Servo control system based on linear Hall sensor

Abstract

The utility model relates to the technical field of permanent magnet synchronous motors, in particular to a servo control system based on a linear Hall sensor, which is characterized in that one end of a motor shaft extending out of a motor rear cover is connected with a magnetic steel seat, induction magnetic steel is arranged on the magnetic steel seat, the motor shaft is connected with a rotor iron core, and the rotor iron core is positioned in a motor casing; the outer side of the motor rear cover is connected with a tail end cover through a first screw, the inner side of the tail end cover is connected with a driving plate through a second screw, the driving plate is provided with two linear Hall devices which are distributed in a 90-degree mode, and the positions of the linear Hall devices correspond to the positions of the induction magnetic steel. Compared with the prior art, the servo control system based on the linear Hall sensor solves the defects that the existing rotor is small in magnetic flux leakage and the linear Hall cannot be installed at the position of a stator notch when the size of a motor is small, and the scheme that the linear Hall and a single-chip driving system are integrated together is utilized, so that the integration degree is high, and small-size application is facilitated.

Description

[Technical field]

[0001] The utility model relates to the technical field of permanent magnet synchronous motors, in particular to a servo control system based on a linear Hall sensor. [Background technology]

[0002] The servo motors and drive systems in the prior art are mostly discrete structures. The permanent magnet synchronous motor adopts concentrated windings, and an incremental or absolute encoder is installed at the tail end, and the system is driven by an external servo driver.

[0003] The patent with authorization announcement number CN103222168B uses a switch Hall and a linear Hall, which are distributed at 90 degrees, and adds a back-electromotive force detection coil to form the position feedback part of the motor. These signals are connected to the driver and the position information is acquired through a dedicated algorithm. This method is difficult to install for low-cost and small brushless motors.

[0004] The patent with the authorization announcement number CN110932514B uses four linear Hall sensors to be regularly distributed on the stator adapter plate, and obtains the rotor position information through the Hall voltage signal output by the linear Hall sensor. This method is suitable for rotors with multi-pole magnetic rings and strong rotor leakage magnetic field, and the linear Hall sensor can be installed in the corresponding position. It is not suitable for motors with small rotor leakage magnetic field.

[0005] The patent with the authorization announcement number CN104038134B uses a high-precision frequency extraction module to extract the fundamental component of the original signal from the output signals of two linear Hall sensors distributed at 90 degrees, and sends it to the rotor position angle calculator to solve the rotor angular position information. This method also requires the leakage magnetic field of the rotor to sense the position of the linear Hall sensor and output a voltage signal containing the position information.

[0006] The patent with the authorization announcement number CN208226797U introduces a hollow cup servo motor system, which uses a magnetic encoder as a position sensing module and integrates the motor drive module into the tail end of the motor, improving the efficiency of the motor and the safety and stability of the signal. The cost of the magnetic encoder is higher than that of the linear Hall.

[0007] Therefore, the prior art has defects and needs to be improved. [Contents of the utility model]

[0008] In order to overcome the above problems, the utility model proposes a servo control system based on a linear Hall sensor which can effectively solve the above problems.

[0009] The utility model provides a technical solution to solve the above technical problems: a servo control system based on a linear Hall sensor is provided, comprising a motor casing, a motor back cover is arranged at one end of the motor casing, bearings are arranged on the inner side of the other end of the motor casing and the inner side of the motor back cover, a motor shaft is connected to the two bearings, one end of the motor shaft extends out from the motor back cover, the end of the motor shaft extending out of the motor back cover is connected to a magnetic steel seat, an induction magnetic steel is arranged on the magnetic steel seat, the induction magnetic steel serves as a magnetic field element, a rotor core is connected to the motor shaft, and the rotor core is located inside the motor casing; a tail end cover is connected to the outer side of the motor back cover, a drive board is connected to the tail end cover, two linear Hall devices distributed at 90° are arranged on the drive board, and the positions of the linear Hall devices correspond to the positions of the induction magnetic steel.

[0010] Preferably, the magnetic steel seat includes a lower support plate, a circle of outer baffle plates are arranged on the periphery of the lower support plate, a circle of inner baffle plates are arranged in the middle of the lower support plate, a slot is formed between the inner baffle plates and the outer baffle plates, and the induction magnetic steel is fixed in the slot.

[0011] Preferably, the induction magnetic steel comprises a magnetic steel ring 191, a through hole is formed in the middle of the magnetic steel ring, the inner baffle passes through the through hole, and the magnetic steel ring is clamped in the clamping groove.

[0012] Preferably, a motor shaft hole is provided in the middle of the inner baffle, and the motor shaft is connected to the motor shaft hole.

[0013] Preferably, the distance between the linear Hall device and the induction magnet is 0.8 mm-1.2 mm.

[0014] Preferably, a positioning protrusion is provided on the side of the motor rear cover, and a positioning notch matching the positioning protrusion is provided at the end of the motor housing, and the positioning protrusion is embedded in the positioning notch.

[0015] Preferably, the tail end cover comprises an end cover bottom plate, an opening is provided in the middle of the end cover bottom plate, and the magnetic steel seat and the induction magnetic steel extend into the tail end cover through the opening.

[0016] Preferably, a circle of end cover side plates are arranged around the end cover bottom plate, a support platform is arranged on the upper inner side of the end cover side plates, and the driving plate is supported on the support platform.

[0017] Preferably, reinforcing ribs are provided on the inner side of the end cover side plate, and positioning columns protruding outward are provided on the upper ends of the reinforcing ribs. Positioning holes matching the positioning columns are provided on the driving plate, and the positioning columns are inserted into the positioning holes.

[0018] Preferably, a stator core is arranged on the inner side wall of the motor housing, a rotor magnet is arranged on the outer side of the rotor core, and the rotor magnet and the rotor core constitute the rotor; a spring is arranged on the side of the rotor away from the motor rear cover, and a copper sleeve is sleeved on the motor shaft.

[0019] Compared with the prior art, the servo control system based on the linear Hall sensor of the utility model solves the shortcomings of the existing rotor leakage magnetic field is small, the linear Hall cannot be installed at the stator slot position when the motor size is small, and the solution integrating the linear Hall with the single-chip drive system has high integration and is convenient for small-volume application; the drive control chip and the linear Hall device are connected through the PCB routing of the drive board, which reduces the intermediate cable connection, reduces the cost and improves the efficiency; it can be controlled by bus or IO and can be used as an execution unit in a distributed system.

Brief Description of the Drawings

[0020] Figure 1 It is a stereogram of the servo control system based on the linear Hall sensor of the utility model;

[0021] Figure 2 It is an axial cross-sectional view of the servo control system based on the linear Hall sensor of the utility model;

[0022] Figure 3 It is an exploded diagram of the servo control system based on the linear Hall sensor of the utility model;

[0023] Figure 4 It is a partial stereogram of the servo control system based on the linear Hall sensor of the utility model;

[0024] Figure 5 This is a structural diagram of a driving board of a servo control system based on a linear Hall sensor of the utility model;

[0025] Figure 6 It is a three-dimensional diagram of the magnetic steel seat of the servo control system based on the linear Hall sensor of the utility model;

[0026] Figure 7 A three-dimensional diagram of the induction magnet of the servo control system based on the linear Hall sensor of the utility model;

[0027] Figure 8 It is a stereoscopic diagram of the tail end cover of the servo control system based on the linear Hall sensor of the utility model. [Specific implementation method]

[0028] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below with reference to the accompanying drawings and implementation examples. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0029] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are limited to relative positions on the specified view rather than absolute positions.

[0030] In addition, in the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0031] See also Figures 1 to 8 The servo control system based on the linear Hall sensor of the utility model comprises a motor housing 7, one end of the motor housing 7 is provided with a motor back cover 3, the inner side of the other end of the motor housing 7 and the inner side of the motor back cover 3 are provided with bearings 15, the two bearings 15 are connected with a motor shaft 11, one end of the motor shaft 11 extends out from the motor back cover 3, and the end of the motor shaft 11 extending out from the motor back cover 3 is connected with a magnetic steel seat 17, the magnetic steel seat 17 is provided with an induction magnetic steel 19, the induction magnetic steel 19 serves as a magnetic field element, the motor shaft 11 is connected with a rotor core 10, and the rotor core 10 is located inside the motor housing 7. The magnetic steel seat 17 ensures that the induction magnetic steel 19 is accurately positioned. The magnetic steel seat 17 is made of non-magnetic conductive material, preferably aluminum.

[0032] The outer side of the motor rear cover 3 is connected to the tail cover 2 through the first screw 4, and the tail cover 2 is connected to the driving board 1 through the second screw 18. The driving board 1 is provided with two linear Hall devices 102 distributed at 90 degrees, and the position of the linear Hall device 102 corresponds to the position of the induction magnetic steel 19. The distance between the linear Hall device 102 and the induction magnetic steel 19 is between 0.8mm and 1.2mm, preferably 1mm, which is conducive to the sensitivity and accuracy of the induction.

[0033] When working, the system calculates the position information of the induction magnet 19 through the voltage signal of the linear Hall, and then indirectly obtains the actual position information of the rotor through the position deviation between the rotor and the induction magnet 19, thereby controlling the motor.

[0034] The magnetic steel seat 17 includes a lower support plate 171, and a circle of outer baffle plates 173 are arranged on the periphery of the lower support plate 171. A circle of inner baffle plates 172 are arranged in the middle of the lower support plate 171. A slot is formed between the inner baffle plates 172 and the outer baffle plates 173, and the induction magnetic steel 19 is fixed in the slot.

[0035] The induction magnet 19 includes a magnet ring 191 , a through hole 192 is formed in the middle of the magnet ring 191 , the inner baffle 172 passes through the through hole, and the magnet ring 191 is clamped in the clamping groove.

[0036] A motor shaft hole 174 is provided in the middle of the inner baffle plate 172 , and the motor shaft 11 is connected to the motor shaft hole 174 .

[0037] A positioning protrusion 31 is provided on the side of the motor rear cover 3, and a positioning notch 71 matching the positioning protrusion 31 is provided at the end of the motor housing 7. The positioning protrusion 31 is embedded in the positioning notch 71, which is conducive to the rapid positioning and installation of the motor rear cover 3, improves the assembly efficiency, and has an anti-fool function.

[0038] The tail end cover 2 includes an end cover bottom plate 201 , and an opening 208 is provided in the middle of the end cover bottom plate 201 . The magnetic steel seat 17 and the induction magnetic steel 19 extend into the tail end cover 2 through the opening 208 .

[0039] A circle of end cover side plates 202 are arranged around the end cover bottom plate 201 , a support platform 203 is arranged on the inner side above the end cover side plates 202 , and the driving plate 1 is supported on the support platform 203 .

[0040] A reinforcing rib 204 is provided on the inner side of the end cover side plate 202, and a positioning column 205 protruding outward is provided on the upper end of the reinforcing rib 204. A positioning hole 103 matching the positioning column 205 is opened on the driving plate 1. The positioning column 205 is inserted into the positioning hole 103, which is conducive to the rapid positioning and installation of the driving plate 1.

[0041] The end cover bottom plate 201 is provided with a first fixing hole 206 , and the first fixing hole 206 is used to connect the first screw 4 .

[0042] A second fixing hole 207 is formed at the upper end of the reinforcing rib 204 , and the second fixing hole 207 is used for connecting the second screw 18 .

[0043] The driving board includes a PCB board 101, on which a power module, a single-chip computer module, a pre-driving module, a three-phase inverter module, an operational amplifier module, and a comparator module are arranged, and the device requirements for all functions of the motor are realized through a single chip.

[0044] The PCB board 101 is provided with a driving control chip, and the driving control chip is connected to the linear Hall device 102 through the PCB wiring of the driving board, which reduces the intermediate cable connection, reduces the cost and improves the efficiency.

[0045] A stator core 8 is disposed on the inner side wall of the motor housing 7, and a rotor magnet 9 is disposed on the outer side of the rotor core 10. The rotor magnet 9 and the rotor core 10 constitute a rotor.

[0046] The motor housing 7 and the motor rear cover 3 are used for installing the bearing 15 and supporting the rotor to ensure that the motor rotor is centered. The bearing 15 guides the motor shaft 11 to rotate and reduces friction. The stator core 8 and the motor housing 7 play a protective role, and the core reduces the eddy current loss of the current.

[0047] A spring 12 is provided on the side of the rotor away from the motor rear cover 3, and a gasket 13 is provided on one side of the spring 12. The gasket 13 is located between the bearing 15 and the spring 12. The gasket 13 is located on the side away from the motor rear cover 3. One end of the spring 12 abuts against the gasket 13, and the other end of the spring 12 abuts against the rotor magnet 9.

[0048] The motor shaft 11 is sleeved with a copper sleeve 16 , which is located on a side close to the motor rear cover 3 , and is located on a side of the bearing 15 in the motor rear cover 3 .

[0049] The spring 12 and the copper sleeve 16 are used to control the motor series quantity and ensure that the rotor is centered.

[0050] The stator core 8 is provided with a winding 6, and one end of the stator core 8 is provided with a wire rack 5, and the wire rack 5 is located on a side close to the motor rear cover 3. The three-phase winding is directly welded on the PCB, which reduces the intermediate cable connection, reduces the cost and improves the efficiency.

[0051] The motor shaft 11 provides torque output for the motor. The winding 6 is supplied with power to generate a rotating magnetic field to drive the rotor to operate. The function of the bobbin 5 is to provide insulation for the winding 6 in the stator core 8.

[0052] Compared with the prior art, the servo control system based on the linear Hall sensor of the utility model solves the shortcomings of the existing rotor leakage magnetic field is small, the linear Hall cannot be installed at the stator slot position when the motor size is small, and the solution integrating the linear Hall with the single-chip drive system has high integration and is convenient for small-volume application; the drive control chip and the linear Hall device are connected through the PCB routing of the drive board, which reduces the intermediate cable connection, reduces the cost and improves the efficiency; it can be controlled by bus or IO and can be used as an execution unit in a distributed system.

[0053] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. Any modifications, equivalent substitutions and improvements made within the concept of the present invention should be included in the patent protection scope of the present invention.

Claims

1. A servo control system based on a linear Hall sensor, characterized in that: The motor housing comprises a motor rear cover at one end of the motor housing, bearings are arranged on the inner side of the other end of the motor housing and the inner side of the motor rear cover, a motor shaft is connected to the two bearings, one end of the motor shaft extends out of the motor rear cover, and the end of the motor shaft extending out of the motor rear cover is connected to a magnetic steel seat, an induction magnetic steel is arranged on the magnetic steel seat, and the induction magnetic steel serves as a magnetic field element, a rotor core is connected to the motor shaft, and the rotor core is located inside the motor housing; The outer side of the motor rear cover is connected to a tail end cover, and the tail end cover is connected to a driving board. Two linear Hall devices distributed at 90 degrees are arranged on the driving board, and the positions of the linear Hall devices correspond to the positions of the induction magnets.

2. The servo control system based on the linear Hall sensor as claimed in claim 1, characterized in that: The magnetic steel seat includes a lower support plate, a circle of outer baffle plates are arranged on the periphery of the lower support plate, a circle of inner baffle plates are arranged in the middle of the lower support plate, a slot is formed between the inner baffle plates and the outer baffle plates, and the induction magnetic steel is fixed in the slot.

3. The servo control system based on the linear Hall sensor as claimed in claim 2, characterized in that: The induction magnetic steel comprises a magnetic steel ring (191), a through hole is formed in the middle of the magnetic steel ring, the inner baffle passes through the through hole, and the magnetic steel ring is clamped in the clamping groove.

4. The servo control system based on the linear Hall sensor as claimed in claim 2, characterized in that: A motor shaft hole is provided in the middle of the inner baffle plate, and the motor shaft is connected in the motor shaft hole.

5. The servo control system based on the linear Hall sensor as claimed in claim 1, characterized in that: The distance between the linear Hall device and the induction magnet is 0.8 mm-1.2 mm.

6. The servo control system based on the linear Hall sensor as claimed in claim 1, characterized in that: A positioning protrusion is arranged on the side of the motor rear cover, and a positioning notch matching the positioning protrusion is arranged at the end of the motor housing, and the positioning protrusion is embedded in the positioning notch.

7. The servo control system based on the linear Hall sensor as claimed in claim 1, characterized in that: The tail end cover comprises an end cover bottom plate, an opening is arranged in the middle of the end cover bottom plate, and the magnetic steel seat and the induction magnetic steel extend into the tail end cover through the opening.

8. The servo control system based on the linear Hall sensor as claimed in claim 7, characterized in that: A circle of end cover side plates is arranged around the end cover bottom plate, a support platform is arranged on the inner side above the end cover side plates, and the driving plate is supported on the support platform.

9. The servo control system based on the linear Hall sensor as claimed in claim 8, characterized in that: The inner side of the end cover side plate is provided with a reinforcing rib, the upper end of the reinforcing rib is provided with a positioning column protruding outward, the driving plate is provided with a positioning hole matching the positioning column, and the positioning column is inserted into the positioning hole.

10. The servo control system based on the linear Hall sensor according to claim 1, characterized in that: A stator core is arranged on the inner side wall of the motor housing, a rotor magnet is arranged on the outer side of the rotor core, and the rotor magnet and the rotor core constitute a rotor; a spring is arranged on the side of the rotor away from the motor rear cover, and a copper sleeve is sleeved on the motor shaft.

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