Motor bearing pre-tightening force accurate control mechanism and motor

Abstract

This utility model relates to a precise control mechanism for the preload of a motor bearing and a motor. The precise control mechanism for the preload of a motor bearing includes an energized coil electromagnet, a housing, a spring, a pressure load sensor, a push rod, and a pressure plate. The energized coil electromagnet is fixed to one end of the housing, and the pressure plate is fixed to the other end of the housing. The push rod is slidably disposed inside the housing, and a pressure load sensor and a spring are sleeved on the push rod. One end of the spring abuts against the energized coil electromagnet, and the other end abuts against the pressure load sensor. Under the action of the spring, the end of the push rod protrudes through the pressure plate. This utility model uses the spring to press the push rod against the bearing to achieve initial preload. The pressure load sensor is directly embedded in the force transmission path to monitor the actual preload in real time. By controlling the energized coil electromagnet, the push rod is moved closer to or away from the energized coil electromagnet, thereby achieving high-precision closed-loop adjustment of the preload.

Description

Technical Field

[0001] This utility model belongs to the field of motor structure technology, and in particular relates to a precise control mechanism for motor bearing preload and a motor. Background Technology

[0002] Precise control of motor bearing preload is a key technology for ensuring motor operation stability, reducing vibration and noise, and extending bearing life. Traditional preload adjustment mechanisms mainly rely on passive methods such as mechanical shims, threaded tightening, or wave springs, which have the following inherent defects: 1. Low adjustment accuracy: Preload depends on manual assembly experience and cannot achieve dynamic compensation. It is easy for the preload to deviate from the design value due to bearing wear or thermal deformation; 2. Lack of closed-loop feedback: There is a lack of real-time force monitoring mechanism. When the preload exceeds the limit, it is easy to cause bearing overheating or premature failure; 3. Complex structure: It requires stopping the machine for disassembly and adjustment, which is difficult to meet the real-time control requirements of high-speed motors or variable operating conditions. Utility Model Content

[0003] To solve the above-mentioned technical problems, the first objective of this utility model is to provide a precise control mechanism for the preload of motor bearings, and the second objective of this utility model is to provide a motor.

[0004] To achieve the first objective of this utility model, the present utility model adopts the following technical solution: A precise control mechanism for the preload of a motor bearing includes an energized coil electromagnet, a housing, a spring, a pressure load sensor, a push rod, and a pressure plate. The energized coil electromagnet is fixed to one end of the housing, and the pressure plate is fixed to the other end of the housing. The push rod is slidably disposed inside the housing. The pressure load sensor and the spring are sleeved on the push rod. One end of the spring abuts against the energized coil electromagnet, and the other end abuts against the pressure load sensor. Under the action of the spring, the end of the push rod protrudes through the pressure plate.

[0005] As a preferred embodiment, the end of the push rod is provided with multiple clamping posts at equal intervals along the circumference, and the clamping posts penetrate the pressure plate.

[0006] As a preferred embodiment, both the outer casing and the push rod are convex in shape, and a gap is left between the first stepped surface of the push rod and the end of the outer casing.

[0007] As a preferred embodiment, the gap between the energized coil electromagnet and the push rod is greater than the gap between the first step surface of the push rod and the end of the housing.

[0008] As a preferred embodiment, the push rod is further provided with a second stepped surface in the middle, and the pressure load sensor is sleeved on the push rod and abuts against the second stepped surface.

[0009] To achieve the second objective mentioned above, this utility model adopts the following technical solution: An electric motor includes a motor housing, a stator assembly, a rotor core, and a shaft. Motor end caps A and B are fixed to both ends of the motor housing, respectively. The stator assembly is fixed to the inner wall of the motor housing. The rotor core is fixed to the shaft, and both ends of the shaft are rotatably connected to motor end caps A and B via bearings. A precise control mechanism for the preload of the motor bearing, as described above, is also fixed to motor end cap A or motor end cap B, with a push rod pressing against the bearing.

[0010] As a preferred embodiment, the motor end cover A or the motor end cover B is provided with a positioning protrusion ring, and the end of the outer shell away from the electromagnet of the energized coil is also provided with a retaining ring, which is sleeved and fixed on the positioning protrusion ring.

[0011] Compared with the prior art, the beneficial effects of this utility model are as follows: This invention uses a spring to press the push rod against the bearing to achieve initial preload. A pressure load sensor is directly embedded in the force transmission path to monitor the actual preload in real time. By controlling the energized coil electromagnet, the push rod is moved closer to or away from the energized coil electromagnet, thereby achieving high-precision closed-loop adjustment of the preload.

[0012] This utility model integrates an electromagnetic actuator (electromagnet), a force sensor, an elastic element (spring), and a force transmission mechanism (push rod) into a single housing, forming a modular unit with a compact overall structure, high axial space utilization, and easy integration into the motor end cover. Furthermore, the sliding push rod design ensures that axial force can be efficiently and accurately transmitted to the bearing. Attached Figure Description

[0013] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute a limitation thereof.

[0014] Figure 1 This is a schematic diagram of the motor structure of this utility model; Figure 2 This is a schematic diagram of the cross-sectional structure of the motor of this utility model; Figure 3 This is an exploded structural diagram of the motor bearing preload precision control mechanism of this utility model; Figure 4 This is a cross-sectional structural schematic diagram of the motor bearing preload precision control mechanism of this utility model.

[0015] The attached figures are labeled as follows: 1. Electromagnet with energized coil; 2. Housing; 3. Spring; 4. Pressure load sensor; 5. Push rod; 6. Pressure plate; 100. Motor housing; 200. Stator assembly; 300. Rotor core; 400. Shaft; 500. Motor end cover A; 600. Motor end cover B; 700. Bearing. Detailed Implementation

[0016] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0017] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0018] Furthermore, in the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0019] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more, unless otherwise expressly defined.

[0020] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0021] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments: like Figures 1 to 4 As shown, an electric motor includes a motor housing 100, a stator assembly 200, a rotor core 300, and a shaft 400. Motor end covers A500 and B600 are fixed to both ends of the motor housing 100, respectively. The stator assembly 200 is fixed to the inner wall of the motor housing 100. The rotor core 300 is fixed to the shaft 400. Both ends of the shaft 400 are rotatably connected to the motor end covers A500 and B600 via bearings 700, respectively. Motor bearing preload is also fixed to either the motor end cover A500 or the motor end cover B600. A force precision control mechanism includes an energized coil electromagnet 1, a housing 2, a spring 3, a pressure load sensor 4, a push rod 5, and a pressure plate 6. The energized coil electromagnet 1 is fixed to one end of the housing 2, and the pressure plate 6 is fixed to the other end of the housing 2. The push rod 5 is slidably disposed inside the housing 2. The pressure load sensor 4 and the spring 3 are sleeved on the push rod 5. One end of the spring 3 abuts against the energized coil electromagnet 1, and the other end abuts against the pressure load sensor 4. Under the action of the spring 3, the end of the push rod 5 protrudes through the pressure plate 6 and presses against the bearing 700.

[0023] In the aforementioned structure, the spring provides an initial, constant preload, which is applied to the bearing via the push rod. This ensures the bearing has the necessary preload during motor startup and basic operation. The force transmission path is spring, pressure sensor, push rod, and bearing. This series design allows the pressure sensor to directly and in real-time measure the actual preload applied to the bearing with high accuracy and independence from interference from other structures. Simultaneously, the sliding design of the push rod provides the physical basis for controlling the electromagnet current based on sensor feedback signals. The electromagnetic force dynamically changes the spring compression (thus changing the preload), achieving closed-loop automatic adjustment of the preload.

[0024] The motor end cover A500 or B600 is provided with a positioning protrusion ring, and the end of the outer shell 2 away from the electromagnet 1 with the energized coil is also provided with a retaining ring, which is sleeved and fixed on the positioning protrusion ring. This structure allows the bearing preload control mechanism to be modularly designed, facilitating production, testing, and replacement as an independent module, thus improving maintainability. Furthermore, the cooperative design of the positioning protrusion ring and the retaining ring allows the control mechanism to be quickly and accurately installed at the designated position on the motor end cover, ensuring that the axis of the push rod is aligned with the bearing axis and guaranteeing the correct direction of the applied preload.

[0025] In addition, the socket mounting method can also be used in conjunction with screws or clips for fixation, providing sufficient connection strength and rigidity to prevent the control mechanism from loosening or shifting during operation. At the same time, this end-face mounting method typically facilitates the design of sealing structures (such as O-rings) to prevent external dust and oil from entering the control mechanism or motor.

[0026] Multiple clamping posts are equidistantly spaced along the circumference at the end of the push rod 5, and the clamping posts penetrate the pressure plate 6. The multiple clamping posts are equidistantly distributed circumferentially to ensure that the force applied to the outer ring of the bearing or the bearing housing is uniform and concentric, avoiding uneven internal stress, decreased rotational accuracy, or abnormal wear of the bearing due to off-center loading.

[0027] The clamping pin penetrates the pressure plate, resulting in a relatively small contact area (compared to direct contact with the entire push rod end face). This reduces frictional resistance during axial movement of the push rod, improving adjustment response speed and accuracy. The holes on the pressure plate guide the clamping pin, helping to maintain the linearity and stability of the push rod's movement.

[0028] Both the outer casing 2 and the push rod 5 are U-shaped, and a gap is left between the first stepped surface of the push rod 5 and the end of the outer casing 2. This gap provides the necessary physical space for the electromagnet to attract the push rod (when it is necessary to reduce the preload). At the same time, the U-shaped structure forms a stepped surface, and the gap between the first stepped surface and the end of the outer casing limits the maximum stroke of the push rod in the direction of the electromagnet. This prevents the spring from being damaged by excessive compression and also prevents the electromagnet from rigidly colliding with the push rod.

[0029] The gap between the energized coil electromagnet 1 and the push rod 5 is greater than the gap between the first stepped surface of the push rod 5 and the end of the housing 2. The push rod 5 also has a second stepped surface in its middle section, and the pressure load sensor 4 is sleeved on the push rod 5 and abuts against the second stepped surface. The second stepped surface provides a reliable axial positioning reference and bearing surface for the pressure sensor. The sensor is firmly abutted against the stepped surface, ensuring its stable position and accurate force measurement direction (axial force) during the axial movement of the push rod.

[0030] The spring force acts directly on the sensor, which then transmits the force to the push rod (through the second stepped surface). The force flow path is clear and without bypass, ensuring that the measured value is the actual force applied to the push rod (and then transmitted to the bearing). At the same time, the sleeve structure combined with the stepped surface limiter effectively prevents the sensor from radially shifting or rotating on the push rod, ensuring measurement stability and accuracy.

[0031] This utility model integrates the control mechanism on the motor end cover, enabling it to sense and compensate for changes in bearing preload caused by temperature rise (thermal expansion), wear, vibration, or changes in operating conditions (such as load and speed changes) in real time. This directly overcomes the fatal defects of traditional passive preload mechanisms, which "cannot dynamically compensate" and "require stopping the machine for disassembly and adjustment." Furthermore, the bearing preload precision control mechanism integrates springs, sensors, and push rods into a sliding structure, resulting in a compact layout and high force transmission efficiency.

[0032] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0033] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention without departing from the principles and spirit of the present invention. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A precise control mechanism for the preload of a motor bearing, characterized in that, The device includes an energized coil electromagnet (1), a housing (2), a spring (3), a pressure load sensor (4), a push rod (5), and a pressure plate (6). The energized coil electromagnet (1) is fixed at one end of the housing (2), and the pressure plate (6) is fixed at the other end of the housing (2). The push rod (5) is slidably disposed inside the housing (2). The pressure load sensor (4) and the spring (3) are sleeved on the push rod (5). One end of the spring (3) abuts against the energized coil electromagnet (1), and the other end abuts against the pressure load sensor (4). Under the action of the spring (3), the end of the push rod (5) protrudes through the pressure plate (6).

2. The precise control mechanism for motor bearing preload according to claim 1, characterized in that, Multiple clamping columns are equidistantly arranged at the end of the push rod (5) along the circumference, and the clamping columns penetrate the pressure plate (6).

3. The precise control mechanism for motor bearing preload according to claim 1, characterized in that, Both the outer shell (2) and the push rod (5) are convex in shape, and there is a gap between the first step surface of the push rod (5) and the end of the outer shell (2).

4. The precise control mechanism for motor bearing preload according to claim 3, characterized in that, The gap between the energized coil electromagnet (1) and the push rod (5) is greater than the gap between the first step surface of the push rod (5) and the end of the outer shell (2).

5. The precise control mechanism for motor bearing preload according to claim 1, characterized in that, The push rod (5) is also provided with a second step surface in the middle. The pressure load sensor (4) is sleeved on the push rod (5) and abuts against the second step surface.

6. An electric motor, comprising a motor housing (100), a stator assembly (200), a rotor core (300), and a shaft (400), wherein motor end caps A (500) and B (600) are respectively fixed to both ends of the motor housing (100), the stator assembly (200) is fixed to the inner wall of the motor housing (100), the rotor core (300) is fixed to the shaft (400), and both ends of the shaft (400) are rotatably connected to the motor end caps A (500) and B (600) respectively via bearings (700); characterized in that: The motor end cover A (500) or the motor end cover B (600) is further fixed with a motor bearing preload precision control mechanism as described in any one of claims 1 to 5, and the push rod (5) presses against the bearing (700).

7. The motor according to claim 6, characterized in that, A positioning protrusion ring is provided on the motor end cover A (500) or motor end cover B (600), and a retaining ring is also provided on the end of the outer shell (2) away from the electromagnet (1) of the energized coil, and the retaining ring is sleeved and fixed on the positioning protrusion ring.

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