Torque actuator

Abstract

The present invention provides a torque actuator, comprising a sealing component, a rotor component, a stator component, an output shaft and a sensor component; a container space is formed inside the sealing component, and the rotor component and the stator component are installed in the container space; the rotor component comprises a magnetic sheet, the stator component comprises a stator, and the stator comprises a stator core and a coil component; the magnetic sheet is located at one end of the stator core in the axial direction; the rotor component is tightly connected to the output shaft, and the output shaft extends in the axial direction to reach outside the container space; the sensor component comprises an eccentric wheel and an angle sensor, and the rotor component and / or the output shaft are tightly connected to the eccentric wheel. The angle position sensor used in the present invention is installed above the rotor substrate, and detects the position and outputs the angle position signal in real time through the eccentric wheel on the mounting shaft, and outputs it to an external controller. It is not affected by the magnetic circuit during operation, and the operation is more stable and the corresponding accuracy is higher.

Description

Technical Field

[0001] The present invention relates to the technical field of engine fuel regulation, and in particular to a torque actuator. Background Art

[0002] As a speed control actuator, the torque actuator requires fast dynamic response, high steady-state accuracy, and strong environmental adaptability. Under current domestic conditions, it is difficult to form the serialization and mass production capacity of the actuator, which has greatly hindered the promotion, application and development of this technology. The difficulties in the development of the torque actuator as an electronic speed regulator are mainly: first, the friction resistance is relatively large, so the static characteristics are not good. Whether the friction resistance can be effectively overcome and the static characteristics can be improved is the key; second, the control accuracy during its working process. Its precision control is reflected in the close cooperation between the various components inside the actuator. The accurate monitoring of its output characteristics is closely related to the accurate measurement of the internal sensors. Considering its reliability and the requirement for the longest possible life, the layout and design of the internal structure are particularly important.

[0003] Patent document CN104377843B provides a sealed claw-pole axial magnetic circuit permanent magnet brushless DC motor, the motor stator is a base around which claw poles are fixed vertically and evenly, the center line of the claw pole is parallel to the axis of the rotating shaft, the claw pole is mounted with coil windings, the motor stator base, the coil windings on the base claw poles are sealed with plastic material to form a barrel-shaped plastic seal, and a cover is sealed on the barrel-shaped plastic seal, the motor rotor shaft passes through the stator base, the iron core is fixed vertically, the permanent magnet magnet is evenly fixed on the iron core, and a sensor magnet is fixed at the center of the other surface of the iron core, and the sensor magnet corresponds to the Hall sensor fixed on the inner wall of the cover. According to the patent document, the generator adopts an axial magnetic circuit, has a large torque and high efficiency; at the same time, it has a small size and space, and has strong system integration. However, in this patent document, the Hall sensor is fixed on the inner wall of the cover and corresponds to the sensor magnet fixed on the center position of the other surface of the iron core. The sensor magnet is axially magnetized. During operation, the magnetic circuits of the stator and rotor will pass through the sensor, affecting the operation of the sensor. In addition, this patent document uses a single bearing support. When applied to larger actuators, friction loss is prone to occur, which reduces the service life and reliability. At the same time, there are certain defects in the axial positioning. Summary of the invention

[0004] In view of the defects in the prior art, an object of the present invention is to provide a torque actuator.

[0005] The torque actuator provided by the present invention comprises a sealing assembly, a rotor assembly, a stator assembly, an output shaft and a sensor assembly;

[0006] A container space is formed inside the sealing assembly, and the rotor assembly and the stator assembly are installed in the container space;

[0007] The rotor assembly includes a magnetic sheet, the stator assembly includes a stator, and the stator includes a stator core and a coil assembly; the magnetic sheet is located at one end of the stator core in the axial direction;

[0008] The rotor assembly is tightly connected to the output shaft, and the output shaft extends in the axial direction to the outside of the container space;

[0009] The sensor assembly comprises an eccentric wheel and a rotation angle sensor, and the rotor assembly and / or the output shaft are firmly connected to the eccentric wheel.

[0010] Preferably, the sealing assembly comprises an outer cover shell and an upper cover plate; the outer cover shell and the upper cover plate are fastened together;

[0011] The two ends of the output shaft along the axial direction extend through the outer cover shell and the upper cover plate to reach the outside of the container space.

[0012] Preferably, the device further comprises a bearing, wherein the plurality of bearings comprises a first bearing and a second bearing;

[0013] The output shaft is rotatably connected to the upper cover plate and the outer cover shell through a first bearing and a second bearing respectively.

[0014] Preferably, the rotor assembly further comprises a rotor substrate, and 2n magnetic sheets are evenly distributed on the rotor substrate along the circumferential direction, wherein n is a positive integer;

[0015] The extension direction between the two poles of the magnetic sheet NS is parallel to the axial direction of the stator core; along the circumferential direction, the magnetic poles of two adjacent magnetic sheets are arranged oppositely.

[0016] Preferably, the stator assembly further comprises a stator substrate; a plurality of stators are evenly distributed on the stator substrate along the circumferential direction;

[0017] The number of stators is equal to the number of magnetic sheets.

[0018] Preferably, the stator assembly further comprises potting, wherein the potting fixes the stator and the stator substrate in the container space.

[0019] Preferably, the magnetic sheet, the rotor substrate and the rotation angle sensor are arranged in sequence along the axial direction of the output shaft.

[0020] Preferably, it further comprises a controller, wherein the controller comprises the following modules:

[0021] Signal acquisition module: acquires adjustment command signals and / or signals reflecting the turning angle position from the turning angle sensor;

[0022] Power-on control module: controls the power-on of the coil assembly according to the adjustment command signal and / or the signal reflecting the angle position from the angle sensor.

[0023] Preferably, the first bearing and the second bearing are both needle bearings.

[0024] Preferably, the outer cover shell is provided with a bottom boss, and the rotor substrate is installed between the outer wall surface of the bottom boss and the inner wall surface of the outer cover shell;

[0025] An opening is arranged at the bottom of the outer cover shell, and a fastener passes through the opening to fasten and connect the rotor base plate and the stator core.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1. The angle position sensor used in the present invention is installed above the rotor substrate. The eccentric wheel on the mounting shaft is used to detect the position and output the angular position signal in real time, and output it to the external controller. It is not affected by the magnetic circuit during operation, and the operation is more stable and the corresponding accuracy is higher.

[0028] 2. The present invention adopts two upper and lower bearing supports, which can effectively reduce friction loss, improve service life and reliability, and is suitable for the manufacture of actuators with larger sizes; at the same time, the use of two upper and lower bearings has a good axial positioning effect during the assembly process.

[0029] 3. In the present invention, after the rotor reaches the set position, only a very small maintaining current is required to fix the output position, and the power consumption is greatly reduced. Due to the multi-pole form, the efficiency is improved, the volume is small, and the mass is low, which meets the application requirements of the engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0031] Figure 1 It is a front cross-sectional view of the present invention;

[0032] Figure 2 is a schematic diagram of the three-dimensional structure of the stator assembly;

[0033] Figure 3 is a cross-sectional schematic diagram of a stator assembly;

[0034] Figure 4 is a schematic diagram of the three-dimensional structure of the rotor assembly;

[0035] Figure 5 is a schematic cross-sectional view of a rotor assembly;

[0036] Figure 6 It is a schematic diagram of torque output of the present invention.

[0037] The figure shows:

[0038] DETAILED DESCRIPTION

[0039] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several variations and improvements may be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0040] In the description of the present invention, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0041] like Figure 1 As shown, the torque sensor provided by the present invention comprises a sealing assembly, a rotor assembly, a stator assembly, an output shaft 5 and a sensor assembly. The sealing assembly comprises an outer cover shell 1 and an upper cover plate 4, the outer cover shell 1 and the upper cover plate 4 are fastened together, a container space is formed inside the sealing assembly, and the rotor assembly, the stator assembly and the sensor are all located in the container space. Figure 4 , Figure 5 As shown, the rotor assembly includes a rotor substrate 7 and a magnetic sheet 8, the output shaft 5 is firmly connected to the rotor substrate 7, and the magnetic sheet 8 is a permanent magnet and is fixed on the lower end surface of the rotor substrate 7. Figure 2 , Figure 3 As shown, the stator assembly includes a stator core 9, a coil assembly 10, a stator substrate 11 and a potting 13. The stator core 9 and the coil assembly 10 form a stator. The stator substrate 11 is mounted on the inner bottom surface of the outer cover shell 1. Multiple stators are mounted on the stator substrate 11 along the circumferential direction. The potting 13 seals and fixes the stator and the stator substrate 11, and also fixes the entire stator assembly in the container space. In addition, a bottom boss is provided on the outer cover shell, and the rotor substrate 7 is installed between the outer wall surface of the bottom boss and the inner wall surface of the outer cover shell 1, which plays a good radial positioning role for the stator substrate. An opening is provided at the bottom of the outer cover shell, and a fastener such as a screw is used to pass through the opening to fasten the rotor substrate 7 and the stator core 9, which plays a good axial positioning role. The sensor includes an angle sensor and an eccentric wheel 3. The rotor assembly and / or the output shaft 5 are fastened to the eccentric wheel 3. The angle sensor is correspondingly arranged with the eccentric wheel 3 to detect the angular position of the output shaft 5. In addition, the output shaft 5 is connected to the sealing assembly through a bearing to ensure smooth rotation.

[0042] When designing the present invention, it was considered that when the structure of the Hall sensor and the magnetic steel is adopted in the prior art, the Hall sensor will be affected by the magnetic field of the magnetic steel and the magnetic sheet 8 on the rotor assembly at the same time, which will cause a large error in the detection result. Therefore, the structure of the eccentric wheel 3 and the angle sensor 2 such as the eddy current sensor is adopted. The angle sensor 2 is installed above the rotor substrate 7. The position is detected and the angle position signal is output in real time through the eccentric wheel 3 installed on the shaft, and the signal is output to the external controller. The eccentric wheel 3 is not affected by the magnetic circuit during operation, and the operation is more stable and the corresponding accuracy is higher. Of course, the eccentric wheel 3 can also be a structure such as a cam whose radial length changes with the angular position. Furthermore, the eccentric wheel 3 adopted can be nested and connected with the output shaft 5, and the angle sensor 2 is provided with a side along the radial direction of the output shaft 5 rather than the axial direction, so that the output shaft 5 can pass through the upper cover plate 4 upward in the axial direction on the basis of the existing downward penetration structure to form a bidirectional output. Figure 1 The assembly method reflected in the figure is that the output shaft 5 is rotationally connected to the upper cover plate 4 and the outer cover shell 1 through the first bearing 6 and the second bearing 12 respectively, and the two ends of the output shaft 5 along the axial direction respectively penetrate the upper cover plate 4 and the lower end surface of the outer cover shell 1 to reach the outside of the storage space. Considering the service life and reliability of the torque actuator in actual application, especially for torque actuators with larger sizes, the use of two bearings can further reduce friction losses. At the same time, during the assembly process, the structure of the upper and lower bearings also unexpectedly achieves a good axial positioning effect, reducing the axial movement of the output shaft 5 during operation. Of course, in the preferred example, more bearings can be provided to further enhance the above-mentioned beneficial effects, but the size requirements and assembly requirements for the torque actuator will increase with the increase in the number of bearings. In the embodiment, the first bearing 6 and the second bearing 12 are both needle bearings. In the preferred example, the first bearing 6 and the second bearing 12 may also be deep groove ball bearings, which are suitable for higher rotation speeds. However, the radial load-bearing capacity of deep groove ball bearings is poor, and the radial space size is large, which is not conducive to the miniaturization of the overall structure. Preferably, only one needle bearing structure may be used to save manufacturing costs, but the friction of the output shaft 5 will be relatively large, which will seriously affect the output characteristics of the present invention.

[0043] During assembly of the present invention, a certain air gap is ensured between the magnetic sheet 8 and the stator core 9, and the air gap is related to the output torque of the actuator. In the design of the electric actuator, different stator core 9 pole pairs n can be designed according to different output angle range requirements. At this time, the number of magnetic sheets 8 is 2n, where n is a positive integer. The stator core 9 and the magnetic sheet 8 need to be axially symmetrically distributed along the central axis in the electric actuator structure. In addition, in the circumferential direction, when adjacent stators are energized, the current directions in the coil assembly 10 are opposite, all magnetic sheets 8 are axially magnetized, and in the circumferential direction, the magnetic field polarities of adjacent magnetic sheets 8 are opposite. When the motor is in the initial position, the stator core 9 is axially aligned with the magnetic sheet 8, but there is no requirement for the polarity (it only affects the forward and reverse directions of the current). The output angle range is related to the number of pole pairs. For example, when n=2, the stator core 9 is 2 pairs. There are 4 magnetic sheets 8 in total. At this time, when the present invention is energized, the angle range with torque output is 90°, such as Figure 6 As shown, it can be seen that under the condition of rated current in the torque output range, about 70° range belongs to the range above the rated torque, so when n=2, the effective output angle range is 70°. When n=3, there are 3 pairs of stator cores 9. There are 6 magnetic sheets 8. At this time, when the limited angle torque motor is powered on, the angle range with torque output is 60°. In the torque output range, about 35° range belongs to the range above the rated torque, so when n=3, the effective output angle range is 35°.

[0044] The present invention is also provided with a controller, which includes the following modules: a signal acquisition module: acquires the adjustment command signal and / or the signal reflecting the rotation angle position from the rotation angle sensor 2; a power-on control module: controls the power on of the coil assembly 10 according to the adjustment command signal and / or the signal reflecting the rotation angle position from the rotation angle sensor 2. During use, the torque actuator provided by the present invention first adjusts the angular position of the output shaft 5 according to the adjustment command signal from the operation interface, and the angle sensor outputs the rotation angle position signal to the controller in real time, realizing position closed-loop control and providing control accuracy.

[0045] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various modifications or variations within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other at will.

Claims

1. A torque actuator, characterized in that: It comprises a sealing assembly, a rotor assembly, a stator assembly, an output shaft (5) and a sensor assembly; A container space is formed inside the sealing assembly, and the rotor assembly and the stator assembly are installed in the container space; The rotor assembly comprises a magnetic sheet (8), the stator assembly comprises a stator, and the stator comprises a stator core (9) and a coil assembly (10); the magnetic sheet (8) is located at one end of the stator core (9) along the axial direction; The rotor assembly is tightly connected to the output shaft (5), and the output shaft (5) extends in the axial direction to the outside of the container space; The sensor assembly comprises an eccentric wheel (3) and a rotation angle sensor (2), and the rotor assembly and / or the output shaft (5) are fixedly connected to the eccentric wheel (3); The sealing assembly comprises an outer cover shell (1) and an upper cover plate (4); the outer cover shell (1) and the upper cover plate (4) are tightly connected; The output shaft (5) extends at both ends in the axial direction, respectively passing through the outer housing (1) and the upper cover plate (4) to reach outside the container space; It also includes bearings, wherein the plurality of bearings include a first bearing (6) and a second bearing (12); The output shaft (5) is rotatably connected to the upper cover plate (4) and the outer cover shell (1) through a first bearing (6) and a second bearing (12) respectively; The rotor assembly further comprises a rotor substrate (7), and 2n magnetic sheets (8) are evenly distributed on the rotor substrate (7) along a circumferential direction, wherein n is a positive integer; The extension direction between the two poles of the magnetic sheet (8) NS is parallel to the axial direction of the stator core (9); along the circumferential direction, the magnetic poles of two adjacent magnetic sheets (8) are arranged in opposite directions; The magnetic sheet (8), the rotor substrate (7), and the rotation angle sensor (2) are arranged in sequence along the axial direction of the output shaft (5).

2. The torque actuator according to claim 1, characterized in that: The stator assembly further comprises a stator substrate (11); a plurality of stators are evenly distributed on the stator substrate (11) along a circumferential direction; The number of stators is equal to the number of magnetic sheets (8).

3. The torque actuator according to claim 2, characterized in that: The stator assembly also includes potting (13), wherein the potting (13) fixes the stator and the stator base plate (11) in the container space.

4. The torque actuator according to claim 1, characterized in that: Also included is a controller, which includes the following modules: Signal acquisition module: acquires the adjustment command signal and / or the signal reflecting the rotation angle position from the rotation angle sensor (2); A power-on control module controls the power-on of the coil assembly (10) according to the adjustment command signal and / or the signal reflecting the rotation angle position from the rotation angle sensor (2).

5. The torque actuator according to claim 1, characterized in that: The first bearing (6) and the second bearing (12) are both needle bearings.

6. The torque actuator according to claim 1, characterized in that: The outer cover shell is provided with a bottom boss, and the rotor base plate (7) is installed between the outer wall surface of the bottom boss and the inner wall surface of the outer cover shell (1); An opening is provided at the bottom of the outer cover shell (1), and a fastener passes through the opening to fasten and connect the rotor base plate (7) and the stator core (9).

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