1. The air blower is characterized by comprising a motor shaft system, a motor outer cylinder (12), a motor inner cylinder (13), a motor stator (14), a first end cover (15), a second end cover (16) and an axial air bearing (17); the first end cover (15) and the second end cover (16) are respectively fixed at two ends of the motor outer cylinder (12), the outer wall of the motor inner cylinder (13) is nested into an inner hole of the motor outer cylinder (12), and the motor stator (14) is fixed on the motor inner cylinder (13); the motor shaft system comprises a motor shaft (1), a second rotating shaft (2) and a third rotating shaft (3); the motor shaft (1) is provided with a motor rotor (11), and one end of the second rotating shaft (2) and one end of the third rotating shaft (3) are respectively and fixedly connected to the two ends of the motor shaft (1) in a coaxial mode; a second air radial bearing (21), a thrust disc (22), a heat dissipation impeller (23) and a second locking nut (24) are sequentially fixedly sleeved on the second rotating shaft (2) from the inner side to the outer side in the axial direction, and a third air radial bearing (31), a blast impeller (32) and a third locking nut (33) are sequentially fixedly sleeved on the third rotating shaft (3) from the inner side to the outer side in the axial direction; the sum of products of the weights of the second rotating shaft (2), the thrust disc (22), the heat dissipation impeller (23) and the second locking nut (24) and the distance from the center of mass of the second rotating shaft to the center of the motor shaft (1) is equal to the sum of products of the weights of the third rotating shaft (3), the air blowing impeller (32) and the third locking nut (33) and the distance from the center of mass of the air blowing impeller to the center of the motor shaft (1).

2. A thrust bearing rear mounted air suspension blower as claimed in claim 1 wherein the second shaft (2) comprises a first shaft section (521), a second shaft section (522), a third shaft section (523) and a fourth shaft section (524); the outer walls of the first shaft section (521) and the fourth shaft section (524) are provided with external threads, and a second boss (54) is arranged at one end, located on the second rotating shaft (2), of the motor shaft (1); the second boss (54) is provided with an inner hole with internal threads, and the external threads of the first shaft section (521) and the internal threads of the inner hole of the second boss (54) are screwed to the joint position of the end surface of the inner side of the second shaft section (522) and the end surface of the outer side of the second boss (54).

3. A thrust bearing rear mounted air suspension blower as claimed in claim 2 wherein the outer wall of the second boss (54) is fitted with a second bushing (55); the second rotating shaft (2) penetrates through an inner hole of a second shaft sleeve (55), and the outer wall of the second shaft sleeve (55) is rotatably connected with a second air radial bearing (21); the second shaft sleeve (55) is provided with a second shaft sleeve boss (551), and the thrust disc (22) and the heat dissipation impeller (23) are sleeved on the outer wall of the second shaft sleeve boss (551); the second locking nut (24) is screwed with the external thread of the fourth shaft section (524); when the second locking nut (24) is locked, the second shaft sleeve (55) is axially locked on the second rotating shaft (2), and the thrust disc (22) and the heat dissipation impeller (23) are axially locked on the second shaft sleeve (55).

4. A thrust bearing rear mounted air suspension blower as claimed in claim 3 wherein the outer surface of the second hub (55) is provided with a PVD coating.

5. A thrust bearing rear mounted air suspension blower as claimed in claim 1 wherein the third shaft (3) comprises a fifth shaft segment (531), a sixth shaft segment (532), a seventh shaft segment (533) and an eighth shaft segment (534); the outer walls of the fifth shaft section (531) and the eighth shaft section (534) are provided with external threads, and a third boss (56) is arranged at one end, located on the third rotating shaft (3), of the motor shaft (1); an inner hole with an internal thread is formed in the third boss (56), and the external thread of the five shaft section (531) and the internal thread of the inner hole of the third boss (56) are screwed to the position where the end face of the inner side of the sixth shaft section (532) is attached to the end face of the outer side of the third boss (56).

6. A thrust bearing rear mounted air suspension blower as claimed in claim 5 wherein the outer wall of the third boss (56) is fitted with a third boss (57); the third rotating shaft (3) penetrates through an inner hole of the third shaft sleeve (57), and the outer wall of the third shaft sleeve (57) is rotatably connected with the third air radial bearing (31); the third shaft sleeve (57) is provided with a third shaft sleeve boss (571), the blast impeller (32) is sleeved on the outer wall of the third shaft sleeve boss (571), and the third locking nut (33) is screwed with the external thread of the eighth shaft section (534); when the third locking nut (33) is locked, the third shaft sleeve (57) is axially locked on the third rotating shaft (3), and the blast impeller (32) is axially locked on the third shaft sleeve (57).

7. A thrust bearing rear mounted air suspension blower as claimed in claim 6 wherein the outer surface of the third sleeve (57) is provided with a PVD coating.

8. A thrust bearing rear mounted air suspension blower as claimed in claim 3 or 6, characterized in that the second (55) and third (57) shaft sleeves are axially symmetrically distributed along the centre of mass of the motor shaft (1).

9. A thrust bearing rear mounted air suspension blower as claimed in claim 1 wherein the second air radial bearing (21) and the third air radial bearing (31) are fixed to the first end cap (15) and the second end cap (16), respectively.

10. A thrust bearing rear mounted air suspension blower as claimed in claim 1 wherein the second end cap (16) is provided with a first thrust disk recess (161) and a second thrust disk recess (162), the first thrust disk recess (161) and the second thrust disk recess (162) being disposed opposite each other on the thrust disk (22); the axial air bearing (17) is provided with an axial limiting part (171) used for limiting the axial position of the thrust disc (22), and the two axial limiting parts (171) are respectively fixed on the first thrust disc groove (161) and the second thrust disc groove (162).

Background

The air suspension centrifugal blower is a new concept blower, and adopts three core high-end technologies of an ultra-high speed direct connection motor, an air suspension bearing and a high-precision single-stage centrifugal impeller, so that a new era of high-efficiency, high-performance, low-noise and low-energy consumption blowers is created.

The Chinese invention patent application (publication No. CN112228361A, published: 20210115) discloses an air suspension centrifugal blower, which comprises a motor, a volute, an impeller shaft, a bearing rotating shaft, an air suspension radial bearing and an air suspension thrust bearing, wherein the front end and the rear end of a motor rotor are respectively in rotary connection with the air suspension radial bearing through the bearing rotating shaft, the bearing rotating shaft positioned at the front end of the motor is in rotary connection with the air suspension thrust bearing through a thrust disc, the friction surfaces of the bearing rotating shaft and the thrust disc are provided with PVD coatings, the friction coefficient of the PVD coatings is less than or equal to 0.1, and the thickness of the PVD coatings is 2-8 mu m; the friction surfaces of the air suspension radial bearing and the air suspension thrust bearing are provided with PTFE coatings, the friction coefficient of the PTFE coatings is less than or equal to 0.05, and the thickness of the PTFE coatings is 0.02 mm-0.05 mm. The invention has the advantages of compact structure, high efficiency, long service life, good stability, high starting and stopping times, low motor temperature rise and the like.

The prior art has the following defects: a thrust disc and a blast impeller in a motor shaft system are arranged on one side of a motor shaft, and a heat dissipation impeller is independently arranged on the other side of the motor shaft; the mass of the blast impeller is larger than that of the heat dissipation impeller, and the thrust disc is arranged on one side of the blast impeller with larger mass, so that the mass difference between two sides of the motor shaft is larger; therefore, the center of mass of the motor shaft system is not located at the center of the motor shaft but located on one side close to the blower impeller, and the air radial bearing on one side of the blower impeller is stressed greatly compared with the air radial bearing on one side of the heat dissipation impeller, so that the service life of a single air radial bearing is shortened.

Disclosure of Invention

The purpose of the invention is: aiming at the problems, the thrust disc is arranged on one side of the heat dissipation impeller, so that the center of mass of a motor shaft system is positioned at the center of a motor shaft; and further ensure that the air radial bearings on the two sides are stressed uniformly, and prolong the service life of the air radial bearings.

In order to achieve the purpose, the invention adopts the following technical scheme:

a thrust bearing rear-mounted air suspension blower comprises a motor shaft system, a motor outer cylinder, a motor inner cylinder, a motor stator, a first end cover, a second end cover and an axial air bearing; the first end cover and the second end cover are respectively fixed at two ends of the motor outer cylinder, the outer wall of the motor inner cylinder is nested to an inner hole of the motor outer cylinder, and the motor stator is fixed on the motor inner cylinder; the motor shaft system comprises a motor shaft, a second rotating shaft and a third rotating shaft; the motor shaft is provided with a motor rotor, and one end of the second rotating shaft and one end of the third rotating shaft are respectively and fixedly connected to the two ends of the motor shaft in a coaxial manner; the second rotating shaft is fixedly sleeved with a second air radial bearing, a thrust disc, a heat dissipation impeller and a second locking nut in sequence from the inner side to the outer side in the axial direction, and the third rotating shaft is fixedly sleeved with a third air radial bearing, a blast impeller and a third locking nut in sequence from the inner side to the outer side in the axial direction; the sum of products of the weights of the second rotating shaft, the thrust disc, the heat dissipation impeller and the second locking nut and the distance from the center of mass to the center of the motor shaft is equal to the sum of products of the weights of the third rotating shaft, the air blowing impeller and the third locking nut and the distance from the center of mass to the center of the motor shaft.

Preferably, the second rotating shaft comprises a first shaft section, a second shaft section, a third shaft section and a fourth shaft section; the outer wall of the first shaft section and the outer wall of the fourth shaft section are both provided with external threads, and a second boss is arranged at one end of the motor shaft, which is positioned on the second rotating shaft; the second boss is provided with an inner hole with internal threads, and the external threads of the first shaft section and the internal threads of the inner hole of the second boss are screwed to the position where the end surface of the inner side of the second shaft section is attached to the end surface of the outer side of the second boss.

Preferably, a second shaft sleeve is sleeved on the outer wall of the second boss; the second rotating shaft penetrates through an inner hole of the second shaft sleeve, and the outer wall of the second shaft sleeve is rotatably connected with the second air radial bearing; the second shaft sleeve is provided with a second shaft sleeve boss, and the thrust disc and the heat dissipation impeller are sleeved on the outer wall of the second shaft sleeve boss; the second locking nut is screwed with the external thread of the fourth shaft section; when the second locking nut is locked, the second shaft sleeve is axially locked on the second rotating shaft, and the thrust disc and the heat dissipation impeller are axially locked on the second shaft sleeve. The outer surface of the second shaft sleeve is provided with a PVD coating.

Preferably, the third rotating shaft comprises a fifth shaft section, a sixth shaft section, a seventh shaft section and an eighth shaft section; the outer wall of the fifth shaft section and the outer wall of the eighth shaft section are both provided with external threads, and a third boss is arranged at one end of the motor shaft, which is positioned on a third rotating shaft; the third boss is provided with an inner hole with internal threads, and the external threads of the five shaft sections and the internal threads of the inner hole of the third boss are screwed to the joint position of the end face of the inner side of the sixth shaft section and the end face of the outer side of the third boss.

Preferably, a third shaft sleeve is sleeved on the outer wall of the third boss; the third rotating shaft penetrates through an inner hole of the third shaft sleeve, and the outer wall of the third shaft sleeve is rotatably connected with a third air radial bearing; the third shaft sleeve is provided with a third shaft sleeve boss, the blast impeller is sleeved on the outer wall of the third shaft sleeve boss, and a third locking nut is screwed with the external thread of the eighth shaft section; when the third locking nut is locked, the third shaft sleeve is axially locked on the third rotating shaft, and the blast impeller is axially locked on the third shaft sleeve. The outer surface of the third shaft sleeve is provided with a PVD coating.

Preferably, the second shaft sleeve and the third shaft sleeve are axially symmetrically distributed along the center of mass of the motor shaft.

Preferably, the second air radial bearing and the third air radial bearing are fixed to the first end cover and the second end cover, respectively. The second end cover is provided with a first thrust disc groove and a second thrust disc groove, and the first thrust disc groove and the second thrust disc groove are oppositely arranged at two ends of the thrust disc; the axial air bearing is provided with axial limiting parts used for limiting the axial position of the thrust disc, and the two axial limiting parts are respectively fixed on the first thrust disc groove and the second thrust disc groove.

The air suspension blower with the rear thrust bearing has the advantages that:

the second rotating shaft, the thrust disc, the heat dissipation impeller, the second locking nut, the third rotating shaft, the blast impeller and the third locking nut are all revolving body parts, and the respective mass centers of the second rotating shaft, the thrust disc, the heat dissipation impeller, the second locking nut, the third rotating shaft, the blast impeller and the third locking nut are all positioned at a revolving center; meanwhile, the motor shaft, the second rotating shaft and the third rotating shaft are coaxially connected, namely the respective mass centers of the above revolving body parts are all positioned on the axis of the motor shaft; moreover, the sum of products of the respective weights of the second rotating shaft, the thrust disc, the heat dissipation impeller and the second lock nut and the distance from the center of mass to the center position of the motor shaft is equal to the sum of products of the respective weights of the third rotating shaft, the blower impeller and the third lock nut and the distance from the center of mass to the center position of the motor shaft; the influence of the part on the second rotating shaft on the center of mass of the motor shaft system is counteracted with the influence of the part on the third rotating shaft on the center of mass of the motor shaft system, so that the center of mass of the motor shaft system is kept at the center of the motor shaft; and then make the second air journal bearing of motor shaft both sides and third air journal bearing atress even, improve air journal bearing life.

Drawings

FIG. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a schematic structural diagram of a motor shaft system.

A-the position of the center of mass of the motor shaft system.

Detailed Description

The following describes in detail embodiments of the present invention with reference to the drawings.

Example 1

The air suspension blower with the rear-mounted thrust bearing as shown in fig. 1 and 2 comprises a motor shaft system, a motor outer cylinder 12, a motor inner cylinder 13, a motor stator 14, a first end cover 15, a second end cover 16 and an axial air bearing 17; the first end cover 15 and the second end cover 16 are respectively fixed at two ends of the motor outer cylinder 12, the outer wall of the motor inner cylinder 13 is nested into an inner hole of the motor outer cylinder 12, and the motor stator 14 is fixed on the motor inner cylinder 13; the motor shaft system comprises a motor shaft 1, a second rotating shaft 2 and a third rotating shaft 3; the motor shaft 1 is provided with a motor rotor 11, and one end of the second rotating shaft 2 and one end of the third rotating shaft 3 are respectively and fixedly connected to the two ends of the motor shaft 1 in a coaxial manner; the second rotating shaft 2 is fixedly sleeved with a second air radial bearing 21, a thrust disc 22, a heat dissipation impeller 23 and a second locking nut 24 in sequence from the inner side to the outer side in the axial direction, and the third rotating shaft 3 is fixedly sleeved with a third air radial bearing 31, a blast impeller 32 and a third locking nut 33 in sequence from the inner side to the outer side in the axial direction; the sum of products of the weights of the second rotating shaft 2, the thrust disk 22, the heat dissipation impeller 23 and the second lock nut 24 and the distance from the center of mass thereof to the center position of the motor shaft 1 is equal to the sum of products of the weights of the third rotating shaft 3, the blower impeller 32 and the third lock nut 33 and the distance from the center of mass thereof to the center position of the motor shaft 1. In this way, the locking direction of the second locking nut 24 and the third locking nut 33 is opposite to the shaft system running direction, and the locking function can be achieved during high-speed running. The second rotating shaft 2, the thrust disc 22, the heat dissipation impeller 23, the second locking nut 24, the third rotating shaft 3, the blast impeller 32 and the third locking nut 33 are all revolving body parts, and the respective mass centers of the second rotating shaft, the thrust disc 22, the heat dissipation impeller 23, the second locking nut 24, the third rotating shaft, the blast impeller 32 and the third locking nut 33 are all located at a revolving center; meanwhile, the motor shaft 1, the second rotating shaft 2 and the third rotating shaft 3 are coaxially connected, namely the respective mass centers of the above revolving body parts are all positioned on the axis of the motor shaft 1; moreover, the sum of products of the weights of the second rotating shaft 2, the thrust disk 22, the heat-dissipating impeller 23 and the second lock nut 24 and the distance from the center of mass thereof to the center position of the motor shaft 1 is equal to the sum of products of the weights of the third rotating shaft 3, the blower impeller 32 and the third lock nut 33 and the distance from the center of mass thereof to the center position of the motor shaft 1; namely, the influence of the parts on the second rotating shaft 2 on the center of mass of the motor shaft system is offset with the influence of the parts on the third rotating shaft 3 on the center of mass of the motor shaft system, so that the center of mass of the motor shaft system is kept at the center of the motor shaft 1; and then make the second air radial bearing 21 and the third air radial bearing 31 atress of motor shaft 1 both sides even, improve air radial bearing life.

As shown in fig. 2, the second rotating shaft 2 includes a first shaft section 521, a second shaft section 522, a third shaft section 523 and a fourth shaft section 524; the outer walls of the first shaft section 521 and the fourth shaft section 524 are both provided with external threads, and the motor shaft 1 is provided with a second boss 54 at one end of the second rotating shaft 2; the second boss 54 is provided with an inner hole with an internal thread, and the external thread of the first shaft section 521 and the internal thread of the inner hole of the second boss 54 are screwed to the position where the end surface of the inner side of the second shaft section 522 is attached to the end surface of the outer side of the second boss 54.

A second shaft sleeve 55 is sleeved on the outer wall of the second boss 54; the second rotating shaft 2 passes through the inner hole of the second shaft sleeve 55, and the outer wall of the second shaft sleeve 55 is rotatably connected with the second air radial bearing 21; the second shaft sleeve 55 is provided with a second shaft sleeve boss 551, and the thrust disc 22 and the heat dissipation impeller 23 are sleeved on the outer wall of the second shaft sleeve boss 551; the second lock nut 24 is screwed with the external thread of the fourth shaft section 524; when the second locking nut 24 is locked, the second shaft sleeve 55 is axially locked on the second rotating shaft 2, and the thrust disc 22 and the heat dissipation impeller 23 are axially locked on the second shaft sleeve 55. The outer surface of the second sleeve 55 is provided with a PVD coating. When the air suspension blower is just started, the second shaft sleeve 55 is not supported and suspended by the second air radial bearing 21, and dry friction is generated between the outer wall of the second shaft sleeve 55 and the second air radial bearing 21; and because the surface of the second shaft sleeve 55 is smooth and has a PVD coating, the friction coefficient is low, the hardness is high, and the contact friction times can reach more than 40000 times. When the contact friction reaches the upper limit and is damaged, only the worn second shaft sleeve 55 needs to be replaced without replacing the second rotating shaft 2, thereby increasing the service life of the second rotating shaft 2.

The third rotating shaft 3 comprises a fifth shaft segment 531, a sixth shaft segment 532, a seventh shaft segment 533 and an eighth shaft segment 534; the outer walls of the fifth shaft section 531 and the eighth shaft section 534 are both provided with external threads, and a third boss 56 is arranged at one end of the motor shaft 1, which is positioned at the third rotating shaft 3; the third boss 56 is provided with an inner hole with an internal thread, and the external thread of the five-axis section 531 and the internal thread of the inner hole of the third boss 56 are screwed to the joint position of the end surface of the inner side of the sixth axis section 532 and the end surface of the outer side of the third boss 56.

A third shaft sleeve 57 is sleeved on the outer wall of the third boss 56; the third rotating shaft 3 passes through an inner hole of the third shaft sleeve 57, and the outer wall of the third shaft sleeve 57 is rotatably connected with the third air radial bearing 31; the third shaft sleeve 57 is provided with a third shaft sleeve boss 571, the blower impeller 32 is sleeved on the outer wall of the third shaft sleeve boss 571, and the third locking nut 33 is screwed with the external thread of the eighth shaft section 534; when the third lock nut 33 is locked, the third shaft housing 57 is axially locked to the third shaft 3, and the blower impeller 32 is axially locked to the third shaft housing 57. The outer surface of the third sleeve 57 is provided with a PVD coating. When the air suspension blower is just started, the third shaft sleeve 57 is not supported and suspended by the third air radial bearing 31, and dry friction is generated between the outer wall of the third shaft sleeve 57 and the third air radial bearing 31; and because the surface of the third shaft sleeve 57 is smooth and has a PVD coating, the friction coefficient is low, the hardness is high, and the contact friction times can reach more than 40000 times. When the contact friction reaches the upper limit and is damaged, only the worn third shaft sleeve 57 needs to be replaced, and the third rotating shaft 3 does not need to be replaced, so that the service life of the third rotating shaft 3 is prolonged.

The second shaft sleeve 55 and the third shaft sleeve 57 are axially and symmetrically distributed along the mass center of the motor shaft 1, so that the second shaft sleeve 55 and the third shaft sleeve 57 are ensured not to influence the mass center position of the motor shaft system. The second air radial bearing 21 and the third air radial bearing 31 are fixed to the first end cap 15 and the second end cap 16, respectively.

As shown in fig. 1, the second end cover 16 is provided with a first thrust disk groove 161 and a second thrust disk groove 162, and the first thrust disk groove 161 and the second thrust disk groove 162 are oppositely arranged at two ends of the thrust disk 22; the axial air bearing 17 is provided with an axial direction stopper portion 171 for restricting the axial direction position of the thrust disk 22, and the two axial direction stopper portions 171 are fixed to the first thrust disk groove 161 and the second thrust disk groove 162, respectively. Thereby ensuring that the axial direction restricting portions 171 at both ends of the thrust disc 22 control the axial direction position of the motor shaft 1 by controlling the axial direction position of the thrust disc 22.