CN214699142U

CN214699142U - Actuator for vehicle

Info

Publication number: CN214699142U
Application number: CN202120739754.4U
Authority: CN
Inventors: 金德铉; 金溥燮; 李东焕; 李昌洙; 赵学来
Original assignee: SL Corp
Current assignee: SL Corp
Priority date: 2020-04-16
Filing date: 2021-04-12
Publication date: 2021-11-12
Anticipated expiration: 2031-04-12
Also published as: KR102348885B1; KR20210128085A

Abstract

The utility model discloses an actuator for vehicle. The present invention relates to a vehicle actuator that is equipped with both a position sensor for sensing rotation of a motor and a position sensor for sensing rotation of an output shaft that receives driving force from the motor to drive an electronic transmission mechanism. The actuator for a vehicle includes: a motor generating a rotational force; a power transmission unit that transmits the rotational force generated by the motor; an output shaft rotated according to the transmitted rotational force; a first magnetic sensor sensing a rotation amount of a rotor formed at the motor; a second magnetic sensor that senses a rotation amount of the output shaft; and a circuit board provided with the first magnetic sensor on a first surface facing the motor side and the second magnetic sensor on a second surface facing the motor side.

Description

Actuator for vehicle

Technical Field

The present invention relates to a vehicle actuator, and more particularly, to a vehicle actuator that drives an electronic transmission mechanism by incorporating a position sensor for sensing rotation of a motor and a position sensor for sensing rotation of an output shaft driven by the motor.

Background

In general, an automatic transmission used for an automobile has a shift pattern that operates in the order of, for example, P range, R range, N range, D range, and S range, and when a vehicle is equipped with an automatic transmission in which a shift range is automatically changed according to an automobile speed or the like during driving, a shift lever is provided that enables a driver to artificially change the shift pattern of the automatic transmission according to a driving situation.

The driver of the automatic transmission vehicle can operate the shift lever to selectively manipulate the shift mode of the automatic transmission into a parking (P range), a reverse (R range), a neutral (N range), a running (D range), and the like, according to the driving conditions.

In the past, mode-switching devices of the manual/automatic integrated gearbox (tiptronic) type have been mainly used, as follows: a shift lever operated by a driver is directly connected to an automatic transmission mechanism through a mechanical mechanism, and an operating force applied to the shift lever is directly transmitted to the automatic transmission, thereby adjusting a shift pattern.

However, the conventional mode switching device for an automatic transmission that switches the shift mode by a mechanical mechanism as described above has a problem in that driving convenience is deteriorated because a force required to adjust the shift mode needs to be directly applied by the shift mechanism when the mode is switched. Further, since the transmission mechanism is provided in the center of the console on the side of the driver's seat, it is a factor of reducing the utilization rate of the space in the vehicle interior.

Therefore, an electronic transmission mechanism has been developed as follows: the electronic control device is configured to be capable of operating in a predetermined direction by a predetermined displacement amount by applying a small operating force, and then changes the shift mode of the automatic transmission by an operating medium such as an actuator or an electric motor by sensing the moving direction, the displacement amount, and the like.

Such a shift-by-wire (SBW) electronic transmission mechanism is an electronic transmission mechanism such as a push button or a rotary wheel. The electronic transmission is not connected by cables, but has been gradually expanded in specific gravity due to advantages such as excellent design and convenience in operation.

Further, the application of such an electronic transmission mechanism greatly improves the degree of freedom in designing the interior of the vehicle. Instead of a shift lever occupying a large position at a center console (center), a shift button or a shift knob that can be disposed at various positions can variously utilize a surrounding space, and has an advantage of easily sharing various vehicle type components.

On the contrary, compared with the conventional mechanical transmission mechanism, the mechanical transmission mechanism has a disadvantage in intuition, and has a possibility of erroneous operation compared with the certainty of the mechanical operation. Therefore, the electronic transmission mechanism requires position sensors for sensing the rotation of a motor that provides a basic driving force and the movement of an output shaft that receives power from the motor to move the transmission mechanism, respectively, and it is necessary to accurately display the current position of the shift position to the driver by the sensing of the position sensors and perform feedback control. In addition, in order to increase the degree of freedom in designing the interior space of the vehicle, it is also required to reduce the size of the actuator that drives the electronic transmission mechanism.

[ Prior art documents ]

[ patent document ]

U.S. patent publication No. 10125699 (granted 2018.11.13)

SUMMERY OF THE UTILITY MODEL

The present invention is to provide an actuator for a vehicle, comprising: a position sensor for sensing rotation of a motor and a position sensor for sensing rotation of an output shaft receiving a driving force from the motor are simultaneously provided, thereby more accurately driving the electronic transmission mechanism.

Another object of the present invention is to improve the degree of freedom in design of the indoor space of the vehicle by downsizing the actuator.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a motor position sensor and a motor position sensor that can sense the rotation of an output shaft without interfering with each other when sensing the position.

The technical problems of the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by those skilled in the art through the following descriptions.

In order to solve the above-mentioned technical problem, an actuator for a vehicle according to an embodiment of the present invention includes: a motor generating a rotational force; a power transmission unit that transmits the rotational force generated by the motor; an output shaft rotated according to the transmitted rotational force; a first magnetic sensor that senses a rotation amount of a rotor formed at the motor; a second magnetic sensor that senses a rotation amount of the output shaft; and a circuit board provided with the first magnetic sensor on a first surface facing the motor side and the second magnetic sensor on a second surface facing the output shaft side.

The vehicle actuator further includes a shield member that is disposed on the first surface side of the circuit board, and shields a magnetic field generated from the motor to prevent the magnetic field from flowing into the second magnetic sensor.

The first magnetic sensor and the second magnetic sensor are provided at positions on the circuit board that do not overlap with each other with reference to a thickness direction of the circuit board.

The shielding member includes: and an opening (opening) that penetrates between the first magnetic sensor and the motor and allows the magnetic field generated by the motor to be sensed by the first magnetic sensor.

The shielding member is made of a conductive metal material.

On the outer peripheral surface of the rotor, a plurality of rotor magnets having polarities different from each other are alternately arranged in a circumferential direction.

The first magnetic sensor includes: a plurality of magnetic sensors arranged in a circumferential direction along a rotation direction of the rotor.

The actuator for a vehicle further includes: and a rotating plate which rotates coaxially with the output shaft, wherein an output sensing magnet is mounted on a lower surface of the rotating plate, and a change in a magnetic field of the output sensing magnet generated by rotation of the output shaft is sensed by the second magnetic sensor.

The output sensing magnet has a shape extending by a predetermined angle in a rotation direction of the rotation plate.

The output sensing magnet has a first polarity and a second polarity along a rotation direction of the rotation plate.

The motor, the circuit board, and the output shaft are arranged on a same axis.

The actuator for a vehicle further includes: and a circuit substrate housing which houses the circuit substrate and includes a housing cover and a chassis.

The shielding member is mounted on a lower surface of the circuit board case.

The circuit board, the circuit board case, and the shielding member are each provided with a hollow portion, and a motor shaft extending from the motor penetrates all of the circuit board, the circuit board case, and the shielding member and is connected to the power transmission portion.

The power transmission part is a cycloid speed reducer including an eccentric shaft directly connected to the motor to convert a circular rotational force into a wave-shaped power, a cycloid disc transmitting the speed-reducing power to the output shaft according to the wave-shaped power of the eccentric shaft, and an annular case having an inner circumferential surface tooth form in tooth form contact with an outer circumferential surface of the cycloid disc.

The cycloidal wire coil is characterized by also comprising a rotating plate which rotates together with the output shaft on the same axis, wherein the rotating plate is fixedly combined with the cycloidal wire coil.

An output sensing magnet is installed between the lower surface of the rotating plate and a cycloid disc fixedly combined with the rotating plate, a through hole (alert) corresponding to the output sensing magnet is formed on the cycloid disc, and the second magnetic sensor provided on the circuit substrate senses a magnetic field generated by the output sensing magnet without hindrance.

The actuator for a vehicle further includes: and a module case including an upper case cover and a case, and housing the motor, the power transmission unit, the output shaft, and the circuit board inside.

An opening portion is formed at the upper housing cover to enable the output shaft to be connected to the outside of the module housing.

With the actuator for a vehicle according to the present invention, the shaft of the motor and the output shaft of the actuator are arranged coaxially, and the first position sensor that senses the rotation of the motor and the second position sensor that senses the rotation of the output shaft are arranged on a single circuit board, so that the actuator for a vehicle can be miniaturized and the number of packages constituting the actuator for a vehicle can be reduced.

And, the sensing area of the first position sensor and the sensing area of the second position sensor are shielded from each other, so that interference with each other is minimized when sensing the position of the position sensor, and thus the sensing performance of the position sensor can be improved.

Drawings

Fig. 1a is a perspective view illustrating an actuator 100 for a vehicle according to an embodiment of the present invention.

Fig. 1b is a perspective view of the assembly housing 110 separated from the vehicle actuator 100 of fig. 1 a.

Fig. 2 is a perspective view illustrating a process of assembling the case cover 111 and the set cover 113 according to an embodiment of the present invention.

Fig. 3a is an exploded perspective view of the vehicle actuator 100 of fig. 1a as viewed from above, and fig. 3b is an exploded perspective view of the vehicle actuator 100 of fig. 1a as viewed from below.

Fig. 4a and 4b are exploded perspective views respectively viewed from above and below to explain the configuration of the sensor unit 140 in more detail.

Fig. 5 is an exploded perspective view illustrating the configuration of the motor 120 in more detail.

Fig. 6a and 6b are exploded perspective views respectively viewed from above and below to show the configuration of the power transmission unit 130 of fig. 3a in more detail.

Fig. 7 is an exploded perspective view illustrating an assembly of the motor shaft 125 and the eccentric shaft 131 according to an embodiment of the present invention.

Description of reference numerals:

100: vehicle actuator 110: component housing

111: the housing cover 113: casing (CN)

114: the socket 115: wiring

120: motor 121: stator

122: core 123: rotor

125: the motor shaft 127: rotor magnet

130: power transmission unit 131: eccentric shaft

133: cycloid disc 135: ring-shaped box

136. 138, 144: bearing 139: through hole

140: the sensor assembly 141: upper shell

142. 156, 157: hollow portion 143: lower casing

150: circuit board 152: first magnetic sensor

154: second magnetic sensor 155: shielding component

159: opening 160: output shaft

163: output sensing magnet 165: rotary plate

169: groove

Detailed Description

The advantages, features and methods of achieving the objects of the present invention will be apparent from the following detailed description of embodiments taken in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, and can be realized in various forms different from each other, and the provision of the embodiment is only intended to make the disclosure of the present invention complete and to inform a person having basic knowledge in the technical field to which the present invention belongs completely, and the present invention is defined only by the contents described in the claims. Like reference numerals refer to like elements throughout the specification.

Unless otherwise defined, all terms (including technical and scientific terms) used in this specification shall have the same meaning as commonly understood by one having the ordinary knowledge in the art to which this invention belongs. Also, terms defined in commonly used dictionaries are not intended to be interpreted in an idealized or overly formal sense unless expressly so defined herein.

The terminology used in the description is for the purpose of describing the embodiments and is not intended to be limiting of the invention. In this specification, the singular forms also include the plural forms in the sentence, unless otherwise specified. The terms "comprising" and/or "including" used in the specification mean that the presence or addition of one or more other constituent elements than the mentioned constituent elements is not excluded.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

Fig. 1a is a perspective view illustrating a vehicle actuator 100 according to an embodiment of the present invention, and fig. 1b is a perspective view of a module case 110 separated from the vehicle actuator 100 of fig. 1 a.

Referring to fig. 1a, the constituent elements of the vehicle actuator 100 are disposed within a module case 110. The output shaft 160 may be exposed to the outside through an upper side of the assembly housing 110, and a receptacle 114 is formed at one side of the assembly housing 110 so that an electrical connector may be inserted.

As known to those skilled in the art, the upper and lower concepts are relative concepts that can be varied depending on the direction in which the actuator 100 for a vehicle is arranged. However, in the following description of the present invention, as shown in fig. 1a, the direction in which the output shaft 160 extends from the vehicle actuator 100 and protrudes is defined as the upper side.

As shown in fig. 1b, the module case 110 may include a case 113 accommodating other components and a case cover 111 covering the case 113. However, this is merely an example, and it is obvious that the configuration as the component housing 110 may be designed differently.

The housing cover 111 may be formed with an opening portion 117 so that the output shaft 160 is exposed to the outside of the actuator 100 for a vehicle through the opening portion 117. The output shaft 160 exposed to the outside as described above may be directly or indirectly connected to various electronic transmission mechanisms (not shown) such as a wheel type, a button type, a lever type, etc., and may be moved under the control of a microprocessor.

A wiring 115 for supplying power and control signals to the vehicle actuator 100 and transmitting an output signal generated by the vehicle actuator 100 may be disposed at the receptacle 114 of the housing 113.

Fig. 2 is a perspective view illustrating a process of assembling the case cover 111 and the cabinet 113 according to an embodiment of the present invention. The same number of coupling holes are provided in the case cover 111 and the cabinet 113 at corresponding positions, respectively. Nuts 116 may be provided in the coupling holes of the housing 113, and the nuts 116 may be fastened to the bolts 112 corresponding to the nuts 116 through the through holes of the housing cover 111. The assembly between the case cover 111 and the case 113 can be completed through such a process, and all the components except the output shaft 160 are housed in the pack case 110.

The actuator 100 for a vehicle may include: a motor 120 generating a rotational force; a power transmission unit 130 for transmitting the rotational force generated by the motor 120; an output shaft 160 rotated by the transmitted rotational force; the sensor module 140 senses the rotational amount of the rotor 123 included in the motor and the rotational amount of the output shaft 160, and the

components

120, 130, 140, and 160 are disposed in the module case 110 including the case cover 111 and the case 113.

The motor 120 basically includes: a stator 121 fixedly disposed and wound with a coil through which current flows; a rotor 123 equipped with a permanent magnet and rotating with respect to the stator 121; and a motor shaft 125 extending from the rotor 123 and rotating together with the rotor 123.

The motor shaft 125 drives the power transmission unit 130, and the driven power transmission unit 130 transmits power to the output shaft 160, and finally operates an electronic transmission mechanism (not shown) outside the vehicle actuator 100 through the output shaft 160.

At this time, a power supply for flowing a current to the coil wound around the stator 121 and a power supply for operating the sensor module 140 may be supplied through a portion of the wiring 115 provided in the socket 114 formed at one side of the housing 113. Further, information on the amount of rotation of the rotor 123 and the amount of rotation of the output shaft 160 sensed by the sensor unit 140 can be transmitted to a microprocessor outside the vehicle actuator 100 through another portion of the wiring 115.

Fig. 4a and 4b are exploded perspective views viewed from above and below, respectively, to explain the structure of the sensor unit 140 in more detail.

The sensor assembly 140 includes: a circuit board 150 to which a plurality of magnetic sensors are attached; and a shielding member 155 disposed on a lower surface side of the circuit substrate 150. The sensor module 140 may further include

circuit board cases

141 and 143 each including an upper case 141 and a lower case 143 for housing the circuit board 150.

Here, the circuit board 150 is provided with a first magnetic sensor 152 that senses a rotational amount (rotation angle to rotation speed) of the rotor 123 included in the motor 120, and a second magnetic sensor 154 that senses a rotational amount (rotation angle to rotation speed) of the output shaft 160. In the circuit board 150, the first magnetic sensor 152 may be disposed on a lower surface 151 facing the motor 120, and the second magnetic sensor 154 may be disposed on an upper surface 153 facing the output shaft 160. However, the circuit board 150 is not necessarily limited to this, and is generally formed of a material through which a magnetic field can be transmitted to a certain extent, and therefore, the first magnetic sensor 152 and the second magnetic sensor 154 may be all provided on the upper surface 153, or the first magnetic sensor 152 and the second magnetic sensor 154 may be all provided on the lower surface 151. However, if the first magnetic sensor 152 is provided on the lower surface 151 of the circuit board 150 and the second magnetic sensor 154 is provided on the upper surface 153 of the circuit board 150, there is no hindrance when each sensor senses the magnetic field for which it is responsible, and therefore there is an advantage that a magnetic sensor having relatively low sensitivity or less expensive can be used.

Also, the shielding member 155 is disposed on the lower surface 151 side of the circuit substrate 150, thereby having a function of shielding the magnetic field generated from the motor 120 from flowing into the second magnetic sensor 154. For example, the shielding member 155 may be mounted on the lower surface of the chassis 113 of the circuit substrate case. In order to have such a shielding function, the shielding member 155 may be made of a conductive material, and preferably, a metal material.

At this time, the shield member 155 may have an opening (opening)159 penetrating between the first magnetic sensor 152 and the motor 120. The opening 159 allows the first magnetic sensor 152 to sense the magnetic field generated in the motor 120 without hindrance.

As described above, the first and second

magnetic sensors

152 and 154 formed on both

surfaces

151 and 153 of the same circuit board 150 can smoothly measure the magnetic field without interference of other magnetic fields when sensing the rotation amount of the rotor 123 and the rotation amount of the output shaft 160, respectively. Therefore, the first magnetic sensor 152 and the second magnetic sensor 154 need not be provided at positions on the circuit board 150 overlapping in the thickness direction (longitudinal direction) of the circuit board 150, and are preferably spaced as far as possible.

Therefore, referring to fig. 4a and 4b, it can be seen that the position where the first magnetic sensor 152 is disposed and the position where the second magnetic sensor 154 is disposed are located at the farthest positions when viewed in the circumferential direction of the circuit board 150. Also, since the opening portion 159 of the shielding member 155 is formed only in the vicinity of the position where the first magnetic sensor 152 is disposed, even if the magnetic field acting through this opening portion 159 is smoothly sensed by the first magnetic sensor 152, the influence on the second magnetic sensor 154 located at a position spaced apart from the first magnetic sensor 152 can be minimized.

In addition, according to an embodiment of the present invention, as shown in fig. 3a and 3b, in order to reduce the overall size of the vehicle actuator 100, the components housed in the module case 110 are arranged coaxially. Therefore, the motor shaft 125 needs to pass through the sensor unit 140 and be connected to the power transmission unit 130 and the output shaft 160, and therefore, the sensor unit 140 is formed with a hollow portion 142 through which the motor shaft 125 passes. In order to allow the motor shaft 125 to penetrate, at least part of the

hollow portions

156 and 157 may be formed in the circuit board 150 and the shield member 155 housed in the sensor unit 140. Accordingly, the stator 121, the rotor 123, and the motor shaft 125 included in the motor 120 may be coaxially disposed with the circuit substrate 150 and the output shaft 160.

Fig. 5 is an exploded perspective view illustrating the configuration of the motor 120 in more detail. Referring to fig. 5, the motor 120 includes: a stator 121 fixed in the pack case 110; a rotor 123 rotatable with respect to the stator 121; and a motor shaft 125 that rotates integrally with the rotor 123.

The stator 121 includes: a plurality of cores 122 substantially constituting a ring shape and arranged in a circumferential direction; and a coil (not shown) wound around the plurality of cores 122 and through which current flows. The rotor 123 includes a permanent magnet, has a substantially cylindrical shape, and rotates with respect to the stator 121 with reference to the motor shaft 125 without contacting the stator 121. As an example, on the outer circumferential surface of the rotor 123, a plurality of rotor magnets 127 having polarities (N, S) different from each other may be alternately arranged in the circumferential direction. Accordingly, the first magnetic sensor 152 may sense a change in a magnetic field generated according to the rotation of the rotor 123, thereby sensing the amount of rotation of the rotor 123.

Although the first magnetic sensor 152 may be configured by only one magnetic sensor, in order to more accurately sense the amount of rotation of the rotor 123 rotating at a high speed, it may be configured by a plurality of magnetic sensors, and preferably, it may be configured by three magnetic sensors. As shown in fig. 4b, the first magnetic sensor 152 may be configured with a plurality of magnetic sensors arranged at intervals in the circumferential direction in the rotational direction of the rotor 123.

When the plurality of rotor magnets 127 alternately arranged in the rotor 123 in the circumferential direction are rotated, although the magnetic signal input to the first magnetic sensor 152 is close to a pure sine wave, a part of the deformation may be generated by an external factor. Such distortion of the magnetic signal causes a significant error in detecting the position of the rotor, making accurate measurement difficult. In view of this, the first magnetic sensor 152 may be configured with a plurality of magnetic sensors arranged at intervals in the circumferential direction, so as to remove or reduce such errors based on sensing values different from each other.

Fig. 6a and 6b are exploded perspective views, respectively viewed from above and below, to illustrate the configuration of the power transmission unit 130 of fig. 3a in more detail. The power transmission portion 130 transmits the rotational force generated at the motor 120 to the output shaft 160, and generally has a deceleration function. Therefore, as the rotational speed of the output shaft 160 is decelerated to be less than the rotational speed of the motor shaft 125, the torque of the output shaft 160 may be increased by the degree of the deceleration.

As an example, as shown in fig. 6a, the power transmission unit 130 may be configured by a cycloidal reducer (cycloidal reducer). However, this type of cycloid speed reducer is only an embodiment of the present invention, and as long as the motor 120, the power transmission unit 130, and the output shaft 160 can be coaxially arranged, other components such as a harmonic drive (harmonic drive), a planetary gear reducer (planetary gear reducer), and a general gear reducer may be used instead of the power transmission unit 130. However, a cycloid speed reducer will be exemplarily described below as the power transmission portion 130.

The cycloid speed reducer is a mechanism that transmits power and operates by utilizing continuously contacting cycloid tooth profiles. Here, an eccentric shaft (eccentric shaft)131, a cycloid disc (cycloidal disc)133, and a ring box (cyclo box)135 are used as three main basic components. The cycloid speed reducer is formed by a continuous curve having a uniform tooth profile, that is, a cycloid, and therefore, all points are in rotational contact, thereby exhibiting high efficiency, and also, since the cycloid speed reducer has a large number of meshing teeth, a strong structure, and a large reduction ratio due to its small size and light weight, and is driven by a multi-mesh and continuous rolling contact system, there is an advantage of low noise and interference.

Referring to fig. 6a and 6b, the eccentric shaft 131 may be assembled to the motor shaft 125 alone or manufactured as one body with the motor shaft 125. Such an eccentric shaft 131 converts the circular rotational force supplied from the motor 120 into a wave-shaped power. For this purpose, the portion (bearing, not shown) where the eccentric shaft 131 is coupled to the cycloid disc 133 is slightly eccentric with respect to the axis of the motor shaft 125, and such eccentric structure provides the power of the wave form.

The cycloid disc 133 is assembled with the eccentric shaft 131 with bearings interposed therebetween, thereby transmitting the deceleration power to the output shaft 160 according to the power of the wave form of the eccentric shaft. The annular case 135 has an inner peripheral surface tooth profile in tooth contact with the outer peripheral surface of the cycloid disc 133. The ring case 135 is a rigid ring-shaped member having a module tooth shape similar to the cycloid disk 133 on the inner circumferential surface and having a number slightly larger than the number of teeth of the cycloid disk 133. Therefore, the reduction power transmitted to the output shaft 160 is determined according to the reduction ratio due to the difference in the size and the number of teeth of such toothed modules.

At this time, the output shaft 160 may be supported for rotation by a bearing 161 provided to the assembly housing 110 (particularly, the housing cover 111). The output shaft 160 may include a rotation plate 165 coaxially rotating together, and the rotation plate 165 may be fixedly coupled to the cycloid disc 133. For example, as shown in fig. 6b, three protrusions 166 are formed on the lower surface of the rotating plate 165, and the three protrusions 166 are coupled to the three through holes 149 formed on the cycloid disc 133.

Here, in order for the sensor module 140 to sense the rotation amount of the output shaft 160, an output sensing magnet 163 rotating together with the output shaft 160 is fixedly provided at one side of the output shaft 160. Specifically, as shown in fig. 6b, the output sensing magnet 163 may be disposed in a groove (groove)169 formed on a lower surface of the rotation plate 165 that rotates integrally with the output shaft 160.

Further, the output sensing magnet 163 may be disposed between the lower surface of the rotation plate 165 and the cycloid disc 133 fixedly coupled to the rotation plate 165. In this case, the cycloid disc 133 has a through-hole (aperture)139 corresponding to the output sensing magnet 163, so that the second magnetic sensor 154 provided at the circuit substrate 150 of the sensor module 140 can sense the magnetic field generated by the output sensing magnet 163 without hindrance.

As shown in fig. 6a and 6b, the output sensing magnet 163 may be configured to extend at a predetermined angle in the rotation direction of the rotation plate 165. At this time, the output sensing magnet 163 may have a first polarity (N) and a second polarity (S) in the rotation direction of the rotation plate 165.

Fig. 7 is a perspective view illustrating an assembly of the motor shaft 125 and the eccentric shaft 131 according to an embodiment of the present invention. The assembly may be formed by assembling the motor shaft 125 and the eccentric shaft 131 with each other, or may be integrally formed to have a single body.

The motor shaft 125 is coaxially formed at both ends thereof and supported by the inner diameters of the

bearings

138 and 144, respectively. Of the

bearings

138 and 144, the lower bearing 144 may have an outer diameter fixed to one side of the module case 110 (particularly, the housing 113), and the upper bearing 138 may have an outer diameter fixed to the rotating plate 165 to the output shaft 160. The outer diameter of the eccentric shaft 131 formed eccentrically with respect to the coaxial shaft may be supported by the inner diameter of the bearing 136, and the outer diameter of the bearing 136 is fixed in the hollow portion of the cycloid disc 133.

Although the embodiments of the present invention have been described with reference to the above drawings, those skilled in the art to which the present invention pertains will be able to understand that the present invention can be implemented in other specific forms without changing the technical ideas or necessary features. It is therefore to be understood that the above-described embodiments are illustrative in all respects, and not restrictive.

Claims

1. An actuator for a vehicle, characterized by comprising:

a motor generating a rotational force;

a power transmission unit that transmits the rotational force generated by the motor;

an output shaft rotated according to the transmitted rotational force;

a first magnetic sensor that senses a rotation amount of a rotor provided to the motor;

a second magnetic sensor that senses a rotation amount of the output shaft; and

and a circuit board provided with the first magnetic sensor and the second magnetic sensor.

2. The actuator for vehicle according to claim 1,

the circuit board is provided with the first magnetic sensor on a first surface facing the motor side, and is provided with the second magnetic sensor on a second surface facing the output shaft side.

3. The actuator for vehicle according to claim 2, further comprising:

and a shielding member disposed on the first surface side of the circuit board, the shielding member shielding a magnetic field generated from the motor to prevent the magnetic field from flowing into the second magnetic sensor.

4. The actuator for vehicle according to claim 1,

5. The actuator for vehicle according to claim 4,

the first magnetic sensor and the second magnetic sensor are provided at positions farthest from each other on a circumference formed by the circuit substrate.

6. The actuator for vehicle according to claim 3,

the shielding member includes:

and an opening portion that penetrates between the first magnetic sensor and the motor and enables the first magnetic sensor to sense a magnetic field generated by the motor.

7. The actuator for vehicle according to claim 3,

the shielding member is made of a conductive metal material.

8. The actuator for vehicle according to claim 1,

9. The actuator for vehicle according to claim 1,

the first magnetic sensor includes:

a plurality of magnetic sensors arranged in a circumferential direction along a rotation direction of the rotor.

10. The actuator for a vehicle according to claim 1, further comprising:

a rotating plate which rotates coaxially with the output shaft,

wherein an output sensing magnet is mounted on a lower surface of the rotation plate, and a change in a magnetic field of the output sensing magnet generated according to rotation of the output shaft is sensed by the second magnetic sensor.

11. The actuator for vehicle according to claim 10,

12. The actuator for vehicle according to claim 11,

13. The actuator for vehicle according to claim 3,

the motor, the circuit board, and the output shaft are arranged coaxially.

14. The actuator for vehicle according to claim 13, further comprising:

and a circuit substrate housing which houses the circuit substrate and includes a housing cover and a chassis.

15. The actuator for vehicle according to claim 14,

the shielding member is mounted on a lower surface of the circuit board case.

16. The actuator for vehicle according to claim 15,

17. The actuator for vehicle according to claim 1,

the power transmission part is a cycloid reducer comprising an eccentric shaft, a cycloid disc and an annular box,

the eccentric shaft is directly connected with the motor to convert the circular rotating force into the wave-shaped power,

the cycloid disc transmits the deceleration power to the output shaft according to the power of the wave form of the eccentric shaft,

the annular box is provided with an inner peripheral surface tooth form which is in tooth form contact with the outer peripheral surface of the cycloid disc.

18. The actuator for vehicle according to claim 17, further comprising:

a rotating plate which rotates coaxially with the output shaft,

wherein, the rotating plate is fixedly combined with the cycloid disc.

19. The actuator for vehicle according to claim 18,

an output sensing magnet is arranged between the lower surface of the rotating plate and the cycloid disc fixedly combined with the rotating plate,

the cycloid disc is formed with a through hole corresponding to the output sensing magnet, and the second magnetic sensor provided on the circuit board senses the magnetic field generated by the output sensing magnet without hindrance.

20. The actuator for a vehicle according to claim 1, further comprising:

and a module case including an upper case cover and a case, and housing the motor, the power transmission unit, the output shaft, and the circuit board inside.

21. The actuator for vehicle according to claim 20,