CN216549148U - Two-in-one permanent magnet synchronous traction machine special for elevator - Google Patents
Two-in-one permanent magnet synchronous traction machine special for elevator Download PDFInfo
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- CN216549148U CN216549148U CN202122900382.1U CN202122900382U CN216549148U CN 216549148 U CN216549148 U CN 216549148U CN 202122900382 U CN202122900382 U CN 202122900382U CN 216549148 U CN216549148 U CN 216549148U
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B50/00—Energy efficient technologies in elevators, escalators and moving walkways, e.g. energy saving or recuperation technologies
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Abstract
The utility model discloses a special two-in-one permanent magnet synchronous traction machine for an elevator, which solves the problem that the traditional elevator traction machine in the prior art is of a structure of a motor and a reduction gearbox and has larger volume. A planetary gear speed reducing mechanism is added, so that the rotating speed of the motor is increased; the inner space of the traction sheave is fully utilized, the planetary gear speed reducing mechanism and the motor are arranged in the traction sheave, the space is saved, the outer diameter of the motor can be reduced, and the efficiency and the power density can be increased.
Description
Technical Field
The utility model relates to the technical field of elevator equipment, in particular to a special two-in-one permanent magnet synchronous traction machine for an elevator.
Background
The efficiency of the permanent magnet synchronous traction machine applied to the elevator at present is about 87%, because the rotating speed of the motor is low, the efficiency is difficult to be improved in the design of the motor body, and more material cost needs to be invested if higher efficiency is needed. The high-speed motor can obtain higher efficiency relatively easily, and the efficiency can reach 97% when the rotating speed is about 2000 revolutions by taking a new energy automobile motor as an example. The power density is also higher. Therefore, the high-speed motor has the characteristics of high efficiency, high power density and small volume.
Meanwhile, elevators without machine rooms and elevators with small machine rooms are increasingly favored by customers, which requires that the size of the permanent magnet synchronous gearless motor is smaller and smaller, and along with this, miniaturized and ultrathin tractors such as steel belt tractors and axial magnetic field tractors have appeared. The high-speed motor just meets the market demand of small volume, so the advantage of the high-speed motor is obvious, and the key problem is how to configure a speed reducing mechanism to enable the high-speed motor to be applied to the field of elevators.
The early tractor is a structure of a motor and a reduction gearbox. For example, the chinese patent office 2016, 8, 31 discloses a utility model entitled elevator traction machine, whose publication number is CN 205527226U. The utility model comprises a frame, a permanent magnet synchronous motor, a reduction gearbox, a traction sheave, a brake, an encoder, a main controller, a speed sensor, an alarm and a display, wherein the speed sensor is arranged at one side of an output shaft of the reduction gearbox, and the main controller is respectively connected with the speed sensor, the alarm and the display; the elevator tractor adopts the permanent magnet synchronous motor as the driving motor of the tractor, and has the characteristics of high power factor and high efficiency; the elevator tractor adopts the planetary gear reduction gearbox with small tooth difference, the efficiency of the reduction gearbox can reach more than 95 percent, and the reduction gearbox has compact structure and convenient processing; the utility model discloses an elevator hauler adopts the running speed of speed sensor real-time collection driving sheave, and when the running speed of driving sheave exceeded the predetermined range, controller accessible control alarm sent the police dispatch newspaper, has improved the security of elevator hauler. But the volume is larger and the structure is not compact enough.
SUMMERY OF THE UTILITY MODEL
The utility model aims to overcome the problem that the traditional elevator traction machine in the prior art is of a structure of a motor and a reduction gearbox and has larger volume, and provides a special two-in-one permanent magnet synchronous traction machine for an elevator.
In order to achieve the purpose, the utility model adopts the following technical scheme: the elevator traction system comprises a permanent magnet synchronous motor, a traction sheave and a set of planetary gear reduction mechanism, wherein the planetary gear reduction mechanism is installed inside the traction sheave, the permanent magnet synchronous motor is installed inside the planetary gear reduction mechanism, the planetary gear reduction mechanism comprises a planetary gear row, the planetary gear row is connected with the traction sheave, and the traction sheave is connected with an elevator car through a steel wire rope.
The power of the permanent magnet synchronous motor is transmitted to the traction sheave through the speed reduction of the planetary gear speed reducing mechanism, and the traction sheave drags the steel wire rope to drive the lift car to move up and down. The permanent magnet synchronous motor is arranged in the planetary gear speed reducing mechanism, the motor is not provided with a shell, the planetary gear speed reducing mechanism is arranged in the traction sheave, the internal space of the traction sheave is fully utilized, the appearance of the traction sheave is very simple, and the internal structure is very compact. And because the planetary gear speed reducing mechanism is added, the rotating speed of the motor is improved, the outer diameter of the motor can be reduced in design, and the efficiency and the power density can be increased. The efficiency of the motor body is more than 92%, the transmission efficiency of the planetary gear is close to 98%, and the overall efficiency is more than 90%.
Preferably, the permanent magnet synchronous motor comprises a main shaft, a stator assembly and a rotor assembly, the stator assembly is connected with a power supply of a frequency converter, the frequency converter is connected with a control system, the stator assembly is sleeved on the main shaft, and the rotor assembly is sleeved on the stator assembly. The permanent magnet synchronous motor adopts an outer rotor structure. The stator assembly is connected with a power supply of an external frequency converter, and converts electric energy into mechanical energy to provide power for the rotor assembly; the rotor assembly rotates by utilizing the power provided by the stator assembly and drives the planetary gear speed reducing mechanism to rotate. The control system controls the permanent magnet synchronous motor in real time through the frequency converter.
Preferably, the main shaft is a fixed non-rotating shaft, and the main shaft is further provided with an opening or a groove. The power line of the stator assembly is led out through the opening or the groove on the main shaft.
Preferably, the device further comprises a rotary encoder, and a power line of the rotary encoder is led out through an opening or a groove in the main shaft. The rotary encoder is preferably a rotary variable sensor, is used for detecting the rotating speed and the position of the rotor assembly, is a signal element with the output voltage changing along with the rotating angle of the rotor, and has strong adaptability, good reliability and low cost.
Preferably, the planetary gear train include sun gear, planet wheel and outer ring gear, the sun gear is connected with the rotor subassembly through interference connection plus location slightly or the structure of parallel key, the sun gear still is connected with the planet wheel, the planet wheel passes through the gear carrier to be fixed on the main shaft, outer ring gear is connected with the planet wheel, outer ring gear is connected with the driving sheave through interference connection plus location round pin's structure. The interference connection adds the structure of locating pin or flat key, guarantees to transmit moment between external rotor and the sun gear to can not produce relative displacement. After the permanent magnet synchronous motor is electrified, a rotor in the rotor assembly can drive the sun gear to rotate when rotating, the sun gear can drive the planet gear to rotate when rotating, and the planet gear transmits power to the outer gear ring to drive the outer gear ring to rotate. The outer gear ring receives the rotation power of the planet wheel and transmits the rotation power of the planet wheel to the traction wheel, so that the rotation of the permanent magnet synchronous motor is transmitted to the traction wheel after being reduced by the planet gear reduction mechanism. The outer gear ring of the planet gear and the traction sheave are in interference connection and are provided with the positioning pin, the structure is more compact, and the internal space of the traction sheave is fully utilized. Meanwhile, the torque can be transmitted between the outer gear ring and the traction sheave, and relative displacement cannot be generated. The traction sheave serves as a part of the housing, thereby eliminating the housing structure of the conventional transmission and the housing structure of the conventional motor.
Preferably, the elevator further comprises a magnetic grating ruler, and the magnetic grating ruler is installed in the elevator shaft. The magnetic grid ruler is used for detecting the position of the elevator car in real time. The magnetic grid ruler adopts differential or single-ended pulse output signals, so that the product is small and exquisite in appearance and convenient to install in a small space; the elevator shaft is resistant to complex working environments such as oil stain, liquid, dust and vibration and is suitable for elevator shafts. And meanwhile, the device has high reliability and high precision.
Preferably, the traction device further comprises stressed end covers, and the stressed end covers are arranged on two sides of the traction sheave. The design of the utility model is that the traction sheave is not provided with a brake disc, and the brake surface is the outer edge surface of the stressed end cover. The advantage is that the structure is simpler, has utilized the terminal surface of current part, does not need to design a brake lining alone. Meanwhile, the stressed end covers are arranged on two sides of the traction sheave and form an internal space with the traction sheave, and the permanent magnet synchronous motor and the planetary gear speed reducing mechanism are arranged in the internal space, so that the space is saved, and the structure is more compact.
Preferably, the bearing further comprises a first bearing, wherein the first bearing is sleeved on the main shaft and is positioned between the stressed end cover and the main shaft.
Preferably, the device further comprises a brake, and the brake is connected with the stressed end cover. The brake acts on the stress end cover, so that the elevator in operation automatically stops the elevator car when the power supply is cut off, and simultaneously, when the elevator stops operation, the brake can ensure that the elevator car keeps still and the position of the elevator car is unchanged under the condition of 125 percent of rated load.
Preferably, the rotary encoder is an electromagnetic induction rotary transducer. The rotary variable sensor has low price, and can be matched with a magnetic grid ruler arranged in a well, so that high-precision motor control and car leveling control can be realized.
Therefore, the utility model has the following beneficial effects: 1. a planetary gear speed reducing mechanism is added, so that the rotating speed of the permanent magnet synchronous motor is increased; 2. the outer diameter of the permanent magnet synchronous motor can be reduced, and the efficiency and the power density can be increased; 3. the motor, the planetary gear and the traction sheave are organically combined together through mechanical design, so that the rotating speed of the motor is improved, and the structure of the permanent magnet synchronous traction machine is more compact; 4. the internal space of the traction sheave is fully utilized, the planetary gear speed reducing mechanism and the permanent magnet synchronous motor are arranged in the traction sheave, so that the purpose of saving space can be achieved, and the axial size of the traction machine is shortened, so that the traction machine has more advantages in the application of a machine room-less elevator; 5. the traction sheave is used as a part of the shell, and the shell of the permanent magnet synchronous motor and the shell of the speed reducer are cancelled, so that the mechanism of the two-in-one traction machine is simpler and more compact; 6. the rotary variable sensor with low price is adopted, and the magnetic grid ruler arranged in the shaft is matched, so that high-precision motor control and car leveling control are realized through signal fitting of the two speed position sensors.
Drawings
FIG. 1 is a schematic diagram of an embodiment of the present invention;
FIG. 2 is a schematic diagram of an embodiment of the present invention;
FIG. 3 is another schematic structural view of the present invention;
in the figure: 1. a main shaft; 2. a first bearing; 3. a stressed end cap; 4. a planetary gear row; 4-1, sun gear; 4-2, planet wheels; 4-3, an outer gear ring; 5. a traction sheave; 6. a rotor assembly; 7. a stator assembly; 8. a rotary encoder; 9. a power line; 10. a control system; 11. a frequency converter; 12. a second bearing; 13. a third bearing; 14. a magnetic grid ruler; 15. a car; 16. a permanent magnet synchronous motor; 17. a casing.
Detailed Description
The utility model is described in further detail below with reference to the following detailed description and accompanying drawings:
the present embodiment is a two-in-one permanent magnet synchronous traction machine dedicated for elevator, the structure diagram of which is shown in fig. 1, and the two-in-one permanent magnet synchronous traction machine includes:
the permanent magnet synchronous motor, the rotary encoder 8, the brake, the traction sheave 5 and a set of planetary gear reduction mechanism, the traction sheave does not have a brake disc, the brake surface is the outer edge surface of the end cover, the structure is simpler, the end surface of the existing component is utilized, and a brake surface does not need to be designed independently. The outer side of the traction sheave is also provided with a stressed end cover 3, the stressed end cover and the traction sheave form an internal space, and the planetary gear speed reducing mechanism is arranged in the internal space; the permanent magnet synchronous motor is arranged inside the planetary gear speed reducing mechanism, so that the space is saved, and the structure is more compact. Meanwhile, the permanent magnet synchronous motor is not provided with a shell, so that the space is further saved. The permanent magnet synchronous motor is connected with the planetary gear speed reducing mechanism, the planetary gear speed reducing mechanism is connected with the traction sheave, the power of the permanent magnet synchronous motor is transmitted to the traction sheave through the speed reduction of the planetary gear, and the traction sheave drags the steel wire rope to drive the lift car to move up and down. The brake acts on the stress end cover to keep the elevator car static and unchanged in position when the elevator stops running.
The permanent magnet synchronous motor comprises a main shaft 1, a stator assembly 6 and a rotor assembly 7, an outer rotor structure is adopted, the stator assembly is sleeved on the main shaft, and an air gap is formed between the rotor assembly and the stator assembly. The main shaft is a main stressed part and is a fixed non-rotating shaft, a hole or a groove is formed in the main shaft and used for leading out a power line 9 of the rotary encoder, a power line of the stator assembly is also led out through the main shaft and is externally connected with a power supply of the frequency converter 11. The main shaft is further sleeved with a first bearing 2, and the first bearing is located between the stressed end cover and the main shaft. The power cord of stator module is connected with the power of external converter, turns into mechanical energy with the electric energy, provides power for the rotor subassembly. The rotor assembly comprises a permanent magnet, a rotor magnetic yoke and the like, is driven to rotate by utilizing a rotating magnetic field generated by the stator assembly, and transmits torque to the planetary gear speed reducing mechanism.
The rotary encoder is a rotary variable sensor, is arranged on a rotor of the rotor assembly and is used for feeding back speed and position signals of the rotor.
The planetary gear speed reducing mechanism comprises a planetary gear row 4, the planetary gear row comprises a planetary gear 4-2, a sun gear 4-1 and an outer gear ring 4-3, the sun gear is connected with a rotor assembly, the sun gear is connected with the planetary gear, the planetary gear is connected with the outer gear ring, the outer gear ring is connected with a traction wheel, the planetary gear is fixed on a main shaft through a planetary carrier, the planetary gear can rotate, the planetary carrier cannot rotate, and the planetary gear can rotate but cannot revolve.
After the permanent magnet synchronous motor is electrified, the rotor of the rotor assembly can drive the sun gear of the planetary gear speed reducing mechanism to rotate when rotating, and the encoder is installed on the rotor and used for feeding back the speed and position signals of the rotor. The planet wheel is fixed on the main shaft through a gear carrier, and the sun wheel can drive the planet wheel to rotate when rotating and transmit the motion to the outer gear ring. The outer gear ring is connected with the traction sheave, so that the rotation of the permanent magnet synchronous motor is transmitted to the traction sheave after being reduced by the planetary gear reduction mechanism. The two sides of the traction sheave are provided with stressed end covers, and bearings are arranged in the stressed end covers. The stressed end cover can synchronously rotate along with the traction sheave. The outer side of the stressed end cover is processed and then used as a braking friction surface, and the brake is acted on a traction wheel on the stressed end cover and is provided with a rope groove which can drag a steel wire rope to drive the lift car to move up and down.
As shown in fig. 2, a magnetic scale 14 is installed in the hoistway, detects the position and speed of the car 15, and transmits the detected information to the control system 10, while the control system also receives speed and position signals of the motor rotor assembly transmitted by a rotary encoder installed on the permanent magnet synchronous motor. And the control system compares and fits the two groups of signals and controls the permanent magnet synchronous motor to rotate through the frequency converter.
Another structural schematic diagram of the present invention is shown in fig. 3, and the housing 17 is the main stressed component of the present invention, and the present invention can be installed by fixing the housing on the guide rail or the bearing beam.
The stator assembly of the permanent magnet synchronous motor comprises a coil, a silicon steel sheet and the like and is fixed on the shell, a power line of the stator assembly penetrates through the stress end cover and is connected into an external frequency converter, and a rotational magnetic field can be generated after the stator assembly is electrified to drive the rotor assembly to rotate. The rotor assembly comprises a permanent magnet and a rotor magnet yoke, the rotor assembly and a sun gear of the planetary gear speed reducing mechanism are in interference connection with each other and are provided with a positioning pin or a flat key, so that torque can be transmitted between the outer rotor and the sun gear, and relative displacement cannot be generated, so that the torque can be transmitted to the planetary gear speed reducing mechanism. Two second bearings 13 are arranged in the rotor, and the inner rings of the second bearings are arranged on the stress end covers.
The planet carrier of the planet gear is fixed on the machine shell, the planet gear is allowed to rotate but not revolve, and the outer gear ring is rigidly connected with the traction wheel. The outer gear ring of the planet gear and the traction sheave are in interference connection and are provided with the positioning pins, so that torque can be transmitted between the outer gear ring and the traction sheave, and relative displacement cannot be generated. The output torque of the rotor assembly is transmitted to the traction sheave through the planetary gear row.
The traction sheave is provided with a rope groove which can drag a steel wire rope to drive the lift car to move up and down. And a third bearing 14 is arranged in the stress end cover, and the inner ring of the third bearing is arranged on the stress end cover.
The rotary encoder is installed on the rotor assembly and feeds speed and position signals of the rotor assembly back to the control system, so that the control system can control the permanent magnet synchronous motor in real time.
The permanent magnet synchronous motor, the planetary gear speed reducing mechanism and the traction wheel are combined together through mechanical design, the planetary gear and the permanent magnet synchronous motor are arranged in the inner space of the traction wheel, the space is saved, and the axial size of the traction machine is shortened, so that the traction machine has more advantages in the application of a machine room-less elevator. Meanwhile, because a planetary gear speed reducing mechanism is added, the rotating speed of the permanent magnet synchronous motor is improved, the outer diameter of the permanent magnet synchronous motor can be reduced in design, and the efficiency and the power density can be increased. The efficiency of the permanent magnet synchronous motor body is above 92%, the transmission efficiency of the planetary gear is close to 98%, and the overall efficiency is above 90%.
The above-described embodiments are only preferred embodiments of the present invention, and are not intended to limit the present invention in any way, and other variations and modifications may be made without departing from the spirit of the utility model as set forth in the claims.
Claims (8)
1. The two-in-one permanent magnet synchronous traction machine special for the elevator is characterized by comprising a permanent magnet synchronous motor, a traction sheave and a set of planetary gear reduction mechanism, wherein the planetary gear reduction mechanism is installed inside the traction sheave, the permanent magnet synchronous motor is installed inside the planetary gear reduction mechanism, the planetary gear reduction mechanism comprises a planetary gear row, the planetary gear row is connected with the traction sheave, a rope groove is formed in the traction sheave, and the traction sheave is connected with an elevator car through a steel wire rope.
2. The two-in-one permanent magnet synchronous traction machine special for the elevator according to claim 1, wherein the permanent magnet synchronous motor comprises a main shaft, a stator assembly and a rotor assembly, a power line of the stator assembly is externally connected with a frequency converter, the frequency converter is connected with a control system, the stator assembly is sleeved on the main shaft, and the rotor assembly is sleeved on the stator assembly.
3. The two-in-one permanent magnet synchronous traction machine special for the elevator as claimed in claim 2, wherein the main shaft is a fixed non-rotating shaft, and the main shaft is further provided with an opening or a groove.
4. The special two-in-one permanent magnet synchronous traction machine for the elevator as claimed in claim 3, further comprising a rotary encoder, wherein a power cord of the rotary encoder is led out through a hole or a groove on the main shaft.
5. The two-in-one permanent magnet synchronous traction machine special for the elevator as claimed in claim 2, wherein the planetary gear train comprises a sun gear, a planet gear and an outer ring gear, the sun gear is connected with the rotor assembly through a structure of interference connection plus a positioning pin or a flat key, the sun gear is further connected with the planet gear, the planet gear is fixed on the main shaft through a gear carrier, the outer ring gear is connected with the planet gear, and the outer ring gear is connected with the traction wheel through a structure of interference connection plus a positioning pin.
6. The special two-in-one permanent magnet synchronous traction machine for the elevator as claimed in claim 1 or 2, further comprising a magnetic scale, wherein the magnetic scale is installed in the elevator shaft.
7. The two-in-one permanent magnet synchronous traction machine special for the elevator according to claim 1 or 2, further comprising stressed end covers, wherein the stressed end covers are installed on two sides of the traction sheave.
8. The two-in-one permanent magnet synchronous traction machine special for the elevator according to claim 1, further comprising a brake, wherein the brake acts on the force bearing end cover.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122900382.1U CN216549148U (en) | 2021-11-24 | 2021-11-24 | Two-in-one permanent magnet synchronous traction machine special for elevator |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202122900382.1U CN216549148U (en) | 2021-11-24 | 2021-11-24 | Two-in-one permanent magnet synchronous traction machine special for elevator |
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| CN216549148U true CN216549148U (en) | 2022-05-17 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115296482A (en) * | 2022-09-29 | 2022-11-04 | 深圳小象电动科技有限公司 | Hub motor with axial magnetic flux built-in planetary reducer |
-
2021
- 2021-11-24 CN CN202122900382.1U patent/CN216549148U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115296482A (en) * | 2022-09-29 | 2022-11-04 | 深圳小象电动科技有限公司 | Hub motor with axial magnetic flux built-in planetary reducer |
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