Low-vibration canned motor pump rotor

Abstract

The application discloses a low-vibration shielding pump rotor, which comprises a rotor body and an impeller arranged at the front end of the rotor body. The rotor body comprises a main shaft, a first bearing assembly, a rotor assembly and a second bearing assembly which are sequentially arranged on the main shaft. The impeller is arranged at one end of the main shaft close to the first bearing assembly, and the first bearing assembly and the second bearing assembly are respectively provided with a first locking piece and a second locking piece at the ends away from each other. When the rotor body and the impeller rotate together, the first locking piece and the second locking piece are pressed at the two ends of the rotor body. The first locking piece and the second locking piece are arranged to fix the first bearing assembly and the second bearing assembly, so that the relative position change between the first bearing assembly, the second bearing assembly and the main shaft before and after the impeller is disassembled is avoided. In combination with the control of the cooperation gap between the shaft hole of the impeller and the main shaft and the perpendicularity of the left end surface of the first locking piece and the main shaft, the change of the dynamic balance of the low-vibration shielding pump rotor before and after the impeller is disassembled is greatly reduced.

Description

Technical Field

[0001] This invention relates to the field of shielded pump technology, and more particularly to a low-vibration shielded pump rotor. Background Technology

[0002] As the requirements for vibration and noise levels of centrifugal pumps used on ships become increasingly stringent, compared to centrifugal pumps that use mechanical seals and rolling bearings, canned motor pumps, which use sliding bearings and have the entire rotor immersed in the medium being transported, not only avoid high-frequency vibrations generated by rolling bearings, but also allow the medium being transported to absorb some of the high-frequency vibrations. Therefore, they have a clear advantage in terms of high-frequency vibration.

[0003] However, canned motor pumps are at a disadvantage in low-frequency vibration (mainly at 1 times, 1 / 2 times, and 2 times the shaft frequency). The main factor affecting the low-frequency vibration of canned motor pumps is the dynamic balance of the rotor. Conventional canned motor pump rotors have the following deficiencies in dynamic balance:

[0004] 1. The asymmetrical design of the rotor structure results in a large initial dynamic imbalance of the rotor;

[0005] 2. During the hydraulic and vibration commissioning of the canned motor pump, the impeller needs to be repeatedly disassembled and reassembled. Due to the limitations of structure and assembly precision, the rotor of a conventional canned motor pump will have inconsistent dynamic balance before and after disassembly and reassembly.

[0006] 3. After achieving dynamic balance calibration of the dry rotor by adding weight, the rotor structure has severe local bulges. When the canned pump rotor is running, it interacts with the conveying medium, which causes external force interference to the rotor, thereby increasing the wet dynamic imbalance of the rotor, and ultimately leading to large low-frequency vibration of the canned pump.

[0007] 4. Conventional canned pump rotors can only be calibrated under dry conditions and cannot be calibrated under "online dynamic balancing" conditions, meaning they cannot be calibrated under wet conditions.

[0008] Therefore, how to improve the technical defects existing in the prior art has always been a problem that ordinary people skilled in the art need to solve. Summary of the Invention

[0009] The purpose of this invention is to provide a low-vibration canned pump rotor with good dynamic balance, and to ensure the consistency of rotor dynamic balance before and after impeller disassembly and assembly during the commissioning process of the canned pump.

[0010] The technical solution provided by this invention is as follows:

[0011] A low-vibration shielded pump rotor, characterized in that it comprises:

[0012] Rotor body and impeller located at the front end of the rotor body;

[0013] The rotor body includes a main shaft and a first bearing assembly, a rotor assembly, and a second bearing assembly sequentially sleeved on the main shaft.

[0014] The impeller is located at one end of the main shaft near the first bearing assembly, and the first bearing assembly and the second bearing assembly are respectively equipped with a first locking member and a second locking member at their ends that are far apart from each other;

[0015] When the rotor body and the impeller rotate together, the first locking member and the second locking member press against both ends of the rotor body.

[0016] In some embodiments, both the first locking member and the second locking member are nuts; and

[0017] The thread direction of the first locking member is opposite to that of the thread direction of the second locking member, and the main shaft is provided with external threads that cooperate with the first locking member and the second locking member respectively at the locations corresponding to the first locking member and the second locking member.

[0018] In some embodiments, the end of the first locking member away from the first bearing assembly has a machining allowance;

[0019] and / or

[0020] The second locking element is two in number, and is sequentially disposed at the end of the second bearing assembly away from the rotor assembly;

[0021] and / or

[0022] The first locking member is provided with two working holes for applying tightening torque, and the working holes are symmetrically distributed along the central axis of the first locking member.

[0023] In some embodiments, the rotor assembly includes a rotor core, a shielding sleeve fitted onto the rotor core, and a first cover plate and a second cover plate respectively fixed to both ends of the rotor core.

[0024] The first cover plate is disposed at one end of the rotor core facing the first bearing assembly, and has a first boss extending toward the first bearing assembly; the second cover plate is disposed at one end of the rotor core facing the second bearing assembly, and has a second boss extending toward the second bearing assembly; and

[0025] The second boss has a plurality of adjustment holes at one end facing the second bearing assembly, and the plurality of adjustment holes are evenly spaced around the second boss.

[0026] In some embodiments, the first bearing assembly includes a first thrust disk and a first bushing disposed at one end of the first thrust disk away from the rotor assembly, and the second bearing assembly includes a second thrust disk and a second bushing disposed at one end of the second thrust disk away from the rotor assembly.

[0027] The first thrust plate, the first bushing, and the main shaft are provided with a first mounting station for accommodating the key, and the second thrust plate, the second bushing, and the main shaft are provided with a second mounting station for accommodating the key.

[0028] In some embodiments, the first installation station and the second installation station are positioned 180 degrees opposite each other along the central axis of the spindle.

[0029] In some embodiments, both the first bushing and the second bushing are transition-fitted with the main shaft;

[0030] and / or

[0031] Both the first bushing and the second bushing have at least one annular boss on their inner sidewalls.

[0032] In some embodiments, the impeller is fixed to the front end of the main shaft by a locking screw, and the main shaft is provided with a threaded hole that matches the locking screw;

[0033] The impeller and the main shaft are provided together with at least one third mounting station for accommodating the key.

[0034] In some embodiments, the number of the third installation stations is two, and they are symmetrically distributed along the central axis of the main shaft;

[0035] and / or

[0036] The impeller and the main shaft are in clearance fit, and the clearance is no greater than 0.01 mm.

[0037] In some embodiments, the locking screw is an internal hexagonal flathead screw;

[0038] and / or

[0039] An anti-loosening washer is provided between the locking screw and the impeller, and the anti-loosening washer has an axisymmetric structure.

[0040] The technical advantages of this invention are as follows:

[0041] 1. In this patent, by setting a first locking member and a second locking member, the first bearing assembly and the second bearing assembly are fixed, so that the first bearing assembly, the rotor assembly, and the second bearing assembly are in a combined structure. Thus, when the user disassembles or assembles the impeller, the relative position of the first and second bearing assemblies and the main shaft will not change. Combined with controlling the fit clearance between the impeller shaft hole and the main shaft and improving the perpendicularity of the left end face of the first locking member to the main shaft, the change in the dynamic balance of the canned pump rotor before and after impeller disassembly and assembly is greatly reduced. Moreover, the first and second locking members can press against both ends of the rotor body during rotation, preventing them from loosening, resulting in higher structural strength and better stability of the canned pump rotor. Furthermore, the pressing of the first and second locking members against both ends of the rotor body also prevents the first and second bearing assemblies from shifting position during rotation, resulting in a more stable dynamic balance.

[0042] 2. In this patent, by setting a first boss and a second boss, the user can perform dynamic balance calibration by reducing the size of the first boss and the second boss. Compared with the prior art that uses counterweights for dynamic balance calibration, the weight reduction method adopted in this patent effectively reduces the wet dynamic imbalance of the low-vibration shielded pump rotor caused by the added weight. In addition, by setting a second boss and setting evenly spaced adjustment holes on the second boss, the user can perform online dynamic balance adjustment of the low-vibration shielded pump by adding screw counterweights to the adjustment holes, thereby further reducing the low-frequency vibration of the shielded pump.

[0043] 3. In this patent, by setting multiple axisymmetric structures that are 180 degrees opposite each other along the central axis of the main shaft, the initial dynamic imbalance of the canned pump rotor is greatly reduced, and at the same time, the low-frequency hydraulic vibration caused by the internal flow field disturbance of the impeller is eliminated. Attached Figure Description

[0044] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0045] Figure 1 This is a schematic diagram of a common canned motor pump;

[0046] Figure 2 This is a schematic diagram of the rotor structure of a canned motor pump in the prior art;

[0047] Figure 3 This is a schematic diagram of the structure of the low-vibration shielded pump rotor provided by the present invention;

[0048] Figure 4 This is a schematic diagram of the structure of the first bushing provided by the present invention;

[0049] Figure 5 This is a three-dimensional structural schematic diagram of the first locking member provided by the present invention;

[0050] Figure 6 This is a three-dimensional structural schematic diagram of a partial cross-section of the second cover plate provided by the present invention.

[0051] Explanation of icon numbers:

[0052] 100. Rotor body; 110. Main shaft; 120. First bearing assembly; 121. First thrust plate; 122. First bushing; 130. Rotor assembly; 131. Rotor core; 132. Shielding sleeve; 133. First cover plate; 1331. First boss; 134. Second cover plate; 1341. Second boss; 1342. Adjustment hole; 140. Second bearing assembly; 141. Second thrust plate; 142. Second bushing; 150. First locking element; 151. Functional hole; 160. Second locking element; 170. Annular boss;

[0053] 200. Impeller;

[0054] 300, key;

[0055] 400. Locking screws;

[0056] 500. Anti-loosening washers;

[0057] 601. Bearing housing; 602. Adjusting washer; 603. Metal bushing. Detailed Implementation

[0058] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application can also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0059] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings and other implementation methods can be obtained based on these drawings without any creative effort.

[0060] To keep the drawings concise, each figure only schematically shows the parts relevant to the invention, and these do not represent the actual structure of the product. Furthermore, to facilitate understanding, in some figures, only one of components with the same structure or function is schematically depicted, or only one is labeled. In this document, "one" not only means "only one," but can also mean "more than one."

[0061] It should also be further understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0062] In this document, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0063] In the embodiments shown in the accompanying drawings, the directional indications (such as up, down, left, right, front, and back) used to explain the structure and movement of the various components of the invention are relative rather than absolute. These descriptions are appropriate when these components are in the positions shown in the drawings. If the descriptions of the positions of these components change, these directional indications also change accordingly.

[0064] Furthermore, in the description of this application, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0065] According to a specific embodiment provided by the present invention, see [link to specific embodiment]. Figures 1 to 6 A low-vibration shielded pump rotor may specifically include a rotor body 100 and an impeller 200 disposed at the front end of the rotor body 100. The rotor body 100 includes a main shaft 110 and a first bearing assembly 120, a rotor assembly 130, and a second bearing assembly 140 sequentially sleeved on the main shaft 110. The impeller 200 is disposed at the end of the main shaft 110 near the first bearing assembly 120, and a first locking member 150 and a second locking member 160 are respectively installed at the ends of the first bearing assembly 120 and the second bearing assembly 140 that are far apart from each other. When the rotor body 100 and the impeller 200 rotate together, the first locking member 150 and the second locking member 160 press against both ends of the rotor body 100.

[0066] In this embodiment, the first bearing assembly 120 and the second bearing assembly 140 are fixed by setting the first locking member 150 and the second locking member 160, so that the first bearing assembly 120, the rotor assembly 130 and the second bearing assembly 140 are in a combined structure. Thus, when the user disassembles or assembles the impeller 200, the relative positions of the first bearing assembly 120 and the second bearing assembly 140 and the main shaft 110 will not change, keeping the dynamic balance of the rotor body 100 unchanged. Furthermore, the first locking member 150 and the second locking member 160 can press against both ends of the rotor body 100 during rotation, preventing them from loosening, resulting in higher structural strength and better stability of the low-vibration shielded pump rotor. In addition, the pressing of the first locking member 150 and the second locking member 160 against both ends of the rotor body 100 also prevents the first bearing assembly 120 and the second bearing assembly 140 from shifting position during rotation, further stabilizing the dynamic balance.

[0067] Specifically, see Figure 5 Both the first locking member 150 and the second locking member 160 are nuts with cylindrical outer surfaces, and the thread direction of the first locking member 150 is opposite to that of the second locking member 160. At this time, the spindle 110 is provided with external threads corresponding to the first locking member 150 and the second locking member 160, respectively, to cooperate with the first locking member 150 and the second locking member 160.

[0068] Generally, when viewed from the end where the impeller 200 is located, the rotor of the low-vibration shielded pump should rotate counterclockwise during operation, which can be understood as left-handed. In this case, to prevent the first locking member 150 from loosening during rotation, its thread should be right-handed, i.e., a nut with a positive thread should be used. Conversely, if viewed from the end away from the impeller 200, it rotates clockwise, which can also be understood as right-handed. In this case, to prevent the second locking member 160 from loosening during rotation, its thread should be left-handed, i.e., a nut with a reverse thread should be used. Furthermore, this arrangement ensures that the first locking member 150 and the second locking member 160 become increasingly tightened to the rotor body 100 during rotation, thus preventing the first bearing assembly 120 and the second bearing assembly 140 from shifting position during rotation, resulting in a more stable dynamic balance and higher structural strength.

[0069] Of course, in actual production, if the rotor of the low-vibration shielded pump rotates clockwise when viewed from the end where the impeller 200 is located, then the thread orientation of the first locking member 150 should be left-handed, that is, a nut with reverse thread should be used; the thread orientation of the second locking member 160 should be right-handed, that is, a nut with positive thread should be used.

[0070] Specifically, the end of the first locking member 150 away from the first bearing assembly 120 has a machining allowance, which is used to adjust the gap between the impeller 200 and the bearing housing 601 to meet the design requirements.

[0071] In the existing technology, see Figure 1 and Figure 2 One or more adjusting shims 602 are usually placed between the impeller 200 and the first bearing assembly 120 to adjust the gap between the impeller 200 and the bearing housing 601. However, the adjusting shims 602 are mostly very thin and easily deformed. In addition, due to the limitations of the manufacturing precision of individual parts, it is difficult to guarantee the perpendicularity of the end face of the impeller 200 to the main shaft 110 after the impeller 200 is installed. Furthermore, it is impossible to guarantee the consistency of the dynamic balance of the canned pump rotor before and after the impeller 200 is disassembled and assembled, thus affecting the low-frequency vibration of the low-vibration canned pump rotor.

[0072] In this embodiment, the adjusting washer 602 is eliminated. The gap between the impeller 200 and the bearing housing 601 is adjusted by the machining allowance reserved by the first locking member 150. This can greatly improve the perpendicularity between the first locking member 150 and the main shaft 110, thereby ensuring the perpendicularity between the end face of the impeller 200 and the main shaft 110. This effectively reduces the initial dynamic imbalance of the canned pump rotor caused by manufacturing and assembly errors, and also ensures the consistency of dynamic balance before and after impeller disassembly and assembly.

[0073] Specifically, adjusting the clearance between the impeller 200 and the bearing housing 601 by using the machining allowance reserved in the first locking member 150 may include the following steps:

[0074] S1. Determine the machining amount: First, test-assemble the entire shielded pump (excluding the pump body) and measure the gap between the impeller 200 and the corresponding bearing seat 601. The difference between the measured gap and the design gap is the machining amount of the first locking part 150.

[0075] S2. Disassemble the canned pump and remove the rotor body 100;

[0076] S3. Mount the rotor body 100 on the machine tool, clamp the center holes at both ends of the spindle 110, align the center axis, and process the end face of the first locking member 150 into place according to the machining amount determined in S1.

[0077] Furthermore, there are two second locking members 160, which are sequentially located at the end of the second bearing assembly 140 away from the rotor assembly 130. This can further and effectively prevent the positional displacement of the second bearing assembly 140 caused by the second locking member 160 loosening during rotation, and make the dynamic balance state more stable.

[0078] Furthermore, see Figure 5The first locking member 150 is provided with two working holes 151 for applying tightening torque. These working holes 151 are symmetrically distributed along the central axis of the first locking member 150, ensuring that the center of gravity of the entire rotor body 100 falls on the central axis of the main shaft 110, thereby essentially eliminating the initial dynamic imbalance caused by the asymmetry of the component structure. Furthermore, by providing the working holes 151, this embodiment makes it easier for the user to tighten the first locking member 150 onto the first bearing assembly 120, making installation convenient and quick.

[0079] It is worth noting that, apart from the different thread direction, the structure of the second locking member 160 should be similar to that of the first locking member 150. In this regard, the second locking member 160 should also be provided with two working holes 151 for applying tightening torque, and the two working holes 151 should be symmetrically distributed along the central axis of the second locking member 160.

[0080] In actual production, the aforementioned functional hole 151 can be a round hole or a rectangular hole, or it can be replaced with a slot of any shape. There are no restrictions here, and all are within the protection scope of this invention. Of course, if a slot is provided to form the aforementioned functional hole 151, then the slot should be provided on the side of the first locking member 150 and the second locking member 160 that are far apart from each other.

[0081] Specifically, see Figure 3 and Figure 6 The rotor assembly 130 includes a rotor core 131, a shielding sleeve 132 fitted onto the rotor core 131, and a first cover plate 133 and a second cover plate 134 respectively fixed to both ends of the rotor core 131. The first cover plate 133 is located at the end of the rotor core 131 facing the first bearing assembly 120, and extends towards the first bearing assembly 120 with a first boss 1331. Conversely, the second cover plate 134 is located at the end of the rotor core 131 facing the second bearing assembly 140, and extends towards the second bearing assembly 140 with a second boss 1341. The end of the second boss 1341 facing the second bearing assembly 140 has a plurality of adjustment holes 1342, which are evenly spaced around the second boss 1341.

[0082] In this embodiment, see Figure 2 and Figure 3 By setting a first boss 1331 and a second boss 1341, the user can perform dynamic balance calibration by reducing the weight of the first boss 1331 and the second boss 1341. Compared with the prior art of performing dynamic balance calibration by adding counterweights, the weight reduction method adopted in this patent effectively reduces the wet dynamic imbalance of the low-vibration shielded pump rotor caused by the added weight. Where operating space permits, the weight reduction method using the end faces of the first boss 1331 and the second boss 1341 is preferred for dynamic balance calibration.

[0083] In addition, see Figure 6 In this patent, by setting evenly spaced adjustment holes 1342 on the second protrusion 1341, the user can perform online dynamic balancing of the low-vibration shielded pump by adding screw counterweights to the adjustment holes 1342, thereby further reducing the low-frequency vibration of the low-vibration screen. The more adjustment holes 1342 there are, the higher the adjustment accuracy of the online dynamic balancing; therefore, the number of adjustment holes 1342 is generally no less than 8.

[0084] Specifically, the online dynamic balancing of the low-vibration shielded pump is achieved by adding a screw counterweight to the adjustment hole 1342, which may include the following steps:

[0085] S1. Number and mark the multiple debugging holes 1342 of the second cover plate 134, and screw the same screw into the debugging holes 1342 with different numbers in sequence, and test the shaft frequency vibration of the shielded pump of the whole machine.

[0086] S2. Determine the number of the adjustment hole 1342 corresponding to the minimum shaft frequency vibration based on the test results, and record it.

[0087] S3. Screw screws of different lengths into the debugging hole 1342 and test the shaft frequency vibration of the shielded pump on the whole machine.

[0088] S4. Based on the whole machine shaft frequency vibration test results, determine the screw length corresponding to the minimum shaft frequency vibration, screw the screw into the recorded debugging hole 1342, and the debugging is completed.

[0089] Specifically, see Figure 3 The first bearing assembly 120 includes a first thrust plate 121 and a first bushing 122 disposed at the end of the first thrust plate 121 away from the rotor assembly 130, and the second bearing assembly 140 includes a second thrust plate 141 and a second bushing 142 disposed at the end of the second thrust plate 141 away from the rotor assembly 130. It is worth noting that the first thrust plate 121, the first bushing 122 and the main shaft 110 are jointly provided with a first mounting position for accommodating the key 300, and the second thrust plate 141, the second bushing 142 and the main shaft 110 are jointly provided with a second mounting position for accommodating the key 300.

[0090] In this embodiment, by installing keys 300 in the first and second installation positions, the first bearing assembly 120 and the second bearing assembly 140 can rotate synchronously with the main shaft 110, thus ensuring the structural stability of the low-vibration shielded pump rotor during operation.

[0091] Specifically, the first thrust plate 121 and the first bushing 122 are provided with a first slot and a second slot, which are connected to form a first groove. At this time, the main shaft 110 is provided with a second groove corresponding to the first groove, and the first and second grooves together form a first mounting position for placing the key 300. Conversely, the second thrust plate 141 and the second bushing 142 are provided with a third slot and a fourth slot, which are connected to form a third groove. At this time, the main shaft 110 is provided with a fourth groove corresponding to the third groove, and the third and fourth grooves together form a second mounting position for placing the key 300.

[0092] It is worth noting that, see Figure 3 Except for the first and third slots, the first thrust plate 121 and the second thrust plate 141 should both be axisymmetric. Similarly, except for the second and fourth slots, the first bushing 122 and the second bushing 142 should both be axisymmetric.

[0093] Preferably, see Figure 2 and Figure 3 The first and second mounting stations are positioned 180 degrees apart along the central axis of the main shaft 110. In the prior art, the various components of a commonly used low-vibration shielded pump rotor are connected by a single key 300. Furthermore, for ease of processing, the mounting stations for placing the key 300 are generally located in the same direction. This can easily lead to a large initial dynamic imbalance in the low-vibration shielded pump rotor due to the asymmetry of the component structure. In this embodiment, however, the first and second mounting stations are positioned 180 degrees apart along the central axis of the main shaft 110, ensuring that the center of gravity of the entire rotor body 100 falls on the axis of the rotor body 100, thereby effectively eliminating the initial dynamic imbalance caused by structural asymmetry in the prior art.

[0094] Furthermore, in the prior art, metal bushings 603 are also provided between the first bushing 122 and the main shaft 110, and between the second bushing 142 and the main shaft 110. However, because the first bushing 122 and the second bushing 142 commonly used in the prior art are generally made of silicon carbide or graphite, and their coefficients of thermal expansion are different from those of the metal bushing 603, a clearance fit must be used between the first bushing 122 and the metal bushing 603, and between the second bushing 142 and the metal bushing 603, to prevent damage to the parts due to the different degrees of thermal expansion when the temperature rises. However, this arrangement affects the coaxiality between the first bushing 122 and the main shaft 110, and between the second bushing 142 and the main shaft 110 to some extent, resulting in an initial dynamic imbalance.

[0095] In this embodiment, both the first bushing 122 and the second bushing 142 are made of metal, eliminating the need for an additional metal bushing 603. This effectively reduces the coaxiality deviation between the bushing and the shaft assembly. Furthermore, by eliminating the metal bushing 603, the outer diameters of the first bushing 122 and the second bushing 142 can be reduced. Consequently, at the same rotational speed, the linear velocity of the outer surfaces of the first bushing 122 and the second bushing 142 will be correspondingly lower, thereby reducing wear and increasing their service life.

[0096] Specifically, the outer surfaces of the first bushing 122 and the second bushing 142 are both cylindrical, and both ends of the outer surfaces of the first bushing 122 and the second bushing 142 are edged, with tungsten carbide or other wear-resistant coatings thermally sprayed in the middle of the edged surface.

[0097] At this time, the first bushing 122 and the main shaft 110, and the second bushing 142 and the main shaft 110 can be in transition fit. Under the condition that the first bushing 122 and the second bushing 142 can be disassembled and replaced, the coaxiality between the first bushing 122 and the main shaft 110, and the second bushing 142 and the main shaft 110 is further improved, thereby effectively reducing the initial dynamic imbalance of the rotor.

[0098] Furthermore, see Figure 4 The inner sidewalls of the first bushing 122 and the second bushing 142 are each provided with at least one annular boss 170, so that the first bushing 122 and the second bushing 142 can better adapt to the thermal expansion and contraction of the first bushing 122, the second bushing 142 and the main shaft 110. While avoiding damage to the parts, the coaxiality between the first bushing 122 and the main shaft 110, and between the second bushing 142 and the main shaft 110 is guaranteed. The structure is reasonably designed and highly practical.

[0099] In one specific embodiment, see Figure 3 The impeller 200 is fixed to the front end of the main shaft 110 by a locking screw 400, the thread direction of which should be consistent with the thread direction of the first locking member 150. At this time, the main shaft 110 is provided with a threaded hole adapted to the locking screw 400. The impeller 200 and the main shaft 110 together have at least one third mounting station for accommodating the key 300.

[0100] In this embodiment, by installing a key 300 in the third installation station, the impeller 200 and the main shaft 110 can rotate synchronously, ensuring the structural stability of the low-vibration shielded pump rotor during operation.

[0101] Preferably, see Figure 2 and Figure 3The third installation station has two units, which are symmetrically distributed along the central axis of the main shaft 110. In the prior art, the various components of the commonly used low-vibration shielded pump rotor are connected by a single key 300. However, in this embodiment, the impeller 200 and the main shaft 110 are connected by a symmetrical double key 300, so that the center of gravity of the impeller 200 can fall on the central axis of the main shaft 110, thereby effectively eliminating the initial dynamic imbalance caused by structural asymmetry in the prior art.

[0102] Of course, in actual production, the number of third installation stations can be three or four, or even more, as long as they are evenly spaced around the main shaft 110. These will not be elaborated here, as they are all within the protection scope of this invention.

[0103] Specifically, in all the above embodiments, the key 300 and the corresponding installation station are connected normally, which is different from the loose connection used in the low vibration shielded pump rotor commonly used in the prior art. Under the premise of ensuring disassembly and assembly, it can effectively avoid the change of orientation angle between the key 300 and the main shaft 110 during disassembly and assembly, thereby ensuring the consistency of dynamic balance of the low vibration shielded pump rotor provided by this patent before and after disassembly and assembly.

[0104] Furthermore, the impeller 200 and the main shaft 110 are clearance fit, and the clearance is no more than 0.01mm. This ensures the coaxiality of the impeller 200 and the main shaft 110 while also meeting the need for frequent disassembly and assembly of the impeller 200.

[0105] The locking screw 400 is a hexagonal flat-head screw, and an anti-loosening washer 500 with an axisymmetric structure, such as a DIN25201 double-layer self-locking washer, is provided between the locking screw 400 and the impeller 200. In this embodiment, by providing the anti-loosening washer 500, the locking screw 400 can be prevented from loosening during rotation, ensuring the stable operation of the low-vibration shielded pump rotor. Furthermore, the axisymmetric structure of both the locking screw 400 and the anti-loosening washer 500 ensures that the center of gravity of the entire low-vibration shielded pump rotor is located on the central axis of the main shaft 110, eliminating the large initial dynamic imbalance caused by the asymmetry of the component structure. On the other hand, it prevents periodic disturbances in the internal flow field of the impeller 200 due to the asymmetric structure, thereby eliminating the low-frequency hydraulic vibration of the low-vibration shielded pump rotor caused by the internal flow field disturbances of the impeller 200.

[0106] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0107] It should be noted that the above embodiments can be freely combined as needed. The above are merely preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A low-vibration shielded pump rotor, characterized in that, include: Rotor body and impeller located at the front end of the rotor body; The rotor body includes a main shaft and a first bearing assembly, a rotor assembly, and a second bearing assembly sequentially sleeved on the main shaft. The impeller is located at the end of the main shaft near the first bearing assembly. The ends of the first and second bearing assemblies that are far apart from each other are respectively equipped with a first locking element and a second locking element. By setting the first and second locking elements, the first and second bearing assemblies are fixed, resulting in a combined structure of the first bearing assembly, the rotor assembly, and the second bearing assembly. When the impeller is disassembled, the relative positions of the first and second bearing assemblies and the main shaft do not change, and the dynamic balance of the rotor body remains unchanged. A machining allowance is left at the end of the first locking element far from the first bearing assembly. The rotor body is fitted with a bearing housing. The measured clearance between the impeller and the bearing housing differs from the designed clearance. The machining allowance is configured to machine this difference to adjust the clearance between the impeller and the bearing housing and ensure the perpendicularity of the impeller end face to the main shaft, thereby reducing the initial dynamic imbalance of the canned pump rotor and ensuring the consistency of the dynamic balance before and after impeller disassembly and assembly. When the rotor body and the impeller rotate together, the first locking member and the second locking member press against both ends of the rotor body; The rotor assembly includes a rotor core, a shielding sleeve fitted onto the rotor core, and a first cover plate and a second cover plate respectively fixed to both ends of the rotor core. The first cover plate is disposed at one end of the rotor core facing the first bearing assembly, and has a first boss extending toward the first bearing assembly; the second cover plate is disposed at one end of the rotor core facing the second bearing assembly, and has a second boss extending toward the second bearing assembly; and The second boss has a plurality of adjustment holes at one end facing the second bearing assembly, and the plurality of adjustment holes are evenly spaced around the second boss.

2. The low-vibration shielded pump rotor according to claim 1, characterized in that... , Both the first locking element and the second locking element are nuts; and The thread direction of the first locking member is opposite to that of the thread direction of the second locking member, and the main shaft is provided with external threads that cooperate with the first locking member and the second locking member respectively at the locations corresponding to the first locking member and the second locking member.

3. The low-vibration shielded pump rotor according to claim 1 or 2, characterized in that, The second locking element is two in number, and is sequentially disposed at the end of the second bearing assembly away from the rotor assembly; and / or The first locking member is provided with two working holes for applying tightening torque, and the working holes are symmetrically distributed along the central axis of the first locking member.

4. The low-vibration shielded pump rotor according to claim 1 or 2, characterized in that, The first bearing assembly includes a first thrust disk and a first bushing disposed at one end of the first thrust disk away from the rotor assembly, and the second bearing assembly includes a second thrust disk and a second bushing disposed at one end of the second thrust disk away from the rotor assembly; The first thrust plate, the first bushing, and the main shaft are provided with a first mounting station for accommodating the key, and the second thrust plate, the second bushing, and the main shaft are provided with a second mounting station for accommodating the key.

5. The low-vibration shielded pump rotor according to claim 4, characterized in that, The first installation station and the second installation station are positioned 180 degrees apart along the central axis of the main shaft.

6. The low-vibration shielded pump rotor according to claim 4, characterized in that, Both the first bushing and the second bushing have an transition fit with the main shaft; and / or Both the first bushing and the second bushing have at least one annular boss on their inner sidewalls.

7. The low-vibration shielded pump rotor according to claim 1 or 2, characterized in that, The impeller is fixed to the front end of the main shaft by a locking screw, and the main shaft is provided with a threaded hole that matches the locking screw; The impeller and the main shaft are provided together with at least one third mounting station for accommodating the key.

8. The low-vibration shielded pump rotor according to claim 7, characterized in that, The number of the third installation stations is two, and they are symmetrically distributed along the central axis of the main shaft; and / or The impeller and the main shaft are in clearance fit, and the clearance is no greater than 0.01 mm.

9. The low-vibration shielded pump rotor according to claim 7, characterized in that, The locking screw is an internal hexagonal flat head screw; and / or An anti-loosening washer is provided between the locking screw and the impeller, and the anti-loosening washer has an axisymmetric structure.

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