Automatically centering and axially displaceable motor and mounting structure for a motor and a reduction gearbox

Abstract

An automatically centering and axially displaceable motor comprising a housing, a stator (2) and a rotor (3), wherein the stator (2) is fixed in the housing, the rotor (3) is arranged in the stator (2), and the rotor (3) is rotatably connected to the housing via a bearing A (30), characterized in that a centering soft sleeve (31) is also provided between the bearing A (30) and the housing, wherein the rotor (3) is further provided with a conical sleeve (4) for drive connection with a reduction gear input shaft (5), wherein the conical sleeve (4) is in clearance fit with the rotor (3) and / or the reduction gear input shaft (5) and is driven by means of a keyway structure.

Description

TECHNICAL AREA

[0001] The present utility model belongs to the field of oil pumping technology and relates in particular to an automatically centering and axially displaceable motor with multiple bearings and overpositioning. STATE OF THE ART

[0002] Currently, the retrofitting of pitching machines with semi-direct drives is becoming widespread. In this process, a flat permanent magnet motor is mounted directly onto the input shaft of the reduction gearbox. There are two common types of motors: one is equipped with bearings that allow for easy, safe, and quick assembly and disassembly; the other has no bearing between the stator and the rotor. The stator and rotor are supplied separately, and during on-site assembly, the motor stator is attached to the outer end face of the input bearing chamber of the reduction gearbox, while the motor rotor is mounted separately on the input shaft of the reduction gearbox.

[0003] There are two common designs for semi-direct drives, each with its own advantages and disadvantages. The first design uses a motor with bearings, which simplifies on-site installation. The large overlap of the motor's stator and rotor prevents power loss due to rotor movement caused by the input shaft movement of the reduction gearbox. Furthermore, collisions between the motor rotor and other components are avoided. However, due to the over-positioning between the motor bearing and the two bearings on the reduction gearbox's input shaft, and because the gearbox bearing is much larger than the motor bearing, the motor bearing can be damaged after only a short operating time, which can disrupt production or even cause the motor to burn out.

[0004] While the second solution eliminates the bearing and thus avoids problems caused by excessive bearing over-positioning, it introduces other issues. For example, the separate design of the motor's stator and rotor can lead to damage to motor components during motor production testing, as well as during on-site installation and disassembly. In other words, because the motor rotor contains magnets, metal particles can easily enter the rotor during assembly and disassembly, damaging the motor. Furthermore, when the input shaft of the reduction gearbox moves, the motor rotor also moves synchronously. This can easily lead to interference between the motor rotor and other parts, and can reduce the overlap between the motor rotor and stator, thereby impairing the motor's performance and effectively reducing its power output.If the motor is operated in a field with a high load, it will be overloaded for an extended period of time, which can reduce the motor's lifespan or even cause the motor stator to burn out. CONTENTS OF THE PRESENT USE SAMPLE

[0005] To solve the aforementioned technical problems, the first objective of this utility model is to provide an automatically centering and axially displaceable motor, characterized by a stable structure, good performance and a long service life; the second objective of this utility model is to provide a mounting structure for a motor and a reduction gearbox.

[0006] To achieve the first objective of the aforementioned utility model, the following technical solution is applied in the present utility model: An automatically centering and axially displaceable motor comprising a housing, a stator and a rotor, wherein the stator is fixed in the housing, the rotor is arranged in the stator, and the rotor and the housing are rotatably connected to each other via bearing A, a centering soft sleeve is also provided between bearing A and the housing, wherein the rotor is furthermore provided with a conical sleeve for drive connection to a reduction gear input shaft, wherein the conical sleeve is in clearance fit with the rotor and / or the reduction gear input shaft and is driven by means of a keyway structure.

[0007] As a preferred solution: the housing comprises a housing shell and an end cap which are attached to one another, wherein the end cap is provided internally with a bearing chamber, the bearing A is embedded in the bearing chamber, and a limiting cover plate A is attached to the end face of the bearing chamber, wherein the end face of the rotor is provided with a limiting cover plate B, wherein the limiting cover plate A and the limiting cover plate B each lie at the two ends of the bearing A, so that the bearing A cannot move axially.

[0008] One preferred solution is that the conical sleeve is provided with a conical hole on the inside, the reduction gear input shaft is inserted into the conical hole and is in a press fit with the conical sleeve in terms of drive.

[0009] As a preferred solution: the conical sleeve is provided internally with a conical hole, wherein the conical hole is also provided on its side wall with an internal keyway, the reduction gear input shaft is inserted into the conical hole and is provided with a splined toothing A, wherein the reduction gear input shaft and the conical sleeve transmit force via the interaction of the splined toothing A and the internal keyway.

[0010] As a preferred solution: the conical sleeve is cylindrical as a whole, and the outside of the conical sleeve is also provided with an external keyway, the conical sleeve is embedded in the rotor, the rotor is also provided with a splined toothing B, wherein the rotor and the conical sleeve transmit force through the interaction of the external keyway and the splined toothing B.

[0011] One preferred solution is that the thickness of the centering soft sleeve is less than the gap between the stator and the rotor.

[0012] As a preferred solution: the rotor is provided on at least one of its two axial sides with a protruding ring, wherein the housing is provided with a position sensor that measures the change in position of the protruding ring during rotation.

[0013] As a preferred solution: several position sensors are provided, and the centers of the several position sensors coincide with the center of the circle A of the stator.

[0014] One preferred solution is a flat disk encoder attached to the housing, with the rotor being fitted with an encoder disk that interacts with the flat disk encoder.

[0015] To achieve the second objective of the aforementioned utility model, the following technical solution is applied in the present utility model: Mounting structure for a motor and a reduction gearbox, comprising the motor and gearbox mounted on a mounting frame, the reduction gearbox input shaft is rotatably connected to the mounting frame via bearing B, the motor is an automatically centering and axially displaceable motor according to one of the above points.

[0016] Compared to the prior art, the present utility model has the following advantageous effects: A bearing is arranged between the motor rotor and the housing of the present utility model, which makes the production of the motor and on-site assembly quick and easy. At the same time, a centering soft sleeve is provided between the rotor and the housing. In the event of overpositioning of the reduction gear bearings and motor bearings, the centering soft sleeve undergoes compression deformation to ensure that the motor rotor and the input shaft of the reduction gear form a stable and highly precise coaxial alignment. This protects the motor bearings from loads and significantly extends the service life of the motor. This ensures that the motor bearings function under normal loads and that their service life meets the actual usage requirements with regular maintenance.

[0017] The conical sleeve of the present utility model is in a clearance fit with the rotor and / or the reduction gear input shaft, thereby allowing axial movement between the reduction gear input shaft and the rotor without this axial movement causing axial movement of the motor rotor, thus protecting the motor rotor from collisions with other parts and preventing axial misalignment of the stator and the rotor, which leads to a deterioration of the motor performance. BRIEF DESCRIPTION OF THE DRAWING

[0018] The attached drawings, which form part of this application, serve to provide a better understanding of the present application; the exemplary embodiments and their descriptions serve to explain the present application and do not constitute a limitation of the present application. Fig. Figure 1 is a schematic structural cross-sectional view of the present utility model; Fig. Figure 2 is a schematic structural representation of the conical sleeve of the present utility model. DETAILED DESCRIPTION

[0019] The present utility model is explained in more detail below in conjunction with the attached drawings and examples of embodiments: As in Fig. 1 and Fig.Figure 2 shows an automatically centering and axially displaceable motor with multiple bearings and overpositioning comprising a housing, a stator 2 and a rotor 3, wherein the stator 2 is fixed in the housing, the rotor 3 is arranged in the stator 2, and the rotor 3 is rotatably connected to the housing via the bearing A30, wherein the housing comprises a housing shell 11 and an end cap 12 which are attached to one another, wherein the end cap 12 is provided internally with a bearing chamber, wherein the bearing A30 is embedded in the bearing chamber, and a limiting cover plate A121 is attached to the end face of the bearing chamber, wherein the end face of the rotor 3 is provided with a limiting cover plate B122, wherein the limiting cover plate A121 and the limiting cover plate B122 each lie at the two ends of the bearing A30, so that the bearing A30 cannot move axially.

[0020] The motor is equipped with bearings; the limiting cover plate, the screw limiting bearing, and the motor rotor limit the axial movement of the motor stator and rotor, thus preventing the rotor from moving within the bearing in the motor. This significantly simplifies motor production and testing, as well as on-site installation, and also protects the motor from damage caused by friction and impacts during transport due to the lack of bearings on the rotor or stator.

[0021] Since the motor of the present utility model is mounted with bearings, which, together with the bearing of the reduction gear, can lead to overpositioning of the bearings due to manufacturing and assembly errors, inevitably results in the less resistant bearings being quickly damaged after a certain operating time and thus significantly impairing the operation of the system, a centering soft sleeve 31 is also provided between the bearing A30 of the motor and the housing, wherein the centering soft sleeve 31 is placed on the outer ring of the bearing A30, and the outer wall and the inner wall of the bearing chamber are connected to each other by a press fit, the centering soft sleeve 31 consists of a relatively soft metal ring made of aluminum or copper or the like, the thickness of the centering soft sleeve 31 is less than the gap X between the stator 2 and the rotor 3, and X is typically 2 mm.

[0022] The material and thickness of the centering soft sleeve 31 were precisely designed and tested to determine their specifications. This ensures that, after installation and commissioning of the motor, the centering soft sleeve 31 is pressed against the reduction gear input shaft even if it is overpositioned due to a significantly larger type of reduction gear bearing compared to the motor bearing. This results in a stable and highly precise coaxial alignment between the motor rotor and the reduction gear input shaft. This protects the motor bearings from stress and significantly extends the service life of the motor. It also ensures that the motor bearings function under normal loads and that their service life, with regular maintenance, meets actual usage requirements.

[0023] The rotor 3 is also provided with a conical sleeve 4 for drive connection with a reduction gear input shaft 5, wherein the conical sleeve 4 is in clearance fit with the rotor 3 and / or the reduction gear input shaft 5 and is driven by means of a keyway structure.

[0024] The conical sleeve 4 is provided internally with a conical hole 41, wherein the reduction gear input shaft 5 is inserted into the conical hole 41 and is in a drive-side interference fit with the conical sleeve 4. To further ensure the stability of the power transmission, an additional internal keyway 42 is provided on the side wall of the conical hole 41, wherein the reduction gear input shaft 5 is inserted into the conical hole 41 and the reduction gear input shaft 5 is provided with a splined section A, wherein the reduction gear input shaft 5 and the conical sleeve 4 transmit power via the interaction of the splined section A and the internal keyway 42.

[0025] The conical sleeve 4 is cylindrical as a whole, and the outside of the conical sleeve 4 is also provided with an external keyway 43, wherein the conical sleeve 4 is embedded in the rotor 3, the rotor 3 is also provided with a splined shaft B, the rotor 3 and the conical sleeve 4 are driven by the interaction of the external keyway 43 and the splined shaft B, and an adapting gap 40 is formed between the conical sleeve 4 and the inner hole of the motor rotor.

[0026] The motor rotor of the present utility model is mounted to the reduction gear input shaft via a conical sleeve; the inner hole of the conical sleeve is a conical bore that matches the dimensions of the original reduction gear input shaft; the outer ring is designed as a straight shaft and lies in clearance fitting with the inner bore of the motor rotor and is axially displaceable within the inner bore of the motor rotor; the conical sleeve is provided with an axially penetrating notch that serves to clamp and fix the motor shaft and the reduction gear input shaft.The straight outer shaft of the inner conical bore of the conical sleeve allows for effective attachment to the reduction gear input shaft and ensures that the axial dimensions of the motor rotor are not affected when the reduction gear input shaft moves, therefore the motor can operate safely, stably and with high performance even if the input shaft of the reduction gear moves irregularly during operation on site.

[0027] A flat disk encoder 82 (encoder chip) is attached to the housing, and the flat disk encoder 82 is attached to the limiting cover plate A121, with the rotor 3 being equipped with an encoder disk 81 that interacts with the flat disk encoder 82. Since the motor is mounted on bearings, it can be ensured that no axial movement occurs after the rotor is installed with the stator, thus guaranteeing effective detection by the encoder. The motor is internally mounted with an encoder that allows the motor to be held at "0" speed. This can be used for aligning the support cable during on-site installation and for calibrating measuring instruments in the event of a pipeline leak.

[0028] The rotor 3 of the motor of the present utility model is provided on at least one of its two axial sides with a projecting ring 32, the housing being provided with a position sensor 7 which measures the change in position of the projecting ring 32 during rotation. There are at least three position sensors 7, and the centers of the three position sensors 7 coincide with the center of the circle A of the stator 2.

[0029] On one side of the housing is a control box 6, which houses a controller. The flat disk encoder 82 and the position sensor 7 are connected to the controller via encoder line 61 and position sensor line 62, respectively. The controller calculates the center of rotation B of the rotor 3 based on information acquired by several position sensors 7. If the position difference between the center of rotation B and the center of rotation A is greater than or equal to the distance between the stator 2 and the rotor 3, the controller stops the motor and generates an alarm. This allows the user to immediately identify and rectify the problem, effectively protecting the motor from damage. The aforementioned controller uses the position sensor to calculate the rotor eccentricity and the encoder to control the motor in a closed-loop system. Both of these are existing motor control technologies and will not be discussed in detail here.

[0030] Mounting structure for a motor and a reduction gear, comprising the motor and the gearbox mounted on a mounting frame 9, the reduction gear input shaft 5 is rotatably connected to the mounting frame 9 via bearing B51, the motor is an automatically centering and axially displaceable motor with multiple bearings and overpositioning according to one of the above points.

[0031] As used herein, reference to the descriptions of the terms “an embodiment”, “some embodiments”, “example”, “specific examples”, or “some examples”, or similar terms, means that specific features, structures, materials, or special characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present utility model. In this description, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the described specific features, structures, materials, or special characteristics may be combined in any or more embodiments or examples in any suitable manner.

[0032] Although the embodiments of the present utility model have been shown and described above, it is understood that the above embodiments are exemplary and should not be interpreted as limiting the present utility model. An average person skilled in the art in this field may, within the scope of the present utility model, make changes, modifications, replacements and variations of the embodiments described above without deviating from the principles and spirit of the present utility model. Even simple modifications, equivalent changes and variations of the embodiments described above, which are based on the technical essence of the present utility model, fall within the scope of protection of the technical solution of the present utility model.

Claims

[1] Automatically centering and axially displaceable motor comprising a housing, a stator (2) and a rotor (3), wherein the stator (2) is fixed in the housing, the rotor (3) is arranged in the stator (2) and the rotor (3) is rotatably connected to the housing via a bearing A (30), characterized by , that a centering soft sleeve (31) is also provided between the bearing A (30) and the housing, wherein the rotor (3) is also provided with a conical sleeve (4) for drive connection with a reduction gear input shaft (5), wherein the conical sleeve (4) is in clearance fit with the rotor (3) and / or the reduction gear input shaft (5) and is driven by means of a keyway structure. [2] Automatically centering and axially displaceable motor according to claim 1, characterized by, that the housing comprises a housing shell (11) and an end cap (12) which are attached to each other, wherein the end cap (12) is provided internally with a bearing chamber, the bearing A (30) is embedded in the bearing chamber, and a limiting cover plate A (121) is attached to the end face of the bearing chamber, wherein the end face of the rotor (3) is provided with a limiting cover plate B (122), wherein the limiting cover plate A (121) and the limiting cover plate B (122) each lie at the two ends of the bearing A (30) so that the bearing A (30) cannot move axially. [3] Automatically centering and axially displaceable motor according to claim 1, characterized by , that the conical sleeve (4) is provided internally with a conical hole (41), wherein the reduction gear input shaft (5) is inserted into the conical hole (41) and is in press fit with the conical sleeve (4) in terms of drive. [4] Automatically centering and axially displaceable motor according to claim 1, characterized by , that the conical sleeve (4) is provided internally with a conical hole (41), wherein the conical hole (41) is also provided on its side wall with an internal keyway (42), wherein the reduction gear input shaft (5) is inserted into the conical hole (41) and the reduction gear input shaft (5) is provided with a splined connection A, wherein the reduction gear input shaft (5) and the conical sleeve (4) transmit force via the interaction of the splined connection A and the internal keyway (42). [5] Automatically centering and axially displaceable motor according to claim 1, characterized by, that the conical sleeve (4) as a whole is cylindrical, and the outside of the conical sleeve (4) is also provided with an external keyway (43), wherein the conical sleeve (4) is embedded in the rotor (3), the rotor (3) is also provided with a splined toothing B, wherein the rotor (3) and the conical sleeve (4) transmit force through the interaction of the external keyway (43) and the splined toothing B. [6] Automatically centering and axially displaceable motor according to claim 1, characterized by , that the thickness of the centering soft sleeve (31) is less than the gap between the stator (2) and the rotor (3). [7] Automatically centering and axially displaceable motor according to claim 1, characterized by , that the rotor (3) is provided on at least one of its two axial sides with a protruding ring (32), wherein the housing is provided with a position sensor (7) which measures the change in position of the protruding ring (32) during rotation. [8] Automatically centering and axially displaceable motor according to claim 6, characterized by , that several position sensors (7) are provided, and the centers of the several position sensors (7) coincide with the center of the circle A of the stator (2). [9] Automatically centering and axially displaceable motor according to claim 1, characterized by , that a flat disk encoder (82) is attached to the housing, wherein the rotor (3) is provided with an encoder disk (81) which interacts with the flat disk encoder (82). [10] Mounting structure for a motor and a reduction gear, comprising the motor and the gear which are mounted on a mounting frame (9), wherein the reduction gear input shaft (5) is rotatably connected to the mounting frame (9) via the bearing B (51), characterized by that the motor is an automatically centering and axially displaceable motor according to one of claims 1 to 9.

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