according to claim 6 is characterized in that, described stator comprises that integratedly a cable connects terminals.

11, electrically powered steering apparatus using same according to claim 6 is characterized in that, described stator has a flange to described decelerator to be installed on its outer surface, and this flange is arranged near the position along the middle part of the longitudinal axis of stator.

12, electrically powered steering apparatus using same according to claim 6 is characterized in that, described element to be detected is arranged on the end of the described rotor relative with a motor outlet side end.

13, a kind of electrically powered steering apparatus using same, it can produce an assisted diversion moment by a motor according to the steering moment that is applied on the steering wheel, and with the shaft of this assisted diversion transmission of torque to a steering mechanism, slow down by one speed reducer simultaneously, this device comprises that one is used for protective element that the border region between described decelerator and the described motor is protected, this protective element is installed on the rotor of described motor rotating with this rotor, and leaves a predetermined little gap between the stationary part of this protective element and described motor or described decelerator.

14, electrically powered steering apparatus using same according to claim 13 is characterized in that, the stationary part of described protective element and described motor or described decelerator cooperatively interacts and form a predetermined little gap with labyrinth effect between it.

15, electrically powered steering apparatus using same according to claim 13 is characterized in that:

Described motor is a brushless electric machine;

The element to be detected that the one column permanent magnet and that is used for rotating drive is used to detect the corner of described rotor is fixed on described rotor:

The one lamination core that is wound with coil, the terminals and that are used for being used for by the checkout gear, that described element to be detected detects the corner of described rotor connecting coil cover the column resin enclosure part of described coil, described lamination core, described checkout gear and described terminals by the resin molded column stator relative with described rotor that be formed on; And

Two bearings that are used for the described rotor of rotatably support are bearing in described column resin enclosure part.

16, electrically powered steering apparatus using same according to claim 15 is characterized in that, described column resin enclosure partly has the wall of a sealing, an opening of the side that the sealing of the wall of this sealing is relative with described decelerator, and keep in described two bearings one.

17, electrically powered steering apparatus using same according to claim 16 is characterized in that, the another one in described two bearings is arranged on the radially inner side of described stator, and between the described permanent magnet and described element to be detected that is used for rotating drive.

18, electrically powered steering apparatus using same according to claim 15 is characterized in that, the internal diameter of described stator changes vertically step by step.

19, electrically powered steering apparatus using same according to claim 15 is characterized in that, described stator comprises that integratedly a cable connects terminals.

20, electrically powered steering apparatus using same according to claim 15 is characterized in that, described column resin enclosure part has a flange to described decelerator to be installed on its outer surface, and this flange is arranged near the position along the middle part of the longitudinal axis of stator.

21, electrically powered steering apparatus using same according to claim 15 is characterized in that, the open side of a spline coupling part is positioned at motor side.

22, a kind of brushless electric machine, comprise that a column rotor and is by the resin molded column stator that integrally forms, described rotor inserts and is received in the described stator, wherein, at least one bearing element that is used for fixing the bearing that is used to support described rotor is arranged on described stator, and described bearing element forms by resin molded and described stator.

23, brushless electric machine according to claim 22, it is characterized in that, on described bearing element, be provided with projection, in internal circumferential, the exterior circumferential of the stator core that constitutes described stator, be provided with notch near the end face of internal circumferential or near on the end face of exterior circumferential, described projection and described notch cooperatively interact to improve the axiality of described rotor and described stator.

24, brushless electric machine according to claim 23 is characterized in that, described notch is arranged on the position that makes by the variation minimum of the magnetic flux of the caused described stator core of described notch.

25, brushless electric machine according to claim 24 is characterized in that, the position of described notch is positioned on the center line of a tooth of described stator core.

26, brushless electric machine according to claim 22, it is characterized in that, described bearing element has minimum internal diameter, allow the external diameter of the stator core of the described stator of formation to be engaged in the described internal diameter simultaneously, and described bearing element and described stator cooperatively interact, to improve the axiality of described rotor and described stator.

27, brushless electric machine according to claim 22 is characterized in that, described bearing element is made by rigid material.

28, brushless electric machine according to claim 27 is characterized in that, described rigid material comprises iron material, aluminum or resin-based materials.

29, a kind of electrically powered steering apparatus using same wherein adopts a brushless electric machine according to claim 22.