DD motor

Abstract

The utility model relates to the technical field of motors, in particular to a DD motor. Comprising a rotor assembly, a stator assembly, an encoder assembly and an independent crossed cylindrical roller bearing, the rotor assembly is used for fixing the outer ring of the crossed cylindrical roller bearing; the stator assembly is used for fixing an inner ring of the crossed cylindrical roller bearing; the encoder assembly detects the speed and the position of the rotor and feeds the speed and the position back to the controller, so that a closed-loop control structure is achieved, the size of the motor is reduced, the power density of the motor is improved, the motor is suitable for occasions with small installation space, the motor has high mechanical precision and high bearing capacity, and the axial and radial runout of the motor can reach within 10 microns. And the effect of bearing axial and radial loads of more than 2000kgf can be achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of motors, and in particular to a DD motor. Background Art

[0002] With the continuous advancement of science and technology and the continuous expansion of application fields, servo motors are often used to drive reduction mechanisms in some high-precision, low-speed and high-torque situations. However, there is backlash in gear transmission. When reversing during small and rapid movements, the load and motor may be instantly separated, which will cause unstable control. Conventional outer rotor brushless motors cannot meet the requirements of integration and miniaturization. The motors are too large and are not suitable for occasions with small installation spaces. Utility Model Content

[0003] The purpose of this utility model is to provide a DD motor to address the defects in the existing technology, thereby reducing the size of the motor and improving the power density of the motor. It is suitable for occasions with small installation space, has high mechanical precision and high load-bearing capacity, and the axial and radial runout of the motor can reach within 10um, and can withstand axial and radial loads of more than 2000kgf.

[0004] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a DD motor, including a rotor assembly, a stator assembly, an encoder assembly and a separate cross cylindrical roller bearing; the rotor assembly fixes the outer ring of the cross cylindrical roller bearing; the stator assembly fixes the inner ring of the cross cylindrical roller bearing; the encoder assembly detects the rotor speed and position, and feeds back to the controller to achieve closed-loop control.

[0005] Furthermore, the rotor assembly has a retaining ring groove on the rotor cup, and uses a hole retaining ring and a rear end cover to fix the outer ring of the cross cylindrical roller bearing.

[0006] Furthermore, the stator assembly is machined with external threads on the stator bracket and corresponding nuts are used to axially and radially position and fix the inner ring of the cross cylindrical roller bearing.

[0007] Furthermore, the encoder assembly is installed in the inner cavity of the stator bracket.

[0008] Furthermore, magnetic beads or a code disk are installed at the rear end of the rotor assembly.

[0009] Furthermore, the height difference between the blind hole and the reinforcing ribs is used to form a fan-like structure inside the motor rotor cup, thereby reducing the temperature rise of the motor and improving the efficiency of the motor.

[0010] Furthermore, a ventilation hole is provided below the rear end cover.

[0011] The invention comprises a rotor assembly, a stator assembly, an encoder assembly and a separate cross cylindrical roller bearing; the rotor assembly fixes the outer ring of the cross cylindrical roller bearing; the stator assembly fixes the inner ring of the cross cylindrical roller bearing; the encoder assembly detects the rotor speed and position and feeds back to the controller to achieve a closed-loop control structure, thereby reducing the size of the motor and improving the power density of the motor. The invention is suitable for occasions with small installation space, has high mechanical precision and high load-bearing capacity, and the axial and radial runout of the motor can reach within 10um, and can withstand axial and radial loads of more than 2000kgf. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0013] Figure 1 A cross-sectional view of a DD motor;

[0014] Figure 2 is a schematic diagram of a partial cross-section of a DD motor;

[0015] Figure 3 A schematic diagram of a fan-like structure of a DD motor;

[0016] Figure 4 A cross-sectional view of a fan-like structure of a DD motor;

[0017] Reference numerals:

[0018] Rotor assembly 1, rotor cup 1-1, hole retaining ring 1-2, rear end cover 1-3, fan-like structure 1-4, ventilation hole 1-5, stator assembly 2, nut 2-2, stator bracket 2-3, encoder assembly 3, cross cylindrical roller bearing 4. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0020] In the description of the present invention, it should be noted that the orientations or positional relationships indicated by “center”, “up”, “down”, “left”, “right”, “vertical”, “horizontal”, “inside” and “outside” are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0021] A DD motor, such as Figure 1 、 2 As shown, it includes a rotor assembly 1, a stator assembly 2, an encoder assembly 3 and a separate cross cylindrical roller bearing 4; the rotor assembly 1 fixes the outer ring of the cross cylindrical roller bearing 4; the stator assembly 2 fixes the inner ring of the cross cylindrical roller bearing 4.

[0022] Specifically, the rotor speed and position are detected by the encoder assembly 3 and fed back to the controller to achieve closed-loop control; the cross cylindrical roller bearing 4 has the advantages of small clearance, high rotation accuracy, strong anti-deformation ability and flexible structural design, so as to achieve a single bearing supporting the rotor; the equipment space is simplified, and the hollow hole routing makes wiring easier; due to the use of cross rollers inside, extremely low axial runout and radial runout can be guaranteed, and at the same time, it has a large load-bearing capacity. The rotor assembly 1 cooperates with the encoder assembly 3 to accurately detect the rotor speed and position in real time, achieve closed-loop control, and ensure high-precision positioning and stability of the system. The stator assembly 2 fixes the inner ring of the cross cylindrical roller bearing 4. This structure innovatively realizes the support of the rotor by a single bearing, greatly simplifies the equipment space, and improves the compactness and integration of the structure. The cross cylindrical roller bearing 4 not only has small clearance, high rotation accuracy, And its unique hollow hole design makes wiring easier, avoiding the complex wiring problems in traditional structures. The cross-cylindrical roller bearing 4 adopts a cross-roller design inside to ensure extremely low axial runout and radial runout. The cross-cylindrical roller bearing 4 has a high load-bearing capacity and can meet the use requirements under various heavy-load conditions, improving the reliability and durability of the equipment. The implementation of the closed-loop control system significantly improves the process accuracy and meets the needs of high-precision processing and manufacturing. The compact structural design allows the DD motor to be easily installed in various equipment, saving valuable space resources and reducing the overall cost of the equipment. The optimized structural design and precise closed-loop control significantly improve the transmission efficiency and reduce energy consumption and operating costs. The innovative hollow hole wiring design makes the installation and maintenance process simpler and faster, reducing maintenance costs and time costs.

[0023] As a preferred embodiment of the above, Figure 2As shown, the rotor assembly 1 has a retaining ring groove on the rotor cup 1-1, and uses a hole retaining ring 1-2 and a rear end cover 1-3 to fix the outer ring of the cross cylindrical roller bearing 4.

[0024] Specifically, by providing a retaining ring groove in the rotor cup 1-1 and using a hole retaining ring 1-2 in conjunction with the rear end cap 1-3, the outer ring of the crossed cylindrical roller bearing 4 is securely fixed. This effectively prevents the bearing from loosening or shifting during operation, ensuring stable rotor operation. The retaining ring groove and hole retaining ring design simplify the bearing installation process. Compared with traditional installation methods, this design eliminates the need for complex tooling and easily secures the bearing, reducing installation difficulty and cost. The precise fit of the hole retaining ring 1-2 and the rear end cap 1-3 ensures the precise positioning of the outer ring of the crossed cylindrical roller bearing 4 within the rotor assembly 1. This high-precision positioning helps reduce transmission errors and improve the transmission accuracy and performance of the entire DD motor. The additional support provided by the rear end cap 1-3 on the bearing outer ring enhances the bearing's load-bearing capacity. This design ensures that the DD motor maintains greater stability and durability when operating under heavy loads or at high speeds. The stable bearing fixation structure ensures smoother operation, reduces vibration and noise, and improves the operational stability and reliability of the equipment.

[0025] As a preferred embodiment of the above, Figure 2 As shown, the stator assembly 2 is processed with external threads on the stator bracket 2 - 3 and the inner ring of the cross cylindrical roller bearing 4 is axially and radially positioned and fixed using a corresponding nut 2 - 2 .

[0026] Specifically, the structure of machining external threads on the stator bracket 2-3 through the stator assembly 2 and using the corresponding nut 2-2 to axially and radially position and fix the inner ring of the cross cylindrical roller bearing 4 further realizes the firm fixation of the inner ring of the cross cylindrical roller bearing 4, again preventing the loosening or displacement of the bearing during operation, ensuring the stable operation of the rotor, and simplifying the installation process of the bearing.

[0027] As a preferred embodiment of the above, Figure 1 As shown, the encoder assembly 3 is installed in the inner cavity of the stator bracket 2-3.

[0028] As a preferred embodiment of the above, Figure 1 As shown, magnetic beads or a code disk are installed at the rear end of the rotor assembly 1.

[0029] Specifically, the encoder assembly can accurately measure the rotation angle and position of the motor. Installing the encoder assembly in the inner cavity of the stator bracket can minimize measurement errors and improve measurement accuracy. The magnetic beads or code disk can move accurately with the rotation of the motor and generate stable electrical signals with the encoder assembly, ensuring that the encoder can accurately measure the rotation angle and position of the motor and improve measurement accuracy.

[0030] As a preferred embodiment of the above, Figure 3 As shown, the height difference between the blind hole and the reinforcing ribs is used to form a fan-like structure 1-4 inside the motor rotor cup 1-1, thereby reducing the temperature rise of the motor and improving the efficiency of the motor.

[0031] Specifically, by utilizing the structural characteristics of the blind hole and the reinforcing ribs, a fan-like structure is formed through the height difference between them. When the motor is running, the rotation of the rotor will drive the fan-like structure to generate airflow, thereby realizing internal heat dissipation of the motor. The design of the fan-like structure can enhance the air flow inside the motor and effectively take away the heat generated during the operation of the motor, thereby reducing the temperature rise of the motor, helping to protect the insulation material of the motor, extending the service life of the motor, and improving the operating stability and reliability of the motor. By reducing the temperature rise of the motor, the motor loss caused by the temperature rise can be reduced, thereby improving the efficiency of the motor. In addition, the design of the fan-like structure also helps to optimize the heat dissipation performance of the motor, so that the motor can still maintain a good operating state under higher loads. By utilizing the structural characteristics inside the rotor cup to form a fan-like structure, effective heat dissipation can be achieved without additional heat dissipation components, thereby simplifying the heat dissipation system of the motor and reducing manufacturing and maintenance costs. The reinforcing ribs not only help to form a fan-like structure, but also enhance the structural strength of the rotor cup, which helps to resist the vibration and impact force generated during the operation of the motor and improve the durability and reliability of the motor.

[0032] As a preferred embodiment of the above, Figure 2 As shown, ventilation holes 1-5 are also provided below the rear end cover 1-3.

[0033] Specifically, through effective heat dissipation, the ventilation holes 1-5 can reduce the loss of the motor caused by overheating, thereby improving the operating efficiency of the motor. The ventilation holes 1-5 are below the rear end cover 1-3 to ensure that the heat dissipation requirements can be met without having a negative impact on other performance of the motor.

[0034] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and improvements are intended to fall within the scope of the present invention. The scope of protection claimed in this invention is defined by the appended claims and their equivalents.

Claims

1. A DD motor, characterized in that: It includes a rotor assembly (1), a stator assembly (2), an encoder assembly (3) and a separate cross cylindrical roller bearing (4); The rotor assembly (1) fixes the outer ring of the cross cylindrical roller bearing (4); The stator assembly (2) fixes the inner ring of the cross cylindrical roller bearing (4).

2. The DD motor according to claim 1, characterized in that: The rotor assembly (1) has a retaining ring groove on the rotor cup (1-1), and uses a hole retaining ring (1-2) and a rear end cover (1-3) to fix the outer ring of the cross cylindrical roller bearing (4).

3. The DD motor according to claim 2, characterized in that: The stator assembly (2) is machined with external threads on a stator bracket (2-3) and uses corresponding nuts (2-2) to axially and radially position and fix the inner ring of the cross cylindrical roller bearing (4).

4. The DD motor according to claim 3, characterized in that: The encoder assembly (3) is installed in the inner cavity of the stator bracket (2-3).

5. The DD motor according to claim 4, characterized in that: The rear end of the rotor assembly (1) is equipped with magnetic beads or a code disc.

6. The DD motor according to claim 2, characterized in that: The rotor cup (1-1) forms a fan-like structure (1-4) by utilizing the height difference between the blind hole and the reinforcing ribs.

7. The DD motor according to claim 6, characterized in that: A ventilation hole (1-5) is also provided below the rear end cover (1-3).

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