Motor, driving system and braking system

Abstract

The invention relates to a motor, a driving system and a braking system, and the motor comprises a housing which is provided with an accommodation space; the stator assembly is positioned in the accommodating space and comprises a stator iron core and a winding; the rotor assembly is located in the containing space, and the rotor assembly is rotatably supported on the shell; the output component is fixedly connected with the rotor assembly; a stator assembly is radially located inside the rotor assembly, and an output member is radially located inside the stator assembly. The driving system is particularly suitable for a braking system, the motor of the driving system is of an outer rotor structure, and the output component is arranged on the axis, so that the torque provided under the same size and the same rotating speed is larger. In addition, based on the basic concept of the outer rotor, multiple functions are integrated on multiple components, multiple purposes are achieved, the number of parts is reduced on the basis that the needed functions are achieved, the size is reduced, and the cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of motors, and in particular to a motor and a driving system and a braking system comprising the motor. Background Art

[0002] In the braking system of the vehicle, a brake pedal is provided. When the vehicle needs to be decelerated, the driver can operate the wheel brakes in the braking system by stepping on the brake pedal to apply braking force to the wheels. With the development of braking technology, a wire control brake system has been developed to improve braking performance and driving comfort. In the wire control brake system, the driver does not directly operate the wheel brakes. When the driver steps on the brake pedal, the motion parameters of the brake pedal are collected, and the braking system determines the driver's braking intention based on the motion parameters of the brake pedal, and applies braking pressure to the wheel brakes through an electrically driven pressure source. The electrically driven pressure source includes an electric motor and a hydraulic cylinder. The motor and the piston of the hydraulic cylinder are connected through a motion conversion device to convert the rotational motion output by the motor into the linear motion of the piston.

[0003] At present, wire control brakes are developing rapidly in China. The drive unit is a brushless DC motor, and the motor is arranged as a solid shaft inner rotor structure, which is not conducive to the arrangement of the ball screw. Under the same master cylinder movement stroke, the solid shaft motor solution makes the entire module axial length 40-50mm longer, and the entire volume is larger, which is not conducive to compact design. At the same time, the inner rotor motor provides lower torque than the outer rotor motor under the same volume, and this low torque may not meet the demand. Summary of the invention

[0004] In order to solve one or more of the above technical problems at least to a certain extent, the present invention proposes the following technical solutions.

[0005] A motor, comprising:

[0006] A housing having a receiving space;

[0007] A stator assembly, the stator assembly is located in the accommodating space and includes a stator core and a winding;

[0008] a rotor assembly, the rotor assembly being located in the accommodation space and rotatably supported by the housing;

[0009] an output component, the output component being fixedly connected to the rotor assembly;

[0010] The stator assembly is located radially inside the rotor assembly, and the output component is located radially inside the stator assembly.

[0011] According to one aspect of the present invention, the rotor assembly includes a rotor frame and a plurality of permanent magnets arranged on the rotor frame, the rotor frame having an annular portion extending along the axial direction of the motor and provided with the permanent magnets, and a first bottom perpendicular to the axial direction, a plurality of openings distributed in the circumferential direction are arranged on the first bottom, and the openings are used to cooperate with an eddy current sensor to detect the rotational speed of the rotor frame.

[0012] According to one aspect of the present invention, the rotor skeleton further comprises a second bottom portion spaced apart from the first bottom portion in the axial direction, and a structure connected to the output component is disposed on the second bottom portion.

[0013] According to one aspect of the present invention, the present invention further comprises a magnetoresistive sensor accommodation portion for accommodating the magnetoresistive sensor between the housing and the rotor assembly in a radial direction.

[0014] The present invention also provides a driving system, comprising:

[0015] The motor according to above; and

[0016] The output component is accommodated in the hollow component, and the output component and the hollow component together form a motion conversion mechanism for converting the rotational motion of the output component into the linear motion of the hollow component.

[0017] According to one aspect of the present invention, the motor further comprises a stator supporting frame, the stator supporting frame having a cylindrical portion extending axially, and the cylindrical portion is radially located between the stator assembly and the hollow component, and the cylindrical portion is provided with an anti-rotation portion for preventing the hollow component from rotating.

[0018] According to one aspect of the present invention, the anti-rotation portion is a protrusion or a groove extending in the axial direction;

[0019] The hollow component is provided with a groove or a protrusion matched with the protrusion or the groove.

[0020] According to one aspect of the present invention, the stator support frame has an annular portion perpendicular to the axial direction, and a structure for mounting a magnetoresistive sensor is provided on the annular portion.

[0021] The present invention also provides a braking system, comprising:

[0022] According to the drive system above; and

[0023] A hydraulic cylinder, wherein the hollow component serves as a piston of the hydraulic cylinder.

[0024] According to one aspect of the present invention, a double-lip seal is provided at the end of the hollow component.

[0025] According to the above scheme, the present invention proposes a drive system particularly suitable for a brake system, wherein the motor of the drive system adopts an outer rotor structure, and the output component is arranged on the axis, so that the torque provided at the same speed under the same size is greater. In addition, based on the basic concept of the outer rotor, the present invention integrates multiple functions on multiple components, realizes multiple uses of one piece, reduces the number of parts, reduces the volume, and reduces the cost on the basis of realizing the required functions.

[0026] Other features and advantages of the present invention will be described in detail below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Exemplary embodiments of the present invention are described with reference to the accompanying drawings, in which:

[0028] Figure 1 An exploded view of the drive system of the present invention is shown.

[0029] Figure 2 A cross-sectional view of a drive system of the present invention is shown.

[0030] Figure 3 A perspective view of the drive system of the present invention is shown.

[0031] FIG. 4( a ) shows a cross-sectional view of the rotor skeleton of the motor of the present invention.

[0032] FIG. 4( b ) shows a three-dimensional view of the rotor skeleton of the motor of the present invention.

[0033] FIG. 4( c ) shows a top view of the rotor skeleton of the motor of the present invention.

[0034] Figure 5 A cross-sectional view showing a drive system of the present invention equipped with a magnetoresistive sensor.

[0035] FIG. 6( a ) shows a front cross-sectional view of a stator support frame of the motor of the present invention.

[0036] FIG. 6( b ) shows a three-dimensional view of the stator support frame of the motor of the present invention.

[0037] FIG. 6( c ) shows a top view of the stator support frame of the motor of the present invention.

[0038] FIG. 6( d ) shows a front view of the stator support frame of the motor of the present invention.

[0039] Figure 7 A top cross-sectional view and a partial enlarged view of the stator support frame of the present invention are shown.

[0040] FIG. 8( a ) shows a perspective view of a sealing ring of the present invention.

[0041] FIG8( b ) shows a cross-sectional view of the sealing ring of the present invention.

[0042] All the drawings are only schematic and not necessarily drawn to scale, and they only show those parts necessary for explaining the present invention, and other parts are omitted or only mentioned. That is, in addition to the parts shown in the drawings, the present invention may also include other parts.

[0043] In the figures, identical and / or functionally identical technical features are provided with identical or similar reference numerals. DETAILED DESCRIPTION

[0044] Embodiments of the present invention are described below with reference to the accompanying drawings. In the following description, many specific details are set forth so that those skilled in the art can more fully understand and implement the present invention. However, it will be apparent to those skilled in the art that the present invention may be implemented without some of these specific details. In addition, it should be understood that the present invention is not limited to the specific embodiments described. On the contrary, any combination of the features and elements described below may be considered to implement the present invention, regardless of whether they relate to different embodiments. Therefore, the following aspects, features, embodiments and advantages are intended for illustration purposes only and should not be considered as features or limitations of the claims unless explicitly stated in the claims.

[0045] In the following description, the descriptions about directions, such as "upper", "lower", "inner", "outer", "radial", "axial", etc., which may be used, are only for the convenience of description, unless otherwise specified, and are not intended to form any limitation on the technical solution of the invention. In addition, in the following description, terms such as "first", "second", etc. are used to describe the elements of the present application, and these terms are only used to distinguish the elements, and are not intended to limit the nature, sequence, order or number of these elements.

[0046] Figure 1 An exploded view of the drive system of the present invention is shown, Figure 2 shows a cross-sectional view of the drive system of the present invention, Figure 3 A perspective view of the drive system of the present invention is shown. Figures 1 to 3 It can be seen that the drive system of the present invention mainly includes two parts, namely, a motor and a ball screw 6. Specifically, the motor includes a rotor assembly 2 and a stator assembly 3, and the ball screw 6 includes a nut 61 and a screw 62 and a ball disposed therebetween. Preferably, the motor is a brushless motor.

[0047] The motor is arranged in the housing 1, and the rotor assembly adopts a surface-mounted structure. Figure 1 and Figure 2The rotor assembly 2 includes a rotor skeleton 21, a plurality of permanent magnets arranged on the inner side of the rotor skeleton 21 in a surface-mounted manner, and a metal ring 23 for further fixing the permanent magnets. The metal ring 23 is made of a non-magnetic metal material. The rotor skeleton 21 is rotatably supported in the housing 1 by a bearing 10. Preferably, the bearing 10 adopts a four-point contact ball bearing so as to simultaneously achieve axial and radial support for the rotor skeleton 21. The structure of the rotor skeleton can also be further understood in conjunction with Figures 4(a), 4(b) and 4(c). Specifically, the rotor skeleton 21 has an annular body, thereby defining an axial direction, which is also the axial direction of the motor. A plurality of axially extending protrusion structures 211 are provided on the inner wall of the annular body, and an installation space for arranging permanent magnets is formed between every two adjacent protrusion structures.

[0048] The stator assembly 3 includes a stator core, a stator winding, and an insulating frame located on both sides of the stator core. The structure of the stator assembly 3 is not limited to the structure shown in the figure, and a suitable structure known in the prior art can be adopted.

[0049] In order to drive the ball screw 6 to work, Figure 2 As can be seen in FIG. 4( c ), one end of the lead screw 62 is fixedly connected to the end of the rotor frame 21 so that it can rotate with the rotor frame 21. As a specific embodiment, referring to FIG. 4( c ), the rotor frame has a bottom, which is perpendicular to the axial direction of the motor, and at least one connecting portion 215 is provided on the bottom for connecting with the corresponding connecting portion at the end of the lead screw 62. The connecting portion 215 can be in the form of a hole, and a plurality of holes can be provided, such as 5 holes in FIG. 4( c ). Accordingly, a protrusion is provided on the lead screw 62.

[0050] Furthermore, in order to prevent the lead screw 62 from moving axially, the bottom is provided in a two-stage form. Referring to FIG. 4(a) and FIG. 4(c), it can be seen that a first bottom 213 extends radially inward from the annular body, a second bottom is axially extended from the first bottom, and a connecting portion 215 is provided on the second bottom. Accordingly, the portion connecting the first bottom and the second bottom is referred to as an axial connecting portion. A groove 214 is provided on the axial connecting portion, and a stopper 9 is provided in the groove. The stopper 9 can be in the form of a C-shaped ring. Accordingly, a corresponding portion can be provided on the lead screw 62 to cooperate with the stopper 9.

[0051] from Figure 1 and Figure 2 It can be seen that the motor of the present invention adopts an outer rotor structure. That is, the stator assembly 3 is radially accommodated inside the rotor assembly 2. Compared with the inner rotor motor known in the braking system, the outer rotor motor adopted by the present invention can provide greater torque at the same speed due to the larger radius of the rotor. The use of an outer rotor motor in the braking system is a basic inventive concept of the present invention.

[0052] Based on this basic inventive concept, the present invention also proposes the following multiple improvements.

[0053] In order to measure the operating parameters of the motor, such as the rotation speed, a sensor is provided on the motor. The known scheme is provided with a magnetoresistive sensor or an eddy current sensor. For the magnetoresistive sensor, its working principle is to measure the change in the magnetic field strength in the rotating rotor, thereby measuring the rotation speed of the rotor. The working principle of the eddy current sensor is to accurately measure the relative position of the measured object (which must be a metal conductor) and the end face of the probe through the principle of the eddy current effect. Its characteristics are good long-term working reliability, high sensitivity, strong anti-interference ability, non-contact measurement, fast response speed, and no influence from media such as oil and water. However, in the traditional inner rotor motor, if a magnetoresistive sensor is to be used, due to space limitations, the magnetic steel of the motor rotor itself cannot be used as a signal magnetic steel, and an additional signal magnetic ring must be added; if an eddy current sensor is to be used, a separate part must be installed on the rotating part, which requires a larger installation space, which will make the motor larger and more expensive. An improvement of the present invention is that, on the basis of adopting the form of an outer rotor motor, a structure is further conceived to use the form of an outer rotor to preset the operation of two sensors. Of course, those skilled in the art know that in actual use, only one sensor is required. However, the present invention provides two corresponding structures, thereby enabling the installation of two sensors to be satisfied at the same time without any adjustment.

[0054] In addition, the present invention also directly uses the rotor frame to form the components that cooperate with the eddy current sensor, achieving multiple uses without the need to additionally set up corresponding matching components, reducing the number of parts, lowering costs, and reducing volume.

[0055] Specifically, referring to FIG. 4( b ) and FIG. 4( c ), a plurality of openings 212 are provided on the first bottom 213 of the rotor skeleton 21 . Figure 2 The form in which the eddy current sensor 41 is installed is shown. The eddy current sensor itself is annular, and has a certain overlap with the first bottom 213 of the rotor skeleton 21 in the radial direction. Therefore, when the rotor skeleton 21 rotates, the eddy current sensor 41 can sense the rotation speed because it has a metal part and an opening 212. Since the present invention adopts the form of an outer rotor, the radial size of the rotor can relatively ensure the normal operation of the eddy current sensor 41, and the setting of the opening 212 will not make its strength unable to meet the requirements. The number, size and position of the opening 212 can be set as needed. In the method of Figure 4 (c), the opening 212 adopts the form of 5 evenly distributed in the circumferential direction. The eddy current sensor 41 can be installed on a fixed component such as a stator by fasteners such as screws.

[0056] Figure 5 A cross-sectional view of a drive system of the present invention with a magnetoresistive sensor installed is shown. Figure 1 , Figure 3 and Figure 5 , the magnetic resistance sensor 42 is accommodated between the housing 1 and the rotor frame 21 in the radial direction. Therefore, the magnetic steel of the motor rotor itself is used as the signal magnetic steel. When the rotor 21 rotates, the magnetic resistance sensor 42 can sense the magnetic field change of the rotor to measure the rotor speed, without the need to set up an additional signal magnetic ring.

[0057] It can be seen from the above that the present invention, based on the outer rotor, utilizes the structural form of the outer rotor to provide a storage space for the magnetoresistive sensor and a structure adapted to the eddy current sensor without providing a separate adaptation structure for each sensor.

[0058] FIG6(a) shows a front cross-sectional view of the stator support frame of the motor of the present invention, FIG6(b) shows a three-dimensional view of the stator support frame of the motor of the present invention, FIG6(c) shows a top view of the stator support frame of the motor of the present invention, and FIG6(d) shows a front view of the stator support frame of the motor of the present invention. Figure 1 , Figure 2 , it can be seen that the stator support frame is used to provide support for the stator. Specifically, the stator support frame 5 has an annular portion 51 perpendicular to the axial direction and a cylindrical portion 52 extending along the axis. On the annular portion 51, a mounting portion 54 for mounting a magnetoresistive sensor may be provided. The mounting portion 54 may be in the form of a hole. On the cylindrical portion 52, an anti-rotation portion 53 is provided to prevent the nut 61 from rotating when performing linear motion.

[0059] Since the nut 61 itself acts as a piston, when the lead screw 62 rotates with the outer rotor, the rotational motion of the lead screw 62 is converted into the linear motion of the nut 61 through the power transmission of the balls. In order to ensure the accuracy of the motion, that is, to make the nut 61 only move linearly without rotating, the rotation of the nut 61 needs to be prevented. For this purpose, see Figure 1 A groove 611 extending in the axial direction is provided on the outer wall of the nut, and the groove 611 cooperates with the anti-rotation portion 53 on the cylindrical portion 52 of the stator support frame 5 to prevent the nut 61 from rotating, so that the nut 61 can only move in the axial direction. Figure 7 The top view and partial enlarged view of the stator support frame of the present invention are shown. Figure 7 The matching structure between the anti-rotation portion 53 and the nut 61 can be more clearly seen in FIG.

[0060] As a specific implementation, the stator support frame 5 is supported by deep drawing of a plate. Specifically, after deep drawing of a plate, an annular portion 51 and a cylindrical portion 52 can be obtained. Subsequently, the cylindrical portion 52 is side-drawn to obtain the anti-rotation portion 53.

[0061] Preferably, two anti-rotation parts 53 are provided and are relatively arranged on the same diameter.

[0062] In the traditional solution, in order to prevent the nut from rotating during linear motion, two or three additional parts need to be separately arranged between the nut and the corresponding parts. This solution not only makes the structure more complicated, but also the added parts will occupy the internal space of the motor. Therefore, in addition to high cost, it is not conducive to the compact design of the motor. The present invention integrates the anti-rotation part into the stator support frame through the above arrangement, so that the stator support frame also has the anti-rotation function, realizing multiple uses of one piece without the need to set up additional parts. While meeting the functional requirements, the structure is more compact and the cost is lower.

[0063] FIG8(a) shows a stereoscopic view of the sealing ring of the present invention, and FIG8(b) shows a cross-sectional view of the sealing ring of the present invention. The driving system of the present invention can be combined with parts such as a hydraulic cylinder to form a braking system. As mentioned above, since the nut 61 itself also serves as a piston of the braking system, it is necessary to ensure the seal between it and the brake cylinder. To this end, a seal 7 is provided on the outer wall of the nut 61. Furthermore, the seal 7 is a double-lip seal having a first lip 71 and a second lip 72, with a groove between the two lips. By means of the double-lip seal, a good dynamic seal between the piston and the cylinder wall can be ensured.

[0064] In addition, in order to match the motor and ball screw of the present invention with other parts, the present invention also provides a sealing ring 11 and an electrical connector 8. The electrical connector is used to provide current and control for the motor, and the sealing ring 11 is used for sealing with other parts of the brake system.

[0065] The present invention has been clearly and completely described with reference to the above exemplary embodiments, and it should be understood by those skilled in the art that various other embodiments can be conceived by modifying the disclosed technical solutions without departing from the spirit and scope of the present invention. These embodiments should be understood to fall within the scope of the present invention determined based on the claims and any equivalent technical solutions thereof.

Claims

1. A motor, comprising: A housing having a receiving space; A stator assembly, the stator assembly is located in the accommodating space and includes a stator core and a winding; a rotor assembly, the rotor assembly being located in the accommodation space and rotatably supported by the housing; an output component, the output component being fixedly connected to the rotor assembly; It is characterized in that The stator assembly is located radially inside the rotor assembly, and the output component is located radially inside the stator assembly.

2. The motor according to claim 1, characterized in that The rotor assembly includes a rotor frame and a plurality of permanent magnets arranged on the rotor frame, the rotor frame having an annular portion extending along the axial direction of the motor and provided with the permanent magnets, and a first bottom perpendicular to the axial direction, a plurality of openings distributed in the circumferential direction are arranged on the first bottom, and the openings are used to cooperate with an eddy current sensor to detect the rotational speed of the rotor frame.

3. The motor according to claim 2, characterized in that The rotor skeleton further includes a second bottom portion spaced apart from the first bottom portion in the axial direction, and a structure connected to the output component is disposed on the second bottom portion.

4. The motor according to any one of claims 1 to 3, characterized in that: The invention also comprises a magnetoresistive sensor receiving portion for receiving the magnetoresistive sensor between the housing and the rotor assembly in a radial direction.

5. A drive system, characterized in that: include: The motor according to any one of claims 1 to 4; as well as The output component is accommodated in the hollow component, and the output component and the hollow component together form a motion conversion mechanism for converting the rotational motion of the output component into the linear motion of the hollow component.

6. The drive system according to claim 5, characterized in that: include: The motor further comprises a stator support frame, wherein the stator support frame has a cylindrical portion extending in the axial direction, and the cylindrical portion is radially located between the stator assembly and the hollow component, and an anti-rotation portion for preventing the hollow component from rotating is arranged on the cylindrical portion.

7. The drive system according to claim 6, characterized in that: include: The anti-rotation portion is a protrusion or a groove extending along the axial direction; The hollow component is provided with a groove or a protrusion matched with the protrusion or the groove.

8. The drive system according to claim 6 or 7, characterized in that: The stator support frame has an annular portion perpendicular to the axial direction, and a structure for mounting a magnetoresistive sensor is arranged on the annular portion.

9. A braking system, characterized in that: include: A drive system according to any one of claims 5 to 8; as well as A hydraulic cylinder, wherein the hollow component serves as a piston of the hydraulic cylinder.

10. The braking system according to claim 9, characterized in that: Double lip seals are provided at the ends of the hollow member.

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