blower

Abstract

The present invention provides a blower with high output performance, which can centrally configure components that maintain vibration resistance and airtightness, reduce the number of components and the number of assembly steps, and thus can be mass-produced at low cost. A stator core (5a) is assembled to the inner wall surface (7f) of a first motor housing (7a) via a seal (12) covering the outer peripheral surface and axial end edges of the stator core. The axial end edges (12a) of the seal (12) are respectively clamped and assembled by protruding wall portions (4g, 7e) provided on the fan housing (4) and the motor housing (7) in a manner that flattens the axial end edges (12a) of the seal (12).

Description

Technical Field

[0001] The present invention relates to an air blower used for medical equipment, industrial equipment, consumer equipment and the like. Background Art

[0002] Conventional fans (blowers) are being miniaturized while also being required to achieve higher performance, such as higher pressure, higher flow rate, and higher responsiveness. Consequently, the trend is towards smaller impeller diameters and faster rotation speeds.

[0003] The blower is integrally assembled with a fan housing that houses an impeller and is provided with an air flow path, and a motor housing that houses a motor that rotationally drives the impeller.

[0004] The motor is started, and external air is sucked into the fan casing from the axial direction by the rotation of the impeller, and is discharged from the air supply passage provided on the radially outer side.

[0005] Although a vibration-proof member is provided between the motor housing and the equipment in which the motor housing is assembled, external air drawn into the fan housing axially by the rotation of the impeller may cause high-pressure fluid to leak into the motor housing through, for example, the gap around the motor shaft, resulting in a problem in which the desired static pressure cannot be obtained.

[0006] Although the motor case is configured so that a vibration-proof member is provided between the motor case and the device to which the motor case is mounted, fluid leaking from the motor case is not sealed.

[0007] In order to improve the airtightness of the motor housing, it is arranged to bond the motor structural components (such as the stator core) separately from the vibration-proof components, or to compress seals such as O-rings in the radial and axial directions inside the motor, thereby ensuring both vibration-proofing and airtightness.

[0008] A blower is proposed, for example, in which a motor is supported and fixed to a housing at multiple locations via a first elastic member that can be elastically deformed. In addition, a second elastic member that can be elastically deformed is provided to seal a gap between the housing and the motor to prevent air leakage from the gap, thereby preventing air leakage while absorbing vibration of the blower (refer to patent document 1: Japanese Patent Gazette No. 2002-21797).

[0009] Prior art literature

[0010] Patent Literature

[0011] Patent Document 1: Japanese Patent Application Laid-Open No. 2002-21797

[0012] However, as described in Patent Document 1, providing multiple elastic members with different elastic coefficients to maintain the vibration resistance and airtightness of the motor housing increases the number of parts and the number of assembly steps, thereby increasing manufacturing costs. Furthermore, due to the time-dependent changes in the elastic coefficients of some of the elastic members, it is possible that the sealing performance may no longer be maintained. Summary of the Invention

[0013] The present invention is made to solve the above-mentioned technical problems, and its purpose is to provide a blower with higher output performance, which can centrally configure components that maintain vibration resistance and airtightness, reduce the number of components and also reduce the assembly process, and mass-produce inexpensively.

[0014] In order to solve the above technical problems, the present invention at least includes the following structures.

[0015] A blower is integrally assembled with: a fan casing that accommodates an impeller and is provided with an air supply path, and a motor casing that accommodates an electric motor that drives the impeller to rotate. The rotation of the impeller draws external air into the fan casing axially and discharges the external air from the air supply path provided on the radial outside. The stator core is assembled to the inner wall surface of the motor casing via a seal covering the outer peripheral surface and axial end edges of the stator core. The axial end edges of the seal are clamped and assembled by protruding walls provided relatively to the fan casing and the motor casing in a manner that flattens the axial end edges of the seal.

[0016] According to the above structure, since the protruding wall portions relatively provided on the fan casing and the motor casing respectively clamp the axial end edge portions of the seal in a manner of flattening the axial end edge portions of the seal, the seal can absorb the vibration transmitted from the stator and the rotor to the motor casing and the fan casing, thereby ensuring vibration resistance. Based on this, the seal flattened by the pair of axially opposite protruding wall portions is deformed radially inward and radially outward, thereby improving the close contact with the stator core and the motor casing, so that the fluid that is about to leak from the motor can be sealed, thereby improving the airtightness.

[0017] Furthermore, since the seals that improve airtightness and vibration resistance are concentratedly arranged on the inner wall surface of the motor case, the number of parts can be reduced and the number of assembly steps can be reduced, thereby enabling inexpensive mass production.

[0018] Alternatively, in the fan casing, the first protrusion portion and the second protrusion portion are annularly protruded with a specified interval on the radial inner side and the radial outer side, and a groove is formed between the pair of protrusion portions, the casing opening end of the motor casing is inserted into the groove, and the outer peripheral surface of the first protrusion portion is embedded in the inner peripheral surface of the motor casing in an overlapping manner, thereby completing radial positioning.

[0019] In this way, radial positioning is achieved by making the outer peripheral surface of the first protrusion part fit into the inner peripheral surface of the motor housing in an overlapping manner, thereby improving assemblability. The radial gap between the fan housing and the motor housing is minimized by inserting the housing opening end of the motor housing into the groove and fitting it into a maze shape, thereby improving air tightness.

[0020] The second protruding wall portion may be pressed by a flange portion protruding from the outer peripheral surface of the motor housing, thereby completing axial positioning and performing assembly.

[0021] In this way, by positioning and fitting the fan housing and the motor housing in the axial direction, the assemblability can be improved, and the airtightness can be improved by minimizing the gap in the axial direction.

[0022] The pressing surfaces of the protruding wall portions, which are respectively provided on the fan housing and the motor housing in an axially opposed manner, are preferably rounded. Thus, when the axial end edges of the seal are respectively flattened by the pair of protruding wall portions, the seal is actively deformed so that the axial wall thickness of the seal bulges radially inward and radially outward, thereby improving the close contact between the seal and the outer circumferential surface of the stator core and the inner circumferential surface of the motor housing, thereby enhancing airtightness. Furthermore, since the seal improves the close contact between the outer circumferential surface of the stator core and the inner circumferential surface of the motor housing, and the seal improves the close contact between the axial end face of the stator core and the fan housing, heat generated by the stator can be transferred to the motor housing and the fan housing, thereby maintaining heat dissipation.

[0023] The seal is preferably made of an annular elastic member such as vibration-proof rubber or elastomer, thereby improving vibration-proofing and airtightness with a small number of parts and the use of inexpensive materials.

[0024] A blower with high output performance can be provided, in which components for maintaining vibration resistance and airtightness can be centrally arranged, the number of components can be reduced, and the number of assembly steps can be reduced, thereby enabling inexpensive mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] FIG1 is an axial cross-sectional view and a partially enlarged cross-sectional view of the blower. DETAILED DESCRIPTION

[0026] Hereinafter, an embodiment of the blower of the present invention will be described with reference to the accompanying drawings. Figure 1A 、 1B The schematic structure of the blower is described.

[0027] The blower 1 includes the following structures. Figure 1AAs shown, a fan housing 4 housing an impeller 2 and forming an air flow path 3 and a motor housing 7 housing a stator 5 and a rotor 6 (motor M) are integrally screwed and fixed by fixing screws 8a.

[0028] The blower 1 starts the motor M and draws outside air into the fan case 4 from the axial direction by the rotation of the impeller 2, and discharges it from the air supply path 3 provided on the radially outer side.

[0029] exist Figure 1A In the figure, the fan housing 4 is formed as a whole by thermally welding the concave and convex fitting parts formed on the end surfaces of the first fan housing 4a and the second fan housing 4b. An air inlet 4c is formed in the center of the first fan housing 4a. At the central opening of the second fan housing 4b, the cylindrical bearing holder 9 is stopped by the sleeve 9a arranged concentrically on the outside and is assembled as a whole via the buffer 9b. A pair of bearings 10 are assembled in the bearing holder 9. The pair of bearings 10 use rolling bearings, for example. The shaft 11 is embedded in and rotatably supported by the above-mentioned pair of bearings 10. The pair of bearings 10 are respectively positioned and assembled in the axial direction relative to the shaft 11 by anti-slip washers. One end side of the shaft 11 enters the fan housing 4, and the impeller 2 is assembled as a whole to the above-mentioned one end side by pressing, bonding, or using the above-mentioned methods.

[0030] The disc-shaped main plate 2a of the impeller 2 has blades 2b extending from the center toward the periphery at multiple locations. A shroud 2c connects the raised ends of each blade 2b and is formed opposite the recessed portion 4d on the top surface of the first fan case 4a. The outer peripheral end of the main plate 2a extends to a position facing the air supply path 3. Furthermore, the second fan case 4b is provided with a flow guide 3a, which forms the air supply path 3 for the compressed air supplied thereto into a circular cross-section.

[0031] A first curved portion 4e provided on the outer circumference of the first fan housing 4a and a second curved portion 4f provided on the outer circumference of the second fan housing 4b are combined to form the air supply path 3. Air drawn in through the air inlet 4c passes along the blades 2b of the impeller 2 through the air supply path surrounded by the shroud 2c and the main plate 2a, is accelerated toward the outer circumference of the main plate 2a, and is then fed into the air supply path 3 extending axially downward from the main plate 2a.

[0032] Below the second curved portion 4f of the second fan case 4b, a first protruding wall portion 4g and a second protruding wall portion 4h are provided in an annular shape, radially inward and radially outward, with a predetermined interval therebetween. A recessed groove 4i is formed between the pair of protruding wall portions 4g and 4h. As will be described later, the opening end of the motor case 7 (first motor case 7a) is inserted into this recessed groove 4i, with the outer circumferential surface of the first protruding wall portion 4g fittingly overlapping the inner circumferential surface of the motor case 7, thereby positioning the motor in the radial direction.

[0033] The motor case 7 includes a cylindrical first motor case 7a assembled to the fan case 4 (second fan case 4b) and a second motor case 7b that closes the open end of the first motor case 7a.

[0034] A flange 7c protrudes from the outer circumference of the first motor housing 7a. The second protruding wall 4h of the second fan housing 4b abuts against this flange 7c, thereby completing the axial positioning of the fan housing 4 and the motor housing 7 and assembling them. The threaded holes provided in the flange 7c and the second protruding wall 4h are aligned and screwed into place with the fixing screws 8a, thereby integrally assembling the fan housing 4 and the motor housing 7.

[0035] A flange portion 7d protrudes from the outer circumference of the second motor housing 7b. The end face of the first motor housing 7a is brought into contact with the flange portion 7d, and the fixing screws 8b are threadedly engaged with the threaded holes aligned, thereby integrally assembling the first and second motor housings 7a and 7b. An annular motor protrusion 7e protrudes axially from the inner circumference of the flange portion 7d of the second motor housing 7b. This motor protrusion 7e protrudes axially opposite the first protrusion 4g of the fan housing 4.

[0036] The stator 5 is assembled to the inner wall surface 7f of the first motor housing 7a via a seal 12. Specifically, the stator 5 is assembled to the inner wall surface 7f of the first motor housing 7a via seals 12 covering the outer circumference and axial end edges of the stator core 5a. The seal 12 can be made of an annularly molded elastic member such as vibration-damping rubber or an elastomer (e.g., EPDM (ethylene propylene diene rubber)). This ensures vibration isolation by absorbing vibrations transmitted from the stator 5 and rotor 6 to the motor housing 7 and fan housing 4.

[0037] An annular core back portion 5b is fixed to the inner wall surface 7f of the first motor housing 7a via a seal 12, and the stator core 5a is assembled. Pole teeth 5c are provided at multiple locations protruding radially inward from the annular core back portion 5b. The stator core 5a is covered with an insulator 5d, and a coil 5e is wound around each pole tooth 5c via the insulator 5d. The pole teeth 5c of the stator core 5a are arranged opposite to the rotor magnet 6b. The motor substrate 13 is held by the insulator 5d. Coil leads drawn from each coil 5e are connected to the motor substrate 13, and a Hall IC 13a for detecting the magnetic pole position of the rotor is installed. In addition, a lead wire 14 for power supply is connected to the motor substrate 13. The lead wire 14 is led to the outside through a grommet 15 provided at the opening of the second motor housing 7b and is wired.

[0038] The other end of the shaft 11 enters the motor housing 7. The rotor 6 is assembled to the other end of the shaft 11. Specifically, the rotor magnet 6b is concentrically mounted on the shaft 11 via the rotor yoke 6a. The rotor magnet 6b is alternately excited with an N pole and an S pole in the circumferential direction. In the rotor 6, the position detection magnet 16 is assembled to the other end of the shaft 11 in an axially secured state. The magnetic poles of the position detection magnet 16 correspond to those of the rotor magnet 6b, and the rotor position is detected by the Hall IC 13a arranged opposite to each other on the motor substrate 13.

[0039] As described above, when the fan housing 4 and the motor housing 7 are integrally assembled, the first protruding wall portion 4g of the fan housing 4 and the motor protruding wall portion 7e provided on the motor housing 7 respectively sandwich the axial end edges 12a of the seal 12 in such a manner as to flatten the axial end edges 12a of the seal 12. Specifically, as Figure 1B As shown in the enlarged cross-sectional view of FIG, the front end pressing portion 4g1 of the first protruding wall portion 4g is formed into a rounded surface (the motor protruding wall portion 7e is also formed in the same manner and therefore not shown). Therefore, when the first protruding wall portion 4g and the motor protruding wall portion 7e sandwich the axial end edges 12a of the opposing seal 12, they deform so that the axial wall thickness of the compressed seal 12 is reduced and the seal 12 is actively bulged radially inward and radially outward as indicated by the left and right arrows.

[0040] Thus, vibration transmitted from the stator 5 and rotor 6 to the motor housing 7 and fan housing 4 can be absorbed by the seal 12, thereby ensuring vibration isolation. Based on this, the seal 12, which is flattened by the pair of axially opposing protruding wall portions 4g and 7e, is deformed radially inward and radially outward, thereby improving the close contact with the outer peripheral surface of the stator core 5a (core back portion 5b) and the inner peripheral surface of the first motor housing 7a. This can seal fluid that attempts to leak from the motor housing 7 and improve airtightness. In addition, by concentrating the seal 12 that improves airtightness and vibration isolation on the inner wall surface 7f of the first motor housing 7a, the number of parts can be reduced, and the number of assembly steps can also be reduced, thereby enabling inexpensive mass production.

[0041] The housing opening end of the first motor case 7a is inserted into the groove 4i between the first protruding wall portion 4g and the second protruding wall portion 4h, and the first protruding wall portion 4g overlaps with the inner wall surface 7f of the first motor case 7a, thereby completing radial positioning.

[0042] In this way, by making the outer peripheral surface of the first protruding wall portion 4g fit into the inner peripheral surface of the first motor housing 7a in an overlapping manner, the radial gap between the fan housing 4 and the motor housing 7 can be reduced as much as possible and positioned and assembled in the radial direction, thereby improving the assemblability. Based on this, by inserting the housing opening end of the motor housing 7 into the groove 4i and fitting it into a maze shape, the air tightness can also be improved.

[0043] In addition, since the second protruding wall portion 4h is pressed by the flange portion 7c protruding from the outer wall of the first motor housing 7a for axial positioning and assembly, the assembly performance can be improved, and the axial gap between the fan housing 4 and the motor housing 7 can be reduced as much as possible, thereby improving the airtightness.

[0044] In addition, the seal 12 is deformed in such a manner that the axial wall thickness is actively released radially inward and radially outward, thereby improving the close contact between the outer peripheral surface of the stator core 5a and the inner peripheral surface of the motor housing 7 through the seal 12, and improving the close contact between the axial end surface of the stator core 5a and the fan housing 4 through the seal 12. Therefore, the heat generated by the stator 5 can also be transferred to the motor housing 7 and the fan housing 4 to maintain heat dissipation.

[0045] Furthermore, although the case where the pair of bearings 10 are rolling bearings is illustrated, the present invention is not limited thereto and may be other bearings such as a fluid dynamic bearing or a sliding bearing.

Claims

1. A blower integrally assembled with: a fan housing that houses an impeller and is provided with an air supply path, and a motor housing that houses a motor that drives the impeller to rotate, wherein external air is drawn axially into the fan housing by the rotation of the impeller and discharged from the air supply path provided radially outward, characterized in that: The stator core is assembled to the inner wall surface of the motor housing via a seal covering the outer peripheral surface and the axial end edges of the stator core. The axial end edges of the seal are flattened and deformed by the protruding walls relatively provided on the fan housing and the motor housing, respectively, so that the axial wall thickness of the seal is reduced and bulges radially inward and radially outward, thereby performing assembly.

2. The blower according to claim 1, wherein: In the fan casing, the first protrusion portion and the second protrusion portion are annularly protruded with a specified interval on the radial inner side and the radial outer side, and a groove is formed between the pair of protrusion portions. The housing opening end of the motor casing is inserted into the groove, and the outer peripheral surface of the first protrusion portion is embedded in the inner peripheral surface of the motor casing in an overlapping manner, thereby completing radial positioning.

3. The blower according to claim 2, wherein: The second protruding wall portion is pressed by a flange portion protruding from the outer peripheral surface of the motor housing, thereby completing axial positioning and performing assembly.

4. The blower according to any one of claims 1 to 3, characterized in that The pressing surfaces of the protruding wall portions provided on the fan housing and the motor housing so as to face each other in the axial direction are rounded surface shapes.

5. The blower according to any one of claims 1 to 3, characterized in that: The seal is formed of an annular elastic member, and the elastic member is formed of vibration-proof rubber.

6. The blower according to any one of claims 1 to 3, characterized in that: The seal is formed of an annular elastic member, and the elastic member is formed of an elastomer.

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