Rotor shaft and encoder mounting structure of motor

Abstract

The utility model provides a rotor shaft and encoder mounting structure of a motor, which comprises a motor casing, a motor rotating shaft, a brake protective cover and a motor encoder, the motor rotating shaft, the brake protective cover and the motor encoder are arranged on the motor casing, the brake protective cover is fixed at the rear end of the motor casing, and the motor rotating shaft is rotatably arranged in the motor casing. The rear end of the motor rotating shaft extends into the brake protective cover, a stator of the motor encoder is fixed in the brake protective cover, a rotor of the motor encoder is located at the rear end of the motor rotating shaft, and the motor rotating shaft and the rotor of the motor encoder are detachably and fixedly connected through an encoder adaptive shaft. And the rear end of the encoder adapter shaft is inserted into a rotor center hole of the motor encoder and is matched with the rotor center hole of the motor encoder in shape. The device has good adaptability to a motor rotating shaft, is convenient to disassemble and assemble quickly, and is compatible with encoders of multiple specifications.

Description

Technical Field

[0001] This utility model relates to the field of motor technology, and more specifically, to a rotor shaft and encoder mounting structure for a motor. Background Technology

[0002] In motor control systems, encoders are key components for achieving high-precision position detection and speed feedback. Their installation and positioning accuracy directly determines the control accuracy and operational stability of the motor. The current mainstream installation method adopts a direct connection between the motor shaft and the encoder rotor. Specifically, the two are fixedly connected by bolts passing through the center hole of the encoder rotor and screwing into the axial threaded hole at the end of the motor shaft. This method requires a strict match between the encoder interface and the shaft structure. However, encoders on the market currently have various mechanical interface types, such as tapered interfaces and frustum interfaces. The motor shaft must be designed with a separate adapter structure for different interfaces, making it impossible for a single shaft to be compatible with multiple encoder specifications. This greatly limits the application flexibility of the motor. During equipment upgrades or maintenance, because the encoder and shaft adopt an integrated connection design, the entire shaft assembly must be disassembled and replaced simultaneously when replacing the encoder. This not only significantly increases the cost of spare parts and the downtime for maintenance, but also significantly reduces the efficiency of production line equipment modification. Utility Model Content

[0003] The purpose of this invention is to overcome the defects in the prior art and provide a universally adaptable motor rotor shaft and encoder mounting structure that is easy to assemble and disassemble quickly and is compatible with encoders of multiple specifications.

[0004] To address the aforementioned problems, this utility model provides a rotor shaft and encoder mounting structure for a motor, comprising a motor housing and a motor shaft, a brake guard, and a motor encoder mounted on the motor housing. The brake guard is fixed to the rear end of the motor housing. The motor shaft is rotatably mounted within the motor housing, with its rear end extending into the brake guard. The stator of the motor encoder is fixed within the brake guard, and the rotor of the motor encoder is located at the rear end of the motor shaft. The motor shaft and the rotor of the motor encoder are detachably fixedly connected via an encoder adapter shaft. The rear end of the encoder adapter shaft is inserted into the center hole of the motor encoder rotor and is adapted to the shape of the center hole of the motor encoder rotor.

[0005] Compared with existing technologies, the advantages of this invention are as follows: This invention achieves decoupling between the motor shaft and the encoder rotor through a split design of the encoder adapter shaft. The shape matching mechanism between the rear end of the adapter shaft and the center hole of the encoder rotor (such as a tapered interface, frustum-shaped interface, etc.) directly solves the compatibility problem of different encoder interface types. This design simplifies encoder replacement to the overall disassembly and assembly of the adapter shaft and encoder assembly, without modifying the main structure of the motor shaft. This preserves the structural stability of the shaft body and achieves "one shaft, multiple uses" through modular interface design. Compared with the traditional integrated shaft structure, maintenance only requires disassembling the adapter shaft assembly instead of the entire shaft, significantly reducing disassembly and downtime, while also reducing spare parts inventory costs (only the adapter shaft needs to be stocked, not the entire shaft).

[0006] Specifically, a recessed hole is radially extended outward on one side of the rotor center hole near the encoder adapter shaft. The rear end of the encoder adapter shaft is embedded in the recessed hole and fixedly connected to the rotor of the motor encoder by a first bolt. A threaded hole for the adapter shaft is opened on the end face of the rear end of the encoder adapter shaft. The position of the threaded hole for the adapter shaft corresponds to the rotor center hole on the motor encoder. The first bolt is inserted into the rotor center hole and threadedly connected to the threaded hole for the adapter shaft. The front end of the encoder adapter shaft is inserted into the shaft center hole of the motor shaft and a fixed disk is coaxially fixed thereto. The fixed disk is fixedly connected to the motor shaft by a second bolt. At least two disk body fixing holes are circumferentially distributed on the fixed disk. A shaft threaded hole is opened at the rear end of the motor shaft, which corresponds one-to-one with the disk body fixing holes. The second bolt is inserted into the disk body fixing hole and threadedly connected to the shaft threaded hole. This technical solution achieves a stable connection between the encoder rotor and the encoder adapter shaft by embedding the hole and the rear end of the encoder adapter shaft, combined with the connection between the first bolt and the threaded hole of the encoder adapter shaft. The fixed plate forms a coaxial rigid connection between the front end of the encoder adapter shaft and the motor shaft through the bolt connection structure of multiple plate fixing holes and the threaded hole of the shaft. This structure not only ensures the concentricity of power transmission, but also allows the encoder adapter shaft to be quickly disassembled and replaced through modular design. It is compatible with multiple encoder types by only replacing the encoder adapter shaft with different rear end interfaces, avoiding the high cost problem caused by the replacement of traditional integrated shafts.

[0007] As an improvement, an encoder mounting base is provided inside the brake guard. The encoder mounting base is detachably and fixedly connected to the inner wall of the brake guard. The encoder mounting base includes a fixing plate and annular connecting parts at both ends fixed between the fixing plate and the inner wall of the brake guard. The fixing plate has encoder mounting holes that extend through the front and rear. The stator of the motor encoder is embedded and fixed in the encoder mounting holes. An encoder placement cavity is formed inside the annular connecting parts. An encoder inlet and outlet is provided at the rear end of the brake guard, communicating with the encoder placement cavity. The annular connecting parts are embedded and fixed in the encoder inlet and outlet. With this structure, the combined encoder mounting base formed by the fixing plate and the annular connecting parts achieves precise positioning by embedding the encoder stator into the encoder mounting holes. The detachable connection between the annular connecting parts and the inner wall of the guard, combined with the encoder inlet and outlet design, allows the entire encoder assembly to be removed from the rear end of the guard. During maintenance, there is no need to disassemble the main motor structure or remove the encoder from the encoder mounting base. This design not only enhances the stability of encoder installation but also significantly improves the convenience of maintenance operations through modular assembly.

[0008] As an improvement, the rear end of the annular connector extends radially outward and is integrally formed with an annular extension. This annular extension is located on the outer rear end of the brake guard and is fixedly connected to the brake guard via a first screw. The annular extension has at least two circumferentially distributed extension fixing holes. The outer rear end of the brake guard has threaded holes corresponding to the extension fixing holes. The first screw is inserted into the extension fixing holes and threadedly connected to the threaded holes of the guard. With this structure, the annular extension and the rear end of the guard are fixed at multiple circumferential points by the first screw, ensuring both the connection strength between the encoder mount and the guard and enabling quick separation through the external mounting structure. When the encoder needs to be replaced, simply removing the screws from the annular extension allows the entire encoder mount to be removed, avoiding the cumbersome operation of disassembling the internal structure of the guard required by traditional built-in installations, significantly reducing maintenance time.

[0009] As an improvement, the annular extension is equipped with a cover plate for closing the encoder inlet and outlet. The cover plate is detachably fixed to the annular extension by a second screw. The annular extension has at least two threaded holes distributed circumferentially, and the cover plate has insertion holes corresponding to the threaded holes. The second screw is inserted into the insertion holes and threadedly connected to the threaded holes. This technical solution, through the detachable sealing structure of the cover plate and the annular extension, forms a physical isolation barrier in the non-maintenance state, effectively preventing external dust from entering the encoder housing cavity through the encoder inlet and outlet. The peripheral fixing method using the second screw ensures both sealing reliability and maintains the quick disassembly and assembly characteristics consistent with the overall structure. This design achieves protective functions while maintaining convenient maintenance access, and meets conventional dust prevention requirements without the need for additional seals. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the overall structure of Example 1;

[0011] Figure 2 for Figure 1 A sectional view along line AA.

[0012] Figure 3 for Figure 2 Enlarged view of point B in the middle;

[0013] Figure 4 This is a partial structural schematic diagram of Embodiment 1;

[0014] Figure 5 for Figure 4 A cross-sectional view along the CC line;

[0015] Figure 6 This is a bottom view of Embodiment 1;

[0016] Figure 7 for Figure 6 A sectional view along the DD line;

[0017] Figure 8 for Figure 7 Enlarged view at point E in the middle;

[0018] Figure 9 This is a partial structural schematic diagram of Example 2;

[0019] Figure 10 for Figure 9 A cross-sectional view along the FF line.

[0020] Explanation of reference numerals in the attached figures:

[0021] 1. Motor housing; 2. Motor shaft; 21. Shaft center hole; 22. Shaft threaded hole; 3. Brake protective cover; 30. Encoder inlet and outlet; 31. Protective cover threaded hole; 4. Motor encoder; 41. Rotor center hole; 42. Embedded hole; 5. Encoder adapter shaft; 510. Adapter shaft core threaded hole; 6. Fixing disc; 60. Disc fixing hole; 61. First bolt; 62. Second bolt; 7. Encoder mounting base; 71. Fixing plate; 710. Encoder mounting hole; 72. Annular connecting part; 720. Encoder placement cavity; 73. Annular extension part; 731. Extension part fixing hole; 732. Extension part threaded hole; 8. Cover plate; 80. Insertion hole; 81. First screw; 82. Second screw; 91. Tapered connecting part; 92. Adapter shaft center hole. Detailed Implementation

[0022] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.

[0023] Example 1: As Figures 1 to 3 As shown, a rotor shaft and encoder mounting structure for an electric motor includes a motor housing 1 and a motor shaft 2, a brake guard 3, and a motor encoder 4 mounted on the motor housing 1. The brake guard 3 is fixed to the rear end of the motor housing 1. The motor shaft 2 is rotatably mounted inside the motor housing 1, with its rear end extending into the brake guard 3. The stator of the motor encoder 4 is fixed inside the brake guard 3, and the rotor of the motor encoder 4 is located at the rear end of the motor shaft 2. The motor shaft 2 and the rotor of the motor encoder 4 are detachably fixedly connected by an encoder adapter shaft 5. The rear end of the encoder adapter shaft 5 is inserted into the rotor center hole 41 of the motor encoder 4 and is adapted to the shape of the rotor center hole 41 of the motor encoder 4.

[0024] This embodiment achieves decoupling between the motor shaft 2 and the encoder rotor through the split design of the encoder adapter shaft 5. The shape adaptation mechanism (such as matching of tapered interface, frustum-shaped interface, etc.) between the rear end of the adapter shaft and the center hole 41 of the encoder rotor directly solves the compatibility problem of different encoder interface types. This design simplifies the encoder replacement operation to the overall disassembly and assembly of the adapter shaft and the encoder assembly, without modifying the main structure of the motor shaft 2. It not only maintains the structural stability of the shaft body, but also achieves "one shaft for multiple uses" through the modular interface design. Compared with the traditional integrated shaft structure, maintenance only requires disassembly of the adapter shaft assembly instead of the entire shaft, significantly reducing disassembly and assembly workload and downtime, while also reducing spare parts inventory costs (only the adapter shaft needs to be stocked instead of the entire shaft).

[0025] like Figures 3 to 5As shown, a recessed hole 42 is radially extended outward in the rotor center hole 41 near the encoder adapter shaft 5. The rear end of the encoder adapter shaft 5 is embedded in the recessed hole 42 and fixedly connected to the rotor of the motor encoder 4 by a first bolt 61. A threaded hole 510 is provided on the rear end face of the encoder adapter shaft 5, and the position of the threaded hole 510 corresponds to the rotor center hole 41 on the motor encoder 4. The first bolt 61 is inserted into the rotor center hole 41 and threadedly connected to the threaded hole 510. The front end of the encoder adapter shaft 5 is inserted into the shaft center hole 21 of the motor shaft 2 and a fixed disk 6 is coaxially fixed thereto. The fixed disk 6 is fixedly connected to the motor shaft 2 by a second bolt 62. At least two disk body fixing holes 60 are circumferentially distributed on the fixed disk 6. The rear end of the motor shaft 2 is provided with a shaft threaded hole 22 that corresponds one-to-one with the disk body fixing holes 60. The second bolt 62 is inserted into the disk body fixing hole 60 and threadedly connected to the shaft threaded hole 22. This technical solution achieves a stable connection between the encoder rotor and the encoder adapter shaft 5 by embedding the hole 42 into the rear end of the encoder adapter shaft 5, combined with the connection between the first bolt 61 and the threaded hole in the shaft center of the encoder adapter shaft 5. The fixing plate 6 forms a coaxial rigid connection between the front end of the encoder adapter shaft 5 and the motor shaft 2 through the bolt connection structure of multiple plate fixing holes 60 and the threaded hole 22 of the shaft. This structure not only ensures the concentricity of power transmission, but also allows the encoder adapter shaft 5 to be quickly disassembled and replaced through modular design. It is compatible with multiple encoder types by only replacing the encoder adapter shaft 5 with different rear end interfaces, avoiding the high cost problem caused by the replacement of traditional integrated shafts.

[0026] like Figures 6 to 8 As shown, the brake protective cover 3 is provided with an encoder mounting base 7. The encoder mounting base 7 is detachably fixed to the inner wall of the brake protective cover 3. The encoder mounting base 7 includes a fixing plate 71 and an annular connecting part 72 fixed at both ends between the fixing plate 71 and the inner wall of the brake protective cover 3. The fixing plate 71 is provided with an encoder mounting hole 710 that runs through the front and rear. The stator of the motor encoder 4 is embedded and fixed in the encoder mounting hole 710. An encoder placement cavity 720 is formed inside the annular connecting part 72. The rear end of the brake protective cover 3 is provided with an encoder inlet and outlet 30 that communicates with the encoder placement cavity 720. The annular connecting part 72 is embedded and fixed in the encoder inlet and outlet 30. With this structure, the combined encoder mounting base 7 formed by the fixing plate 71 and the annular connecting part 72 achieves precise positioning by embedding the encoder stator into the encoder mounting hole 710. The detachable connection between the annular connecting part 72 and the inner wall of the protective cover, along with the design of the encoder inlet and outlet 30, allows the entire encoder assembly to be completely removed from the rear end of the protective cover. During maintenance, there is no need to disassemble the main structure of the motor or remove the encoder from the encoder mounting base 7. This design not only enhances the stability of encoder installation but also significantly improves the convenience of maintenance operations through modular assembly.

[0027] like Figure 8 As shown, the rear end of the annular connecting part 72 extends radially outward to form an integrally formed annular extension part 73. The annular extension part 73 is located on the outer side of the rear end of the brake protective cover 3 and is fixedly connected to the brake protective cover 3 by a first screw 81. The annular extension part 73 has at least two extension part fixing holes 731 distributed circumferentially. The outer side of the rear end of the brake protective cover 3 is provided with a protective cover threaded hole 31 corresponding to the extension part fixing holes 731. The first screw 81 is inserted into the extension part fixing hole 731 and threadedly connected to the protective cover threaded hole 31. With this structure, the annular extension part 73 and the rear end of the protective cover are fixed at multiple points circumferentially by the first screw 81, which not only ensures the connection strength between the encoder mounting base 7 and the protective cover, but also allows for quick separation through the external installation structure. When the encoder needs to be replaced, the encoder mounting base 7 can be removed as a whole simply by removing the screws of the annular extension part 73, avoiding the cumbersome operation of disassembling the internal structure of the protective cover required by the traditional built-in installation, and greatly shortening the maintenance time.

[0028] like Figure 8 As shown, the annular extension 73 is provided with a cover plate 8 for closing the encoder inlet / outlet 30. The cover plate 8 is detachably fixed to the annular extension 73 by a second screw 82. The annular extension 73 has at least two extension threaded holes 732 distributed circumferentially. The cover plate 8 has insertion holes 80 corresponding to the extension threaded holes 732. The second screw 82 is inserted into the insertion holes 80 and threadedly connected to the extension threaded holes 732. This technical solution, through the detachable closed structure of the cover plate 8 and the annular extension 73, forms a physical isolation barrier in the non-maintenance state, effectively preventing external dust from entering the encoder housing cavity 720 through the encoder inlet / outlet 30. The peripheral fixing method of the second screw 82 ensures both sealing reliability and maintains the quick disassembly and assembly characteristics consistent with the overall structure. This design achieves the protective function while maintaining the convenience of the maintenance channel, and meets the conventional dust prevention requirements without the need for additional seals.

[0029] Example 2: This example is based on Example 1, but differs from Example 1 in that the fixing method of the motor encoder 4 and the encoder adapter shaft 5 is different.

[0030] like Figure 9 and Figure 10As shown, a central hole 92 is provided on the rear end face of the encoder adapter shaft 5. The central hole 92 is located in the middle of the rear end face. A tapered connecting part 91 is integrally formed on the front end of the rotor of the motor encoder 4. The tapered connecting part 91 has a tapered structure that gradually narrows from back to front at the front end of the rotor of the motor encoder 4. After the tapered connecting part 91 is inserted into the central hole 92 of the adapter shaft, it is interference-fitted with the hole wall of the central hole 92. This structure realizes a detachable connection structure between the motor encoder 4 and the encoder adapter shaft 5, which has the advantages of simple structure and convenient disassembly and assembly.

[0031] Although the disclosure is as stated above, the scope of protection of this disclosure is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of this disclosure, and all such changes and modifications will fall within the protection scope of this utility model.

Claims

1. A rotor shaft and encoder mounting structure for an electric motor, comprising a motor housing (1) and a motor shaft (2), a brake guard (3), and a motor encoder (4) disposed on the motor housing (1), wherein the brake guard (3) is fixed to the rear end of the motor housing (1), the motor shaft (2) is rotatably disposed within the motor housing (1), the rear end of the motor shaft (2) extends into the interior of the brake guard (3), the stator of the motor encoder (4) is fixed within the brake guard (3), and the rotor of the motor encoder (4) is located at the rear end of the motor shaft (2), characterized in that: The motor shaft (2) and the rotor of the motor encoder (4) are detachably fixedly connected by an encoder adapter shaft (5). The rear end of the encoder adapter shaft (5) is inserted into the rotor center hole (41) of the motor encoder (4) and is adapted to the shape of the rotor center hole (41) of the motor encoder (4).

2. The rotor shaft and encoder mounting structure of the motor according to claim 1, characterized in that: An insert (42) is provided radially outward on one side of the rotor center hole (41) near the encoder adapter shaft (5). The rear end of the encoder adapter shaft (5) is inserted into the insert (42) and fixedly connected to the rotor of the motor encoder (4) by a first bolt (61). A threaded hole (510) is provided on the rear end face of the encoder adapter shaft (5). The threaded hole (510) corresponds to the rotor center hole (41) on the motor encoder (4). The first bolt (61) is inserted into the rotor center hole (41) and threaded with the adapter shaft. The encoder adapter shaft (5) is threaded and connected to the motor shaft (2). The front end of the encoder adapter shaft (5) is inserted into the shaft center hole (21) of the motor shaft (2) and a fixed plate (6) is fixedly fixed thereon. The fixed plate (6) and the motor shaft (2) are fixedly connected by a second bolt (62). At least two plate fixing holes (60) are distributed around the fixed plate (6). The rear end of the motor shaft (2) is provided with a shaft thread hole (22) that corresponds one-to-one with the plate fixing hole (60). The second bolt (62) is inserted into the plate fixing hole (60) and threadedly connected to the shaft thread hole (22).

3. The rotor shaft and encoder mounting structure of the motor according to claim 2, characterized in that: The brake guard (3) is provided with an encoder mounting base (7). The encoder mounting base (7) is detachably fixed to the inner wall of the brake guard (3). The encoder mounting base (7) includes a fixing plate (71) and an annular connecting part (72) with both ends fixed between the fixing plate (71) and the inner wall of the brake guard (3). The fixing plate (71) is provided with an encoder mounting hole (710) that runs through the front and back. The stator of the motor encoder (4) is embedded and fixed in the encoder mounting hole (710). An encoder placement cavity (720) is formed inside the annular connecting part (72). The rear end of the brake guard (3) is provided with an encoder inlet and outlet (30) that communicates with the encoder placement cavity (720). The annular connecting part (72) is embedded and fixed in the encoder inlet and outlet (30).

4. The rotor shaft and encoder mounting structure of the motor according to claim 3, characterized in that: The rear end of the annular connecting part (72) extends radially outward and is integrally formed with an annular extension part (73). The annular extension part (73) is located on the outer side of the rear end of the brake guard (3) and is fixedly connected to the brake guard (3) by a first screw (81). The annular extension part (73) is provided with at least two extension part fixing holes (731) distributed circumferentially. The outer side of the rear end of the brake guard (3) is provided with a guard thread hole (31) corresponding to the extension part fixing hole (731). The first screw (81) is inserted into the extension part fixing hole (731) and threadedly connected to the guard thread hole (31).

5. The rotor shaft and encoder mounting structure of the motor according to claim 4, characterized in that: The annular extension (73) is provided with a cover plate (8) for closing the encoder inlet and outlet (30). The cover plate (8) is detachably fixed to the annular extension (73) by a second screw (82). The annular extension (73) is provided with at least two extension threaded holes (732) distributed circumferentially. The cover plate (8) is provided with a socket (80) corresponding to the extension threaded hole (732). The second screw (82) is inserted into the socket (80) and threadedly connected to the extension threaded hole (732).

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