Crankshaft fixing structure and external rotor motor thereof

Abstract

The utility model provides a crankshaft fixing structure and an external rotor motor thereof. The crankshaft fixing structure comprises an impeller, a crankshaft, a fixing support, a left bearing and a right bearing. The outer ring of the left bearing is matched with the fixing support, the inner ring of the left bearing is matched with the crankshaft, the impeller is extended to form an extension end, the extension end abuts against the positioning check ring, and limiting is provided for axial positioning of the positioning check ring from the left side. And the outer ring of the right bearing is matched with the fixed bracket, and the inner ring is matched with the crankshaft. The crankshaft fixing structure provided by the utility model is reasonable in structural design, the positions of the inner rings of the left bearing and the right bearing in the axial direction can be effectively realized through left-right matching, meanwhile, the fixed bracket and the crankshaft are accurately positioned in the axial direction and are stably and well matched, and the fixed bracket, the crankshaft and the outer rotor can normally operate without interference. The external rotor motor using the shaft fixing structure is more stable and reliable in operation, and can be applied to occasions such as axial flow fans and fans.

Description

TECHNICAL FIELD

[0001] The utility model relates to motor technical field especially relates to a machine shaft fixing mechanism and its outer rotor motor. BACKGROUND

[0002] The stator of the outer rotor motor is fixed at the center position of the motor, and the rotor is located at the periphery of the stator and rotates around the stator. Different from the inner rotor motor, the internal stator of the outer rotor motor is static, and the external shell rotates. The outer rotor motor is usually used in impeller design and has the effect of heat dissipation and cooling. The outer rotor motor is also widely used in the field of fans and other fields due to its compact structure, light weight, high efficiency, low noise and other characteristics. When the outer rotor motor is used to produce a fan, the impeller of the fan is usually integrated at the end of the machine shaft or fixed on the outer periphery of the outer rotor.

[0003] The existing outer rotor motor has high requirements for the assembly and installation of each part of the motor. If there is a large error in the assembly and installation or the installation is poor, the fan produced by using the outer rotor motor may have poor stability during operation.

[0004] When the impeller of the fan is fixed at the end of the machine shaft, the impeller and the end of the machine shaft are usually locked and fixed by bolts. In the existing outer rotor motor, the machine shaft is usually axially positioned by a bearing and a fixed support during positioning and assembly. The inner ring of the bearing is usually matched with the outer wall of the machine shaft, and the outer ring of the bearing is matched with the fixed support. When the rotor and the machine shaft rotate, the fixed support does not interfere with the rotation of the rotor and the machine shaft. The rotation of the outer rotor relative to the inner stator drives the rotation of the machine shaft, thereby driving the synchronous rotation of the impeller.

[0005] In this structure, how to complete the axial positioning of the bearing on the basis of the existing structure becomes the key to the positioning and assembly of the machine shaft. The existing positioning method is to design a groove at the position of the machine shaft outside the inner ring of the bearing, and a retainer ring is matched in the groove to position the bearing. In the case of insufficient running stability, the retainer ring is easy to come out of the groove, thereby causing poor positioning of the machine shaft at the position, movement between the machine shaft and the fixed support, and affecting the normal and stable operation of the motor. UTILITY MODEL CONTENTS

[0006] The technical problem to be solved by the utility model is that in order to overcome the shortcomings of the prior art, the utility model provides a machine shaft fixing structure and an outer rotor motor thereof, which overcomes the poor positioning of the machine shaft caused by the simple retainer ring positioning, uses the installation of the impeller and the machine shaft to provide a pressing force in the lateral direction for the positioning retainer ring at one end of the machine shaft, cooperates with the welding positioning at the other end, uses the bearing, can effectively position the machine shaft and the fixed support in the axial direction, and can make the fixed support rotate without interference relative to the machine shaft.

[0007] The utility model discloses a technical scheme that solves its technical problem is adopted: a machine shaft fixing structure, including impeller, machine shaft and fixed bolster, the fixed bolster on be equipped with inner stator, and the outer rotor of inner stator is equipped with relative to the rotation of inner stator, the impeller setting is in the left side end of machine shaft, and this machine shaft fixing structure includes left bearing and right bearing, the outer ring of left bearing is cooperated with fixed bolster, and the inner ring is cooperated with machine shaft, the left side end of machine shaft corresponds left bearing outer recess and is equipped with the locating groove, and the locating groove is equipped with the locating baffle of cooperation embedding, and the right side end surface of locating baffle is between left bearing left side end surface and is passed through left locating baffle friction cooperation, the concentric mounting hole of impeller and machine shaft left side end is opened, and the impeller is locked fixed with machine shaft through locating bolt, and the extension end of impeller along machine shaft left side end outer circumferential surface extends to machine shaft middle part direction, and the extension end sleeve is in machine shaft left side end portion and the right end surface of extension end and the left side end surface of locating baffle abut, the outer ring of right bearing is cooperated with fixed bolster, and the inner ring is cooperated with machine shaft, the fixed sleeve of machine shaft right end end portion outer circumferential surface place is set up, and the right end position of machine shaft corresponds fixed sleeve and is opened with the baffle groove, and the welding baffle of fixed sleeve and machine shaft fixed position is fixed in baffle groove, and the right side end surface of right bearing inner ring and the left side end surface of fixed sleeve are between friction cooperation and are equipped with right locating baffle.

[0008] In the above scheme, on the basis of the original structure of installing the baffle by slotting, the original impeller is prolonged, on the one hand, the extension end sleeve is in the left side end of the machine shaft, which can form an installation cavity when the impeller and the left side of the machine shaft are fixed, and assists the positioning of the left side of the machine shaft, making the installation of the machine shaft more stable and reliable, on the other hand, the extension end can abut on the locating baffle, providing a limit for the axial positioning of the locating baffle from the left side, and providing a limit for the axial positioning of the inner ring of the left bearing, cooperating with the fixed sleeve at the right bearing, the machine shaft and the fixed bolster can be axially limited from both ends of the machine shaft, and the positioning of the machine shaft and the fixed bolster is more stable and reliable.

[0009] Further, the fixed bolster has a stepped surface in each of the left and right ends, and the outer rings of the left and right bearings are matched with the stepped surfaces of the corresponding ends and are arranged in the cavities formed by the stepped surfaces and the outer circumferential surface of the machine shaft.

[0010] Further, the stepped surface has an inclined guide surface between the side surface of the cavity inner wall and the outer end surface of the fixed bolster. The inclined guide surface can provide a guide for the cooperation between the bearing and the fixed bolster, facilitating the positioning and installation of the bearing.

[0011] Further, on the right side of the machine shaft, the right end of the machine shaft, the outer end of the fixed sleeve, and the welding baffle are welded and fixed.

[0012] Further, the left end of the shaft has a three-stage variable-diameter structure at a position from the retainer groove, including a first small-diameter section, a second variable-diameter section, and a third large-diameter section, wherein the diameter of the third large-diameter section is larger than that of the first small-diameter section, and the diameter of the second variable-diameter section is gradually increased from the first small-diameter section to the third large-diameter section. The variable-diameter structure of the second variable-diameter section can guide the cooperation between the extension end and the left end of the shaft, and facilitate the stable and reliable cooperation of the outer sleeve at the third large-diameter section.

[0013] Further, in the cooperation between the left end of the shaft and the extension end, the inner circumferential surface of the extension end is wrapped around the left end of the shaft, and the extension end also has a small-diameter section, a variable-diameter section, and a large-diameter section, wherein the axial length of the small-diameter section of the extension end is smaller than that of the first small-diameter section of the shaft, and the variable-diameter section of the extension end and the second variable-diameter section of the shaft form a transition gap for the transition of the cooperation between the extension end and the shaft.

[0014] An outer rotor motor includes an outer rotor, a shaft, a fixed support, and an inner stator, wherein the inner stator is fixed on the fixed support, the positioning structure between the shaft and the fixed support adopts the shaft fixing structure according to any one of claims 1 to 6, and the outer rotor is fixedly connected with the shaft.

[0015] The shaft fixing structure and the outer rotor motor have the following advantages: the structure is reasonable, the extension end of the impeller provides a pressing force for the positioning retainer at the left bearing position, so that the positioning retainer can effectively press the left positioning block, thereby effectively pressing the inner ring of the left bearing, the fixed sleeve and the welded retainer are cooperated at the right bearing position to effectively position the position outside the right positioning block, the left bearing and the right bearing can be effectively positioned in the axial direction, the fixed support and the shaft are accurately positioned in the axial direction, and the cooperation is stable and good, and the fixed support does not interfere with the rotation of the shaft. The outer rotor motor using the shaft fixing structure is more stable and reliable in operation, and can be applied to axial flow fans, fans and other occasions. BRIEF DESCRIPTION OF DRAWINGS

[0016] The utility model is further described below in combination with the drawings and examples.

[0017] Figure 1 is a structural schematic view of the outer rotor motor of the utility model.

[0018] Figure 2 is Figure 1 a sectional view of A-A in figure 2.

[0019] Figure 3 is Figure 2 an enlarged schematic view of B in figure 2.

[0020] Figure 4 isFigure 2 Enlarged diagram of point C in the middle.

[0021] Figure 5 This is a perspective view of the shaft fixing mechanism of this utility model (excluding the fixing bracket).

[0022] Figure 6 This is a perspective view (excluding the fixing bracket) of the shaft fixing structure of this utility model from another direction.

[0023] Figure 7 This is a front view of the impeller in the shaft fixing structure of this utility model (excluding the fixing bracket).

[0024] Figure 8 yes Figure 7 A cross-sectional view of DD (excluding the fixed support).

[0025] In the figure: 1. Fixed bracket; 2. Inner stator; 3. Shaft; 4. Outer rotor; 5. Impeller; 6. Positioning retaining ring; 7. Left positioning block; 8. Left bearing; 9. Right bearing; 10. Right positioning block; 11. Fixed sleeve; 12. Welded retaining ring; 13. First-stage small diameter section; 14. Second-stage variable diameter section; 15. Third-stage large diameter section; 16. Extension end. Detailed Implementation

[0026] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the present invention. Therefore, they only show the components relevant to the present invention. Orientations and references (e.g., up, down, left, right, etc.) are only used to aid in the description of the features in the drawings. Therefore, the following specific embodiments are not intended to be restrictive, and the scope of the claimed subject matter is defined solely by the appended claims and their equivalents.

[0027] like Figure 2 , Figure 3 and Figure 4 The shaft fixing structure shown is an embodiment of this utility model.

[0028] like Figure 5 to Figure 8As shown, the machine shaft fixing structure includes an impeller 5, a machine shaft 3 and a fixing support 1. The fixing support 1 is fixed with an inner stator 2, and the outer stator 2 is provided with an outer rotor 4 which can rotate relative to the inner stator 2. The impeller 5 is arranged at the left end of the machine shaft 3. The machine shaft 3 and the fixing support 1 are rotatably connected through bearings designed at both ends, respectively including a left bearing 8 and a right bearing 9. The fixing support 1 is concave at both ends and has a stepped surface. The outer rings of the left bearing 8 and the right bearing 9 are respectively matched with the stepped surfaces of the corresponding ends and are arranged in the cavities formed by the stepped surfaces and the outer circumferential surface of the machine shaft 3. The side surface of the stepped surface corresponding to the inner wall of the cavity and the outer end surface of the fixing support 1 have an inclined guide surface. Through the inclined guide surface, the cooperation between the bearing and the fixing support 1 is guided, and the positioning and installation of the bearing are facilitated.

[0029] As shown in Figure 3 and Figure 8 In the cooperation between the machine shaft 3 and the left end of the fixing support 1, the outer ring of the left bearing 8 is matched with the fixing support 1, and the inner ring is matched with the machine shaft 3. The left end of the machine shaft 3 is concave and has a positioning groove corresponding to the outer ring of the left bearing 8. A positioning check ring 6 is embedded in the positioning groove. The right end surface of the positioning check ring 6 is frictionally matched with the left end surface of the left bearing 8 through a left positioning block 7. In the cooperation between the outer ring of the left bearing 8 and the fixing support 1, a check ring can also be frictionally matched between the outer ring of the left bearing 8 and the fixing support 1, further increasing the positioning effect of the outer ring of the left bearing 8 and the fixing support 1.

[0030] In the installation of the positioning check ring 6, on the one hand, the positioning groove provides a space for embedding installation, and on the other hand, the installation of the impeller 5 provides a pressure limiting position for the positioning check ring 6 from the left end surface. Specifically, the impeller 5 and the left end of the machine shaft 3 are provided with concentric mounting holes. The impeller 5 and the machine shaft 3 are locked and fixed through positioning bolts and the mounting holes on the impeller 5 and the machine shaft 3. The impeller 5 extends along the outer circumferential surface of the left end of the machine shaft 3 to the middle part of the machine shaft 3 and has an extension end 16. The extension end 16 is sleeved on the left end of the machine shaft 3, and the right end surface of the extension end 16 abuts against the left end surface of the positioning check ring 6. In this end position, the impeller 5 which originally must exist is lengthened. On the one hand, the installation and positioning of the machine shaft 3 and the impeller 5 are completed, that is, the extension end 16 is sleeved on the left end of the machine shaft 3, forming an installation cavity when the impeller 5 and the machine shaft 3 are fixed on the left side, assisting the positioning of the left side of the machine shaft 3, making the installation of the machine shaft 3 more stable and reliable. On the other hand, the extension end 16 also has a limiting effect on the axial positioning of the machine shaft 3 and the fixing support 1, that is, the extension end 16 is lengthened and abuts against the positioning check ring 6, providing a limiting position for the axial positioning of the positioning check ring 6 from the left side, providing a limiting position for the axial positioning of the inner ring of the left bearing 8, cooperating with the fixing sleeve 11 at the right bearing 9, and limiting the axial positioning of the machine shaft 3 and the fixing support 1 from both ends of the machine shaft 3. The positioning of the machine shaft 3 and the fixing support 1 is more stable and reliable.

[0031] As shown in Figure 4 andFigure 8 As shown, in the fit between the machine shaft 3 and the right end of the fixed bracket 1, the outer ring of the right bearing 9 fits with the fixed bracket 1, and the inner ring fits with the machine shaft 3. A fixed sleeve 11 is fitted on the outer circumferential surface of the right end of the machine shaft 3. A retaining ring groove is opened on the machine shaft 3 corresponding to the right end position of the fixed sleeve 11. A welded retaining ring 12 is fixed in the retaining ring groove to position and fix the fixed sleeve 11 and the machine shaft 3. A right positioning block 10 is provided between the right end face of the inner ring of the right bearing 9 and the left end face of the fixed sleeve 11 in frictional fit. The right end of the machine shaft 3 is welded and fixed to the outer end of the fixed sleeve 11 and the welded retaining ring 12. When the machine shaft 3, the fixed sleeve 11, and the welded retaining ring 12 are fixed, the right end face of the right positioning block 10 is limited, and its left end face is in frictional fit with the right end face of the inner ring of the right bearing 9. This achieves axial fixation between the fixed bracket 1 and the machine shaft 3 at the right end position of the machine shaft 3, and the fixed bracket 1 does not interfere with the smooth rotation of the machine shaft 3.

[0032] In the actual design, the outer stator 4 can be positioned and fixed to the right end of the machine shaft 3 by the connecting piece. When working, the outer stator 4 rotates relative to the inner stator 2, driving the machine shaft 3 to rotate, thereby realizing the rotation operation of the machine shaft 3 relative to the fixed bracket 1.

[0033] Based on the above-mentioned fixed structure, the fit between the left end of the machine shaft 3 and the impeller 5 can be further designed to make it more convenient and reliable during installation.

[0034] Specifically, such as Figure 3 As shown, from the left end of the machine shaft 3 to the retaining ring groove, the machine shaft 3 is designed with a three-stage variable diameter structure, namely a primary small diameter section 13, a secondary variable diameter section 14, and a tertiary large diameter section 15. The primary small diameter section 13 and the tertiary large diameter section 15 are cylindrical structures, with the diameter of the tertiary large diameter section 15 being larger than that of the primary small diameter section 13. The diameter of the secondary variable diameter section 14 transitions from small to large, connecting the primary small diameter section 13 and the tertiary large diameter section 15. The variable diameter structure of the secondary variable diameter section 14 provides guidance for the fit between the extension end 16 and the left side of the machine shaft 3, facilitating a stable and reliable outer fitting at the tertiary large diameter section 15.

[0035] The inner circumferential surface of the extension end 16 surrounds the left end of the machine shaft 3, and also has a small-diameter section, a variable-diameter section, and a large-diameter section. The axial length of the small-diameter section of the extension end 16 is less than the axial length of the first-stage small-diameter section 13 of the machine shaft 3. A transition gap is formed between the variable-diameter section of the extension end 16 and the second-stage variable-diameter section 14 of the machine shaft 3 to facilitate the connection and fit between the extension end 16 and the machine shaft 3. This transition gap provides guidance for the fit between the machine shaft 3 and the extension end 16, and also provides a certain margin for the fit, which is more conducive to the positioning and fixing of the extension end 16 and the machine shaft 3.

[0036] Based on the aforementioned shaft fixing structure, this application also provides, as well as...Figure 1 and Figure 2 An outer rotor motor.

[0037] The outer rotor motor comprises an outer rotor 4, a shaft 3, an inner stator 2 and a fixed support 1. The inner stator 2 is fixedly arranged on the fixed support 1, and the positioning structure between the shaft 3 and the fixed support 1 adopts the above-mentioned shaft fixing structure. The outer rotor 4 is fixedly connected with the right end of the shaft 3. During the operation of the motor, the shaft 3 is axially positioned relative to the fixed support 1 and the inner stator 2, and the shaft 3 synchronously rotates relative to the impeller 5 and the outer rotor 4, and the rotation is smooth and without interference, and is stable and reliable. At this time, when the outer rotor motor is used for a fan and an impeller, the rotating assembly of the fan and the impeller can be installed at the impeller 5 end of the shaft 3, and the rotating assembly rotates with the rotation of the shaft 3 and the outer rotor 4. The fixed support 1 is fixedly positioned with the external fixed shell, and plays a role of stable support, so that the action of the fan and the impeller is realized, and the rotating part is not easy to move during the effective rotation, and the rotation operation is more smooth, stable and reliable.

[0038] According to the above ideal embodiments of the present application, the related personnel can make various changes and modifications without deviating from the technical idea of the present application. The technical scope of the present application is not limited to the content of the specification, and must be determined according to the scope of the claims.

Claims

1. A shaft fixing structure, comprising an impeller (5), a shaft (3), and a fixing bracket (1), wherein an inner stator (2) is provided on the fixing bracket (1), and an outer rotor rotating relative to the inner stator (2) is provided outside the inner stator (2), and the impeller (5) is disposed at the left end of the shaft (3), characterized in that: It comprises a left bearing (8) and a right bearing (9); The outer ring of the left bearing (8) is matched with the fixed support (1), and the inner ring is matched with the shaft (3); the left end of the shaft (3) is provided with a positioning groove corresponding to the outer and inner recesses of the left bearing (8), and a positioning retainer (6) is embedded in the positioning groove; the left end face of the positioning retainer (6) is frictionally matched with the left end face of the left bearing (8) through a left positioning block (7); the impeller (5) and the left end of the shaft (3) are provided with concentric mounting holes; the impeller (5) is locked and fixed with the shaft (3) through positioning bolts; the impeller (5) extends along the outer circumferential surface of the left end of the shaft (3) to the middle part of the shaft (3) and has an extension end (16); the extension end (16) is sleeved on the left end of the shaft (3), and the right end face of the extension end (16) abuts against the left end face of the positioning retainer (6); The outer ring of the right bearing (9) is matched with the fixed support (1), and the inner ring is matched with the shaft (3); a fixed sleeve (11) is sleeved on the outer circumferential surface of the right end of the shaft (3); the shaft (3) is provided with a retainer groove at the right end position corresponding to the fixed sleeve (11); a welded retainer (12) is fixed in the retainer groove to position and fix the fixed sleeve (11) and the shaft (3); a right positioning block (10) is frictionally matched between the right end face of the inner ring of the right bearing (9) and the left end face of the fixed sleeve (11).

2. The axle securing structure of claim 1, wherein: The left and right ends of the fixed support (1) are respectively provided with stepped faces; the outer rings of the left bearing (8) and the right bearing (9) are respectively matched with the stepped faces of the corresponding ends and are arranged in the cavities formed by the stepped faces and the outer circumferential surface of the shaft (3).

3. The axle securing structure of claim 2, wherein: The stepped faces have inclined guide surfaces between the side faces of the cavity inner walls and the outer end faces of the fixed support (1).

4. The axle securing structure of claim 1, wherein: The right end of the shaft (3) is welded with the outer end of the fixed sleeve (11) and the welded retainer (12).

5. The axle securing structure of claim 1, wherein: The left end of the shaft (3) to the retainer groove position has a three-stage variable diameter structure, which comprises a first small diameter section (13), a second variable diameter section (14) and a third large diameter section (15); the diameter of the third large diameter section (15) is greater than that of the first small diameter section (13), and the diameter of the second variable diameter section (14) is gradually increased from the first small diameter section (13) to the third large diameter section (15).

6. A spindle fixing structure according to claim 5, wherein: The inner circumferential surface of the extension end (16) is wrapped around the left end of the shaft (3) and also has a small diameter section, a variable diameter section and a large diameter section; the axial length of the small diameter section of the extension end (16) is smaller than that of the first small diameter section (13) of the shaft (3); a transition gap is formed between the variable diameter section of the extension end (16) and the second variable diameter section (14) of the shaft (3) for the transition connection of the extension end (16) and the shaft (3).

7. An external rotor electric machine characterized by: The motor comprises an outer rotor (4), a shaft (3), a fixed support (1) and an inner stator (2), the inner stator (2) is fixed on the fixed support (1), the positioning structure between the shaft (3) and the fixed support (1) adopts the shaft fixing structure as claimed in any one of claims 1 to 6, and the outer rotor (4) is fixedly connected with the shaft (3).

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