Mounting structure of automobile EPS motor rotor position sensor

Abstract

The utility model relates to the technical field of motors, in particular to an installation structure of an automobile EPS motor rotor position sensor, which comprises a rotor position sensor and a rotating shaft, the upper end face of the rotating shaft is longitudinally provided with an installation hole, the rotor position sensor comprises an envelope structure, magnetic steel and a fixing rod, the fixing rod is of a solid structure, and the magnetic steel is sleeved at the upper end of the fixing rod. The magnetic steel and the fixing rod are fixed, the enveloping structure wraps the edge of the upper surface, the outer surface and the lower surface of the magnetic steel and fills the first groove in the surface of the fixing rod, and the lower end of the fixing rod is installed in the installation hole. Compared with the prior art, the rotor position sensor has the advantages that the magnetic steel and the fixing rod are directly fixed and are wrapped by the enveloping structure, so that the whole rotor position sensor is tightly combined and can bear larger centrifugal force and vibration. The structure of the fixing rod is not easy to deform, the combination with the mounting hole is firmer, and the loosening risk of the rotor position sensor is reduced. The utility model has the advantages of compact structure, small volume, convenient installation and high reliability.

Description

Technical Field

[0001] The utility model relates to the technical field of motors, in particular to an installation structure of a rotor position sensor of an automobile EPS motor. Background Art

[0002] The permanent magnet synchronous motor used in the EPS steering system is required to have the advantages of compact structure, good reliability and resistance to shock and vibration.

[0003] A magnet for identifying the rotor position is usually installed on the motor shaft, and the magnet cooperates with the Hall sensor to identify the motor speed.

[0004] like Figure 1 As shown, the EPS motor includes a shell 1, a cover plate 2, a rotor core 3, a stator core 4, a stepped shaft 5, and a bracket-type rotor position sensor 6. The stator core 4 is fixed in the shell 1, the rotor core 3 is installed outside the stepped shaft 5 and is located in the center of the stator core 4, the end of the shell 1 is covered with a cover plate 2, the end of the stepped shaft 5 passes through the cover plate 2, and the bracket-type rotor position sensor 6 is fixed on the step structure 51 at the end of the stepped shaft 5.

[0005] like Figure 2 As shown, the bracket-type rotor position sensor 6 includes a bracket 61 and an annular magnet 62. The inner ring of the bracket 61 is mounted on the step structure 51 at the end of the step shaft 5. The annular magnet 62 is fixed between the inner ring and the outer ring of the bracket 61. The annular magnet 62 cooperates with the Hall sensor to identify the motor speed.

[0006] In order to avoid cracking of the annular magnetic steel 62 during press-fitting, the bracket 61 needs to be very thick, resulting in a larger size and heavier mass of the stepped rotor position sensor 6. At the same time, since the bracket 61 is a hollow ring structure composed of an inner ring and an outer ring, under long-term vibration and high and low temperature conditions, the bracket 61 may be deformed, causing the stepped rotor position sensor 6 to become loose.

[0007] Therefore, it is necessary to design an installation structure for an automotive EPS motor rotor position sensor to make the structure more compact, better resistant to shock and vibration, and reduce the risk of the rotor position sensor loosening. Summary of the invention

[0008] The purpose of the utility model is to overcome the deficiencies of the prior art and provide a mounting structure for a rotor position sensor of an automobile EPS motor, so that the structure is more compact, the impact and vibration resistance is better, and the risk of the rotor position sensor being loosened is reduced.

[0009] In order to achieve the above-mentioned purpose, the utility model is a mounting structure of an automotive EPS motor rotor position sensor, comprising a rotor position sensor and a rotating shaft, wherein an upper end surface of the rotating shaft is longitudinally provided with a mounting hole, the rotor position sensor comprising an envelope structure, a magnetic steel, and a fixing rod, wherein the fixing rod is a solid structure, the magnetic steel is sleeved on the upper end of the fixing rod, and the magnetic steel is fixed to the fixing rod, the envelope structure covers the upper surface edge, the outer surface and the lower surface of the magnetic steel, and fills a groove on the surface of the fixing rod, and the lower end of the fixing rod is installed in the mounting hole.

[0010] A stepped hole is provided at the center of the magnetic steel, a convex structure 1 is provided on the inner surface of the stepped hole, a groove 2 is provided on the outer surface of the fixing rod, and the convex structure 1 is embedded in the groove 2.

[0011] The connection surface between the magnetic steel and the fixing rod is provided with a knurled structure or a spiral groove.

[0012] The fixing rod is interference fit with the mounting hole.

[0013] A knurled structure is provided on the connecting surface between the fixing rod and the mounting hole.

[0014] The inner surface of the envelope structure is provided with a plurality of longitudinally arranged convex strips, and the outer surface of the magnetic steel is provided with a plurality of longitudinally arranged grooves three, and the convex strips are respectively embedded in the corresponding grooves three.

[0015] A second protruding structure is provided at the center of the bottom of the envelope structure, and the second protruding structure is embedded in the first groove.

[0016] The upper end surface of the fixing rod is a press-fitting position.

[0017] The rotating shaft passes through a cover plate covering the end of the shell, a stator core is fixed in the shell, and a rotor core is installed outside the rotating shaft and located in the center of the stator core.

[0018] Compared with the prior art, the utility model directly fixes the magnetic steel to the fixing rod and adopts an envelope structure to cover it, so that the rotor position sensor is tightly combined as a whole and can withstand large centrifugal force and vibration. The structure of the fixing rod is not easy to deform, and the combination with the mounting hole is more firm, reducing the risk of the rotor position sensor loosening. The utility model has the advantages of compact structure, small size, easy installation and high reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of an existing EPS motor.

[0020] Figure 2 It is a structural schematic diagram of the stepped rotor position sensor.

[0021] Figure 3 It is a structural schematic diagram of the utility model.

[0022] Figure 4 It is a structural schematic diagram of the rotor position sensor of the utility model.

[0023] Figure 5 It is a structural schematic diagram of the envelope structure of the rotor position sensor of the utility model.

[0024] Figure 6 It is a cross-sectional view of the magnetic steel of the rotor position sensor of the utility model.

[0025] Figure 7 It is an axonometric view of the magnetic steel of the rotor position sensor of the utility model.

[0026] Figure 8 It is a structural schematic diagram of the fixing rod of the rotor position sensor of the utility model. DETAILED DESCRIPTION

[0027] The utility model is now further described with reference to the accompanying drawings.

[0028] See also Figure 3 The utility model is a mounting structure of a rotor position sensor for an automobile EPS motor, comprising a rotor position sensor and a rotating shaft. The upper end surface of the rotating shaft 7 is longitudinally provided with a mounting hole 71. The rotating shaft 7 passes through a cover plate 2 covering the end of a housing 1. A stator core 4 is fixed in the housing 1. The rotor core 3 is mounted outside the rotating shaft 7 and is located in the center of the stator core 4. Figure 4 The rotor position sensor 8 includes an envelope structure 81, a magnet 82, and a fixed rod 83. The fixed rod 83 is a solid structure. The magnet 82 is sleeved on the upper end of the fixed rod 83, and the magnet 82 is fixed to the fixed rod 83. The envelope structure 81 covers the upper surface edge, outer surface and lower surface of the magnet 82, and fills the groove 831 on the surface of the fixed rod 83. The lower end of the fixed rod 83 is installed in the mounting hole 71.

[0029] See also Figure 6 , Figure 8 A stepped hole is provided at the center of the magnetic steel 82 , a protruding structure 821 is provided on the inner surface of the stepped hole, a groove 832 is provided on the outer surface of the fixing rod 83 , and the protruding structure 821 is embedded in the groove 832 .

[0030] In addition to the fixing method of the protrusion structure 1 821 and the groove 2 832 , a knurling structure or a spiral groove may also be provided on the connecting surface between the magnetic steel 82 and the fixing rod 83 to achieve the fixing of the magnetic steel 82 and the fixing rod 83 .

[0031] The fixing rod 83 and the mounting hole 71 are interference fit to fix the rotor position sensor 8. Alternatively, a knurling structure is provided on the connecting surface of the fixing rod 83 and the mounting hole 71 to fix the fixing rod 83 and the rotating shaft 7.

[0032] The magnetic steel 82 is made of a mixture of neodymium iron boron and resin and has magnetic properties. The fixing rod 83 is made of steel. The envelope structure 81 is made of plastic, steel, copper, aluminum or powder metallurgy. The envelope structure 81 forms the magnetic steel 82, the envelope structure 81 and the fixing rod 83 into a whole rotor position sensor 8. The envelope structure 81 strengthens the bonding strength between the magnetic steel 82 and the fixing rod 83, and at the same time can protect the magnetic steel 82 and prevent the magnetic steel 82 from being damaged. The fixing rod 83 is used as an intermediate connecting piece between the rotating shaft 7 and the magnetic steel 82 to improve the fixing strength of the rotor position sensor 8.

[0033] The upper end surface of the fixing rod 83 is the press-fit position. When the rotor position sensor 8 is installed, the pressure of the press acts on the upper end surface of the fixing rod 83, which can prevent the magnetic steel 82 from being directly stressed and damaged.

[0034] See also Figure 5 , Figure 7 The inner surface of the envelope structure 81 is provided with a plurality of longitudinally arranged convex strips 811, and the outer surface of the magnetic steel 82 is provided with a plurality of longitudinally arranged grooves 822. The convex strips 811 are respectively embedded in the corresponding grooves 822 to prevent the magnetic steel 82 from rotating in the circumferential direction and moving in the axial direction.

[0035] See also Figure 5 , Figure 8 The center of the bottom of the envelope structure 81 is provided with a second protrusion structure 812, which is embedded in the first groove 831. The second protrusion structure 812 is formed in the first groove 831 during the coating process of the envelope structure 81, further improving the connection strength of the envelope structure 81, the magnetic steel 82, and the fixing rod 83.

[0036] In the utility model, the magnetic steel is directly fixed to the fixing rod and is covered by an envelope structure, so that the rotor position sensor is tightly combined as a whole and can withstand large centrifugal forces and vibrations. The structure of the fixing rod is not easy to deform, and the combination with the mounting hole is more firm, reducing the risk of the rotor position sensor loosening. The utility model has the advantages of compact structure, small size, easy installation and high reliability.

Claims

1. An installation structure for a rotor position sensor of an automobile EPS motor, comprising a rotor position sensor and a rotating shaft, characterized in that: The upper end surface of the rotating shaft (7) is longitudinally provided with a mounting hole (71). The rotor position sensor (8) comprises an envelope structure (81), a magnetic steel (82), and a fixing rod (83). The fixing rod (83) is a solid structure. The magnetic steel (82) is sleeved on the upper end of the fixing rod (83), and the magnetic steel (82) and the fixing rod (83) are fixed. The envelope structure (81) covers the upper surface edge, the outer surface and the lower surface of the magnetic steel (82), and fills a groove (831) on the surface of the fixing rod (83). The lower end of the fixing rod (83) is mounted in the mounting hole (71).

2. The mounting structure of the automotive EPS motor rotor position sensor according to claim 1 is characterized in that: The magnetic steel (82) is provided with a stepped hole at its center, and a protruding structure 1 (821) is provided on the inner surface of the stepped hole. A groove 2 (832) is provided on the outer surface of the fixing rod (83), and the protruding structure 1 (821) is embedded in the groove 2 (832).

3. The mounting structure of the automotive EPS motor rotor position sensor according to claim 1 is characterized in that: A knurled structure or a spiral groove is provided on the connection surface between the magnetic steel (82) and the fixing rod (83).

4. The mounting structure of the automotive EPS motor rotor position sensor according to claim 1 is characterized in that: The fixing rod (83) is interference fit with the mounting hole (71).

5. The mounting structure of the automotive EPS motor rotor position sensor according to claim 1 is characterized in that: A knurled structure is provided on the connecting surface between the fixing rod (83) and the mounting hole (71).

6. The mounting structure of the automotive EPS motor rotor position sensor according to claim 1, characterized in that: The inner surface of the envelope structure (81) is provided with a plurality of longitudinally arranged convex strips (811), and the outer surface of the magnetic steel (82) is provided with a plurality of longitudinally arranged grooves three (822), and the convex strips (811) are respectively embedded in the corresponding grooves three (822).

7. The mounting structure of the automotive EPS motor rotor position sensor according to claim 1 is characterized in that: A second protruding structure (812) is provided at the center of the bottom of the envelope structure (81), and the second protruding structure (812) is embedded in the first groove (831).

8. The mounting structure of the automotive EPS motor rotor position sensor according to claim 1, characterized in that: The upper end surface of the fixing rod (83) is a press-fit position.

9. The mounting structure of the automotive EPS motor rotor position sensor according to claim 1, characterized in that: The rotating shaft (7) passes through a cover plate (2) covering the end of the housing (1), a stator core (4) is fixed in the housing (1), and a rotor core (3) is mounted outside the rotating shaft (7) and located in the center of the stator core (4).

Images