Connecting structure for driving worm shaft to detect magnetic position of motor rotor

Abstract

The utility model discloses a connecting structure for driving a worm shaft to detect the magnetic position of a motor rotor, and belongs to the technical field of steering. The device comprises a torque feedback unit which comprises a motor and a worm shaft, the motor is connected with the worm shaft, and a protruding spline shaft is arranged at the tail end of the worm shaft; the angle position detection unit comprises a sensor assembly and a PCBA (Printed Circuit Board Assembly); the sensor assembly is installed at the head end of the worm shaft, a magnetic position sensor is arranged on the PCBA, and the magnetic position sensor is used for detecting the change of a surrounding magnetic field when the sensor assembly rotates. According to the utility model, the spline shaft is integrally and stably formed at the tail end of the worm shaft, and the structure is the convex spline shaft, so that the space of the tail end of the worm shaft can be fully utilized, and inherent functional parts of the worm shaft cannot be influenced at all.

Description

TECHNICAL FIELD

[0001] The utility model relates to a steering technical field, concretely relates to a connection structure for driving worm shaft detects motor rotor magnetic position. BACKGROUND

[0002] Steering by wire (SbW) is a kind of steering technology, which cancels the mechanical connection between steering wheel and chassis, has the advantages such as fast reaction, comfort, lightness and the like.

[0003] In order to ensure safety, the steering by wire system is provided with a torque feedback unit (TFU), which connects the steering wheel through a steering shaft, and is used to provide resistance torque when the vehicle is steering, so as to simulate road feeling information feedback to the driver.

[0004] The torque feedback unit generates resistance torque through a driving motor, and the torque output by the motor is transmitted to the steering shaft through a worm and a worm wheel.The driving of the motor depends on the high-precision detection and control of the rotor position. After the torque feedback unit is assembled and put into use, the position, rotation angle and speed of the motor rotor need to be detected by the magnetic position sensor in the motor to ensure that the performance of the motor meets the use requirements, and the position detection of the magnetic position sensor is therefore one of the key technologies.

[0005] The current detection method needs a drive to drive the worm shaft and sensor assembly to rotate, and then the magnetic position sensor chip on the PCBA detects the magnetic field change around the sensor assembly when it rotates to determine the angular position of the motor. The usual driving method is to drive the rotation of the worm shaft by adopting the worm and worm gear driving mode, and the worm wheel cooperates with the worm shaft to drive the rotation of the worm shaft and the sensor assembly on the top through the rotation of the worm wheel.

[0006] Because the worm and worm gear driving will directly affect the measurement accuracy of the motor rotor magnetic position due to the manufacturing error, transmission error, thermal expansion error and installation error of the worm wheel and worm shaft, therefore, a mode that can directly drive the worm shaft and sensor assembly is particularly important. INVENTION CONTENTS

[0007] The utility model aims at providing a connection structure for driving worm shaft detects motor rotor magnetic position, which is integrally formed at the tail end of the worm shaft stably, and the structure is a convex spline shaft, which can fully utilize the space of the tail end of the worm shaft and will not affect the inherent functional components of the worm shaft.

[0008] To solve the above technical problems, the utility model provides a connection structure for driving worm shaft detects motor rotor magnetic position, which comprises:

[0009] A torque feedback unit comprises a motor and a worm shaft, the motor is connected with the worm shaft, and a convex spline shaft is arranged at the tail end of the worm shaft;

[0010] An angle position detection unit comprises a sensor assembly and a PCBA; the sensor assembly is installed at the head end of the worm shaft, and a magnetic position sensor is arranged on the PCBA and used for detecting the change of the magnetic field around the sensor assembly when the sensor assembly rotates.

[0011] Preferably, the motor comprises a motor rotor and a motor stator;

[0012] The motor rotor is connected with the worm shaft.

[0013] Preferably, the shell further comprises a housing;

[0014] The motor and the worm shaft are located in the shell.

[0015] Preferably, a housing groove and a housing bearing groove are sequentially arranged from the outside to the inside at the head end of the inside of the shell;

[0016] The motor stator is installed in the housing groove;

[0017] A ball bearing is installed in the housing bearing groove, and the ball bearing is sleeved on the worm shaft.

[0018] Preferably, the worm shaft penetrates through a wave spring;

[0019] The wave spring is installed in the housing bearing groove and located between the ball bearing and the groove wall of the housing bearing groove.

[0020] Preferably, a worm shaft shoulder is arranged on the worm shaft;

[0021] The ball bearing abuts against the worm shaft shoulder.

[0022] Preferably, a housing nut position and a housing bearing position are sequentially arranged from the outside to the inside at the tail end of the inside of the shell;

[0023] A deep groove ball bearing is installed in the housing bearing position, and the deep groove ball bearing is sleeved on the worm shaft;

[0024] A fixed nut and a lock nut are installed in the housing nut position;

[0025] The housing nut position is provided with an internal thread, and the lock nut is provided with an external thread;

[0026] The lock nut is threadedly connected with the housing nut position of the shell and abuts against the position close to the outside of the deep groove ball bearing;

[0027] The fixed nut is located in the lock nut;

[0028] The fixed nut is provided with an internal thread, and the worm shaft is provided with an external thread at a position close to the tail end;

[0029] The fixed nut is threadedly connected with the worm shaft and abuts against a position close to the inner side of the deep groove ball bearing.

[0030] Preferably, the convex spline shaft at the tail end of the worm shaft penetrates through the fixed nut and the lock nut.

[0031] Preferably, the end cap is installed at the first end of the shell, and the PCBA is installed on the end cap.

[0032] The sensor assembly and the worm shaft are coaxially arranged.

[0033] The ECU cover is arranged on the rear end cap.

[0034] Compared with the prior art, the utility model has the beneficial effects that:

[0035] The utility model discloses a convex spline shaft at the tail end of the worm shaft, which can fully utilize the space of the tail end of the worm shaft and does not affect the inherent functional components of the worm shaft. BRIEF DESCRIPTION OF DRAWINGS

[0036] The specific embodiment of the utility model will be further described in detail below with reference to the drawings.

[0037] Figure 1 It is the structure schematic diagram of torque feedback unit;

[0038] Figure 2 It is the explosion schematic diagram of each component position distribution in torque feedback unit;

[0039] Figure 3 It is the structure schematic diagram of motor rotor assembly to worm shaft;

[0040] Figure 4 It is the structure schematic diagram of motor stator 8b and deep groove ball bearing 4 press into shell 3;

[0041] Figure 5 It is the structure schematic diagram of fixed nut 2 and lock nut 1 installation to shell 3;

[0042] Figure 6 It is the structure schematic diagram of sensor assembly 9 coaxial installation in worm shaft 5;

[0043] In the figure: 1 - lock nut; 2 - fixing nut; 3 - housing; 3a - housing groove; 3b - housing bearing groove; 3c - housing bearing position; 3d - housing nut position; 4 - deep groove ball bearing; 5 - worm shaft; 5a - convex spline shaft; 6 - wave spring; 7 - ball bearing; 8 - motor; 8a - motor rotor; 8b - motor stator; 9 - sensor assembly; 10 - rear end cover; 11 - PCBA; 12 - ECU cover. DETAILED DESCRIPTION

[0044] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, it will be apparent to one skilled in the art that the present application can be practiced without the specific details presented herein. In other instances, well-known methods have not been described in detail in order to avoid obscuring the present application. Therefore, the present application is not intended to be limited by the specific embodiments disclosed below, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0045] The terminology used in this description of one or more embodiments should not be taken as limiting. Throughout this description, singular forms such as "a," "an," and "the" include plural references unless the context clearly dictates otherwise. Portions of the description of one or more embodiments have been presented in terms of procedures, logic blocks, processing and other symbolic representations of operations on data bits that serve to convey the substance of their actions, their results, and operations associated therewith. These descriptions and representations are used by those skilled in the art to most effectively convey the substance of their work to others skilled in the art. In the interests of brevity and clearness, not all of the detailed information referred to by a specific term is incorporated in a specific instance.

[0046] It is to be understood that the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. It is to be further understood that the terms "and / or" and "one or more of the following" include any and all combinations of one or more of the associated listed items.

[0047] The present application will be further described with reference to the drawings, wherein:

[0048] The present application provides a kind of for driving worm shaft detection motor rotor magnetic position connection structure, comprising:

[0049] Torque feedback unit, it includes motor 8 and worm shaft 5, the motor 8 is connected with worm shaft 5, the worm shaft 5 tail end is provided with convex spline shaft 5a;

[0050] An angle position detection unit comprising a sensor assembly 9 and a PCBA 11; the sensor assembly 9 is installed at the front end of the worm shaft 5, and the PCBA 11 is provided with a magnetic position sensor for detecting the change of the magnetic field around the sensor assembly 9 when it rotates.

[0051] Preferably, the motor 8 comprises a motor rotor 8a and a motor stator 8b;

[0052] The motor rotor 8a is connected with the worm shaft 5.

[0053] Preferably, it further comprises a housing 3;

[0054] The motor 8 and the worm shaft 5 are both located in the housing 3.

[0055] Preferably, the inside of the housing 3 is sequentially provided with a housing groove 3a and a housing bearing groove 3b from the outside to the inside at the front end;

[0056] The motor stator 8b is installed in the housing groove 3a;

[0057] A ball bearing 7 is installed in the housing bearing groove 3b, and the ball bearing 7 is sleeved on the worm shaft 5.

[0058] Preferably, the worm shaft 5 passes through the wave spring 6;

[0059] The wave spring 6 is installed in the housing bearing groove 3b and located between the ball bearing 7 and the groove wall of the housing bearing groove 3b.

[0060] Preferably, the worm shaft 5 is provided with a worm shaft shoulder;

[0061] The ball bearing 7 abuts against the worm shaft shoulder.

[0062] Preferably, the inside of the housing 3 is sequentially provided with a housing nut position 3d and a housing bearing position 3c from the outside to the inside at the tail end;

[0063] A deep groove ball bearing 4 is installed in the housing bearing position 3c, and the deep groove ball bearing 4 is sleeved on the worm shaft 5;

[0064] A fixed nut 2 and a lock nut 1 are installed in the housing nut position 3d;

[0065] The housing nut position 3d is provided with an internal thread, and the lock nut 1 is provided with an external thread;

[0066] The lock nut 1 is threadedly connected with the housing nut position 3d of the housing 3 and abuts against the position close to the outside of the deep groove ball bearing 4;

[0067] The fixed nut 2 is located in the lock nut 1.

[0068] The fixed nut 2 is provided with an internal thread, and the worm shaft 5 is provided with an external thread at a position close to the tail end;

[0069] The fixed nut 2 is threadedly connected with the worm shaft 5 and abuts against the deep groove ball bearing 4 at a position close to the inner side.

[0070] Preferably, the protruding spline shaft 5a at the tail end of the worm shaft 5 penetrates through the fixed nut 2 and the lock nut 1.

[0071] Preferably, the housing 3 is provided with an end cover 10 at the head end, and the end cover 10 is provided with a PCBA 11.

[0072] The sensor assembly 9 and the worm shaft 5 are coaxially arranged.

[0073] The ECU cover 12 is arranged on the rear end cover 10.

[0074] In order to better illustrate the technical effect of the utility model, the utility model provides the following specific embodiment to illustrate the above technical process:

[0075] Embodiment 1, a connecting structure for detecting the magnetic rotor position of a motor for directly driving a worm shaft, which is integrally formed at the tail end of the worm shaft and is a protruding spline shaft, can fully utilize the space of the tail end of the worm shaft and will not affect the inherent functional components of the worm shaft.

[0076] Principle of the utility model:

[0077] 1. A torque feedback unit, comprising a lock nut 1, a fixed nut 2, a housing 3, a deep groove ball bearing 4, a worm shaft 5, a protruding spline shaft 5a, a wave spring 6, a ball bearing 7, a motor 8, a motor rotor 8a, a motor stator 8b, a sensor assembly 9, a rear end cover 10, a PCBA 11, an ECU cover 12, as shown in Figure 1 .

[0078] 2. The sensor assembly 9 is arranged at the top of the worm shaft 5 close to the motor 8 side, a magnetic position sensor is arranged on the PCBA 11 above the sensor assembly 9, and the magnetic position sensor on the PCBA 11 determines the angle position of the motor rotor 8a by detecting the magnetic field change around the sensor assembly 9 when the sensor assembly 9 rotates.

[0079] 3. In the traditional driving method, the worm shaft 5 is usually driven to rotate by rotating a worm gear to drive the rotation of the sensor assembly 9. Since the worm gear drive will bring a certain rotation error, it will affect the detection of the torque feedback unit on the motor position sensor signal accuracy.

[0080] 4. A protruding spline shaft 5a for driving is provided at the tail end of the worm shaft 5. The worm shaft 5 can be clamped by an external mechanical device through the protruding spline shaft 5a to transmit stable rotation, so that the magnetic position sensor chip located on PCBA11 can accurately monitor the magnetic field around the sensor assembly 9 when it rotates, thereby ensuring the normal function of the torque feedback unit.

[0081] 5. In this embodiment, a protruding spline shaft 5a is used as a connection structure for driving the worm shaft to detect the magnetic position of the motor rotor. It is clamped by an external mechanical device to accurately control the rotation accuracy. It can avoid various errors caused by the worm gear drive and achieve accurate detection of the magnetic position of the sensor component 9 by the magnetic position sensor without affecting the normal function of the torque feedback unit.

[0082] Specific embodiments of this utility model:

[0083] 1. The torque feedback unit described in this embodiment is applied to a steer-by-wire system, such as... Figure 1 As shown.

[0084] 2. An exploded view showing the positional distribution of various components in the torque feedback unit described in this embodiment, as shown below. Figure 2 As shown.

[0085] 3. The worm shaft 5 has a shoulder and a groove. The ball bearing 7 is installed at the shoulder on one end of the worm shaft 5, and then the motor rotor 8a is assembled onto the worm shaft 5. Figure 3 As shown.

[0086] 4. From the outside to the inside, the inner end of housing 3 is provided with housing groove 3a and housing bearing groove 3b. From the outside to the inside, the inner end of housing 3 is provided with housing nut position 3d and housing bearing position 3c. The motor stator 8b is press-fitted into housing groove 3a, and the deep groove ball bearing 4 is press-fitted into housing bearing position 3c of housing 3. Figure 4 As shown.

[0087] 5. Install the wave spring 6 into the housing 3. The worm shaft 5 passes through the wave spring 6 and the deep groove ball bearing 4 into the housing 3. Tighten the fixing nut 2, then tighten the anti-loosening nut 1 and install it into the housing 3. Figure 5 As shown.

[0088] 6. The rear end cover 10 is installed on the housing 3 near the motor 8. The sensor assembly 9 is coaxially (sharing a common axis Z) mounted on the top of the worm shaft 5 near the motor 8. Figure 6 As shown.

[0089] 7. Install PCBA11 onto the rear end cover 10, and finally install the ECU cover 12 onto the rear end cover 10, as follows. Figure 1 As shown.

[0090] 8. The tail end of the worm shaft 5 is provided with a convex spline shaft 5a as a connecting structure.

[0091] 9. The convex spline shaft 5a is stably formed at the tail end of the worm shaft 5 by integral molding, and an external mechanical device can stably drive the worm shaft 5 by clamping the connecting structure convex spline shaft 5a, so that the magnetic position sensor chip on the PCBA 11 in the motor 8 can accurately detect the magnetic position of the sensor assembly 9.

[0092] 10. In the embodiment, the connecting structure convex spline shaft 5a at the tail end of the worm shaft 5 is used to drive the worm shaft to detect the magnetic position of the motor rotor, and is clamped and driven by the external mechanical device. The connecting structure can fully utilize the space at the tail end of the worm shaft 5 and will not affect the inherent functional components of the worm shaft 5.

[0093] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any change or replacement within the technical scope disclosed by the present application should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A connection structure for driving a worm shaft to detect the magnetic position of a motor rotor, characterized in that, include: The torque feedback unit includes a motor (8) and a worm shaft (5); the motor (8) is connected to the worm shaft (5), and the tail end of the worm shaft (5) is provided with a protruding spline shaft (5a); An angular position detection unit includes a sensor assembly (9) and a PCBA (11); the sensor assembly (9) is installed at the head end of the worm shaft (5), and a magnetic position sensor is provided on the PCBA (11) for detecting changes in the magnetic field around the sensor assembly (9) when it rotates.

2. The connection structure for driving the worm shaft to detect the magnetic position of the motor rotor according to claim 1, characterized in that: The motor (8) includes a motor rotor (8a) and a motor stator (8b); The motor rotor (8a) is connected to the worm shaft (5).

3. The connection structure for driving the worm shaft to detect the magnetic position of the motor rotor according to claim 2, characterized in that, It also includes the casing (3); The motor (8) and the worm shaft (5) are both located inside the housing (3).

4. The connection structure for driving the worm shaft to detect the magnetic position of the motor rotor according to claim 3, characterized in that: The inner end of the housing (3) is provided with a housing groove (3a) and a housing bearing groove (3b) from the outside to the inside; The motor stator (8b) is installed in the housing groove (3a); A ball bearing (7) is installed in the bearing groove (3b) of the housing, and the ball bearing (7) is sleeved on the worm shaft (5).

5. The connection structure for driving the worm shaft to detect the magnetic position of the motor rotor according to claim 4, characterized in that: The worm shaft (5) passes through the wave spring (6); The wave spring (6) is installed in the housing bearing groove (3b) and is located between the ball bearing (7) and the groove wall of the housing bearing groove (3b).

6. The connection structure for driving the worm shaft to detect the magnetic position of the motor rotor according to claim 5, characterized in that: A worm shaft shoulder is provided on the worm shaft (5); The ball bearing (7) abuts against the worm shaft shoulder.

7. The connection structure for driving the worm shaft to detect the magnetic position of the motor rotor according to claim 6, characterized in that: The inner tail end of the housing (3) is provided with a housing nut position (3d) and a housing bearing position (3c) from the outside to the inside; A deep groove ball bearing (4) is installed in the housing bearing position (3c), and the deep groove ball bearing (4) is sleeved on the worm shaft (5); A fixing nut (2) and an anti-loosening nut (1) are installed in the nut position (3d) of the housing; The housing nut position (3d) is provided with internal threads, and the anti-loosening nut (1) is provided with external threads; The anti-loosening nut (1) is threaded to the housing nut position (3d) of the housing (3) and abuts against the deep groove ball bearing (4) near the outer side; The fixing nut (2) is located in the anti-loosening nut (1); The fixing nut (2) is provided with internal threads, and the worm shaft (5) is provided with external threads near the tail end; The fixing nut (2) is threaded to the worm shaft (5) and abuts against the deep groove ball bearing (4) near the inner side.

8. The connection structure for driving the worm shaft to detect the magnetic position of the motor rotor according to claim 7, characterized in that: The protruding spline shaft (5a) at the tail end of the worm shaft (5) passes through the fixing nut (2) and the anti-loosening nut (1).

9. The connection structure for driving the worm shaft to detect the magnetic position of the motor rotor according to claim 8, characterized in that: The housing (3) has an end cap (10) installed at its front end, and a PCBA (11) is installed on the end cap (10); The sensor assembly (9) and the worm shaft (5) are coaxially arranged; The ECU cover (12) is placed on the rear cover (10).

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