A high-speed linear motion frameless motor

Abstract

The utility model discloses a kind of frameless motor of high-speed linear motion, it is related to motor technical field, including motor shell, the inside integrated drive assembly of motor shell, transmission and output assembly and brake and feedback assembly, the drive assembly is composed of motor stator, motor rotor and motor mounting seat, the motor stator is inlaid in motor mounting seat, the motor rotor is inlaid in motor stator, the transmission and output assembly include hollow rotating shaft.The utility model inserts frameless motor, ball screw, brake, encoder into same sealing shell, forms rotation-linear homology and makes motor axial length shorten, can be directly embedded in robot joint, battery package and the like narrow space, cancel coupling simultaneously, transmission chain zero backlash, so that repetitive positioning accuracy is greatly improved.

Description

Technical Field

[0001] This utility model relates to the field of motor technology, and in particular to a frameless motor for high-speed linear motion. Background Technology

[0002] In high-end equipment such as collaborative robot joints, CTP / CTC structures for new energy vehicle battery packs, minimally invasive puncture instruments, and semiconductor wafer handling, linear actuators simultaneously face rigid requirements for "short stroke, high thrust, lightweight, fully sealed, and maintenance-free".

[0003] Existing technologies generally employ a split topology of "framed servo motor + coupling + ball screw" or "BLDC motor + synchronous belt + lead screw," resulting in a long axial dimension chain—the motor, coupling, bearing housing, and lead screw support are arranged sequentially, leading to a generally long total length. This makes it impossible to fit into narrow cavities such as robot forearms or automotive chassis battery compartments. Furthermore, the accumulation of transmission errors, coupled with coupling backlash and gearbox backlash, results in poor repeatability and positioning accuracy, failing to meet the requirements of high-end medical and semiconductor industries. Therefore, this invention proposes a frameless motor for high-speed linear motion. Utility Model Content

[0004] The purpose of this invention is to provide a frameless motor for high-speed linear motion, in order to solve the problem mentioned in the background art that the existing linear actuators are generally too long to fit into narrow cavities such as robot forearms and car chassis battery compartments.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a frameless motor for high-speed linear motion, comprising a motor housing, wherein the motor housing integrates a drive assembly, a transmission and output assembly, and a braking and feedback assembly; The drive assembly comprises a motor stator, a motor rotor, and a motor mounting base, wherein the motor stator is embedded in the motor mounting base and the motor rotor is embedded in the motor stator; The transmission and output assembly includes a hollow shaft, inside which is a ball screw assembly. The ball screw assembly includes a nut fixed in the inner wall of the hollow shaft. The inner wall of the nut is provided with a ball screw that has a rolling helical engagement. The outside of the hollow shaft is provided with a support member that supports the operation of the hollow shaft. The braking and feedback assembly includes a spring brake for braking the hollow shaft, and a DISC module assembly for detecting signals is provided on one side of the spring brake; The motor rotor is sleeved on the outer wall of the hollow shaft. A sealing ring is fixedly connected between the motor mounting base and the motor housing. A rear sealing cover is provided at one end of the motor housing. The rear sealing cover is used to encapsulate the above-mentioned assemblies. A connector for the frameless motor is provided on the outer wall of the rear sealing cover.

[0006] Preferably, the support includes a double-row angular contact ball bearing fixed inside the motor housing, an outer ring locking ring of the bearing is fixedly connected to the outer wall of one end of the double-row angular contact ball bearing, an inner ring locking ring of the bearing is fixedly connected to the outer wall of one end of the double-row angular contact ball bearing, a follower centering bearing is fixedly connected to the top of the motor stator, and the follower centering bearing is sleeved on the outer wall of the hollow rotating shaft.

[0007] Preferably, the motor mounting base includes a mounting base fixed inside the motor housing, a mounting top seat is fixedly connected to the top surface of the mounting base by bolts, a waveform adjustment washer is sleeved on the bottom surface of the mounting top seat, and an adjustment distance ring is provided on the top surface of the mounting base.

[0008] Preferably, the braking and feedback assembly further includes a brake extension unit fixed between the spring brake and the motor housing. The brake extension unit includes a sensing chip fixedly connected to the rear sealing cover. The sensing chip is connected to the DISC module assembly via an electrical signal. One side of the rear sealing cover is provided with a module assembly protective cover for protecting the DISC module assembly.

[0009] Preferably, the connector includes a power connector, an encoder connector, and a brake connector fixed to the outer wall of the rear sealing cover.

[0010] Preferably, the motor housing has a hollow shaft flange inside, the top surface of the hollow shaft flange has a fixing screw, the hollow shaft flange is fixedly connected to the motor housing by the fixing screw, and the hollow shaft flange is slidably sleeved on the outer wall of the ball screw.

[0011] The technical effects and advantages of this utility model are as follows: This utility model packs the frameless motor, ball screw, brake and encoder into the same sealed housing, forming a rotation-linear homogeneous body, which shortens the axial length of the motor and can be directly embedded into narrow spaces such as robot joints and battery packs. At the same time, the coupling is eliminated and the transmission chain has zero backlash, which greatly improves the repeatability and positioning accuracy. Attached Figure Description

[0012] Figure 1 This is a three-dimensional structural diagram of the present invention.

[0013] Figure 2 This is an exploded structural diagram of the present invention.

[0014] Figure 3 This is a frontal cross-sectional view of the present invention.

[0015] In the diagram: 1. Motor mounting base; 2. Motor housing; 3. Sealing ring; 4. Motor stator; 5. Ball screw assembly; 51. Hollow shaft flange; 52. Ball screw; 6. Fixing screw; 7. Follower centering bearing; 8. Adjusting distance ring; 9. Motor rotor; 10. Waveform adjusting washer; 101. Mounting base; 102. Mounting top; 11. Double row angular contact ball bearing; 12. Bearing outer ring locking ring; 13. Bearing inner ring locking ring; 14. Spring brake; 15. Brake extension unit; 16. Sensing chip; 17. DISC module assembly; 18. Module assembly protective cover; 19. Rear sealing cover; 20. Hollow shaft; 21. Power connector; 22. Encoder connector; 23. Brake connector. Detailed Implementation

[0016] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0017] This utility model provides, for example Figure 1-3 The frameless motor for high-speed linear motion shown includes a motor housing 2, and the motor housing 2 integrates a drive assembly, a transmission and output assembly, and a braking and feedback assembly. The drive assembly consists of a motor stator 4, a motor rotor 9, and a motor mounting base 1. The motor stator 4 is embedded in the motor mounting base 1, and the motor rotor 9 is embedded in the motor stator 4. The transmission and output assembly includes a hollow shaft 20, inside which is a ball screw assembly 5. The ball screw assembly 5 includes a nut fixed in the inner wall of the hollow shaft 20. The inner wall of the nut is provided with a ball screw 52 that has a rolling helical engagement. The outside of the hollow shaft 20 is provided with a support member that supports the operation of the hollow shaft 20. The braking and feedback assembly includes a spring brake 14 for braking the hollow shaft 20, and a DISC module assembly 17 for detecting signals is provided on one side of the spring brake 14. The motor rotor 9 is sleeved on the outer wall of the hollow shaft 20. A sealing ring 3 is fixedly connected between the motor mounting base 1 and the motor housing 2. A rear sealing cover 19 is provided at one end of the motor housing 2 to encapsulate the above-mentioned assemblies. A frameless motor connector is provided on the outer wall of the rear sealing cover 19. This invention integrates the drive assembly, transmission and output assembly, and braking and feedback assembly into the same sealed housing, forming a rotational-linear homogeneous body. This significantly shortens the axial length, allowing it to be directly embedded in narrow spaces such as robot joints and battery packs. At the same time, it eliminates the coupling / gearbox, achieves zero backlash in the transmission chain, and greatly improves repeatability. Finally, through the triple radial seal of the motor housing 2, the rear sealing cover 19, and the sealing ring 3, the entire machine directly reaches IP65, enabling the device to work for a long time in high-pressure steam, coolant, and dust environments. Furthermore, the spring brake 14 immediately engages in the event of a power failure, preventing the load from sliding down during vertical axis or power-off hovering conditions, thus improving the safety level. Finally, all electrical interfaces of the frameless motor connectors are concentrated on the outer wall of a rear sealing cover 19, making the device plug-and-play and requiring zero wiring and maintenance on site.

[0018] like Figure 2 and Figure 3 As shown, the support includes a double-row angular contact ball bearing 11 fixed inside the motor housing 2. A bearing outer ring locking ring 12 is fixedly connected to the outer wall of one end of the double-row angular contact ball bearing 11. A bearing inner ring locking ring 13 is fixedly connected to the outer wall of one end of the double-row angular contact ball bearing 11. A follower centering bearing 7 sleeved on the outer wall of the hollow rotating shaft 20 is fixedly connected to the top of the motor stator 4. The double-row angular contact ball bearing 11 and the follower centering bearing 7 form a backlash-free rotating pair with positioning at both ends. The double-row angular contact ball bearing 11 can withstand axial thrust of 3000 N and eliminate shaft movement caused by the screw back thrust. In addition, the follower centering bearing 7 compensates for thermal expansion, ensuring that the motor air gap is constant within the range of -40 ℃ to +120 ℃ and the motor efficiency does not decrease. At the same time, after the outer ring locking ring 12 and the inner ring locking ring 13 of the bearing are pre-tightened, the bearing clearance is reduced, which further improves the repeatability accuracy.

[0019] like Figure 2 and Figure 3 As shown, the motor mounting base 1 includes a mounting base 101 fixed inside the motor housing 2. The top surface of the mounting base 101 is fixedly connected to the mounting top seat 102 by bolts. The bottom surface of the mounting top seat 102 is fitted with a waveform adjustment washer 10. The top surface of the mounting base 101 is provided with an adjustment distance ring 8. By clamping a waveform adjustment washer 10 between the mounting base 101 and the mounting top seat 102, and inserting an adjustment distance ring 8 into the shaft system, the waveform adjustment washer 10 provides elastic compensation, the bolt does not loosen under long-term vibration, the thickness of the adjustment distance ring 8 can be replaced, the bearing preload can be adjusted at the assembly site in one go, without the need to repeatedly select shims, and the production line cycle time is shortened.

[0020] like Figure 2 and Figure 3As shown, the braking and feedback assembly also includes a brake extension unit 15 fixed between the spring brake 14 and the motor housing 2. The brake extension unit 15 includes a sensing chip 16 fixedly connected to the rear sealing cover 19. The sensing chip 16 is connected to the DISC module assembly 17 via an electrical signal. One side of the rear sealing cover 19 is provided with a module assembly protective cover 18 for protecting the DISC module assembly 17. The DISC module assembly 17 is a 21BFnuvoDisc module. The brake extension unit 15 makes the spring brake 14, the sensing chip 16, and the DISC module assembly 17 into a sandwich-style stacked structure, which reduces the wall thickness of the extension unit and simultaneously serves as the brake stator, encoder bracket, and rear cover positioning stop, further saving axial space. After the sensor chip 16 is plugged into the DISC module component 17, it directly outputs SSI / incremental signals, eliminating the need for traditional encoder cables and improving electromagnetic compatibility performance.

[0021] like Figure 2 and Figure 3 As shown, the connector includes a power connector 21, an encoder connector 22, and a brake connector 23 fixed to the outer wall of the rear sealing cover 19; the power, encoder, and brake connectors are all integrated on the rear sealing cover 19, and the user only needs to plug in one aviation plug, which reduces the on-site wiring time. The connector and the rear sealing cover 19 are sealed with a radial O-ring, which will not damage the IP65 integrity during maintenance and plugging / unplugging. Different customers can quickly change the connector model (M12, DB9, quick plug) to achieve configuration standardization.

[0022] like Figure 3 As shown, the motor housing 2 has a hollow shaft flange 51 inside, and a fixing screw 6 is provided on the top surface of the hollow shaft flange 51. The hollow shaft flange 51 is fixedly connected to the motor housing 2 by the fixing screw 6, and the hollow shaft flange 51 is slidably sleeved on the outer wall of the ball screw 52. The hollow shaft flange 51 serves as a closed force node for the conversion from rotation to linear motion. The screw's counter-thrust travels through the flange to the hollow shaft, then to the bearing, and finally to the housing, preventing the ball screw 52 from bending. The gap between the inner hole of the hollow shaft flange 51 and the outer diameter of the screw is less than 0.05 mm, forming the first dustproof ring, preventing particles from entering the raceway and greatly extending the nut's lifespan. The hollow shaft flange 51 can be quickly replaced. Customers can replace only the ball screw 52 and the hollow shaft flange 51 according to different lead and diameter requirements, while keeping the motor body unchanged. This platform-based design shortens the R&D cycle.

[0023] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A frameless motor for high-speed linear motion, comprising a motor housing (2), characterized in that: The motor housing (2) integrates a drive assembly, a transmission and output assembly, and a braking and feedback assembly. The drive assembly comprises a motor stator (4), a motor rotor (9), and a motor mounting base (1). The motor stator (4) is embedded in the motor mounting base (1), and the motor rotor (9) is embedded in the motor stator (4). The transmission and output assembly includes a hollow shaft (20). A ball screw assembly (5) is provided inside the hollow shaft (20). The ball screw assembly (5) includes a nut fixed in the inner wall of the hollow shaft (20). The inner wall of the nut is provided with a rolling helical ball screw (52). The hollow shaft (20) is provided with a support member on the outside to support the operation of the hollow shaft (20); the braking and feedback assembly includes a spring brake (14) for braking the hollow shaft (20), and a DISC module assembly (17) for detecting signals is provided on one side of the spring brake (14); the motor rotor (9) is sleeved on the outer wall of the hollow shaft (20), and a sealing ring (3) is fixedly connected between the motor mounting base (1) and the motor housing (2). A rear sealing cover (19) is provided at one end of the motor housing (2), and the rear sealing cover (19) is used to encapsulate the above-mentioned assemblies. A connector for a frameless motor is provided on the outer wall of the rear sealing cover (19).

2. The frameless motor for high-speed linear motion according to claim 1, characterized in that: The support includes a double-row angular contact ball bearing (11) fixed inside the motor housing (2). A bearing outer ring locking ring (12) is fixedly connected to the outer wall of one end of the double-row angular contact ball bearing (11). A bearing inner ring locking ring (13) is fixedly connected to the outer wall of one end of the double-row angular contact ball bearing (11). A follower centering bearing (7) is fixedly connected to the top of the motor stator (4). The follower centering bearing (7) is sleeved on the outer wall of the hollow rotating shaft (20).

3. A frameless motor for high-speed linear motion according to claim 1, characterized in that: The motor mounting base (1) includes a mounting base (101) fixed inside the motor housing (2). The top surface of the mounting base (101) is fixedly connected to a mounting top seat (102) by bolts. A waveform adjustment washer (10) is sleeved on the bottom surface of the mounting top seat (102). An adjustment distance ring (8) is provided on the top surface of the mounting base (101).

4. A frameless motor for high-speed linear motion according to claim 1, characterized in that: The braking and feedback assembly also includes a brake extension unit (15) fixed between the spring brake (14) and the motor housing (2). The brake extension unit (15) includes a sensing chip (16) fixedly connected to the rear sealing cover (19). The sensing chip (16) is connected to the DISC module assembly (17) via an electrical signal. One side of the rear sealing cover (19) is provided with a module assembly protective cover (18) for protecting the DISC module assembly (17).

5. A frameless motor for high-speed linear motion according to claim 1, characterized in that: The connector includes a power connector (21), an encoder connector (22), and a brake connector (23) fixed to the outer wall of the rear sealing cover (19).

6. A frameless motor for high-speed linear motion according to claim 1, characterized in that: The motor housing (2) is provided with a hollow shaft flange (51) inside. The top surface of the hollow shaft flange (51) is provided with a fixing screw (6). The hollow shaft flange (51) is fixedly connected to the motor housing (2) by the fixing screw (6). The hollow shaft flange (51) is slidably sleeved on the outer wall of the ball screw (52).

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