CN103095084B - A kind of oil-immersed type high-specific-power permanent-magnet brushless DC electric machine - Google Patents
A kind of oil-immersed type high-specific-power permanent-magnet brushless DC electric machine Download PDFInfo
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- CN103095084B CN103095084B CN201110332631.XA CN201110332631A CN103095084B CN 103095084 B CN103095084 B CN 103095084B CN 201110332631 A CN201110332631 A CN 201110332631A CN 103095084 B CN103095084 B CN 103095084B
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Abstract
The present invention relates to a kind of permanent-magnet brushless DC electric machine, be specifically related to a kind of oil-immersed type high-specific-power permanent-magnet brushless DC electric machine.It comprises rotor, be sleeved on epitrochanterian stator, be packaged in the housing outside stator, end cap, stator exterior is the cylinder being provided with radial lugs vertically in the middle of this stator cylindrical, this radial lugs circumference leaves several axial notches, and stator and housing interference fit are also fixing, and stators and rotators leaves gap suit and coordinates; Shell one end is open end, the other end is the tubular structure having open-work end, the boss along housing axis is had on the downside of this housing, this boss is being provided with close to housing open one end place the passage be connected with shell inner surface, this passage refers in the middle of described boss cross section from shell inner surface extension, in boss, be provided with asphalt channel to the direction away from housing open end from this middle, boss cross section, this asphalt channel extends housing always.Structure of the present invention is simple, and reliable, specific power is high.
Description
Technical field
The present invention relates to a kind of permanent-magnet brushless DC electric machine, be specifically related to a kind of oil-immersed type high-specific-power permanent-magnet brushless DC electric machine.
Background technology
Permanent-magnet brushless DC electric machine be a kind ofly adopt permanent magnet excitation, electromechanical energy conversion device that electronic commutation substitutes mechanical commutation.Therefore, permanent-magnet brushless DC electric machine not only has the good control characteristic of general DC motor, also there is the series of advantages such as structure is simple, volume is little, lightweight, non-commutation spark, reliability are high, long working life, adaptation hypobaric ability are strong, be widely used in industrial circle.
In conventional electric hydraulic servo-machine construction system, high-speed electric expreess locomotive is adopted to drive hydraulic pump to provide hydraulic energy source.This kind of structural requirement oil pump must carry out rotary dynamic seal design, and motor internal can not enter hydraulic oil, therefore does not need to carry out Seal Design.Running up and under severe operational environment, requiring higher to the rotary dynamic seal of oil pump, and unfavorable to longer-term storage.In some industrial occasions, very strict to the weight of motor, volume requirement, and cancel oil pump movable sealing, motor internal enters hydraulic oil.Traditional shield electric machine adopts shield cover structure to allow motor internal to enter fluid or other liquid, this kind of structure increases motor gas-gap, cannot realize small size, high-specific-power requirement, generally only be only applicable to the running occasion being no more than 3000r/min, the requirement run up cannot be met.Visible, traditional product and shield electric machine technology all cannot meet the motor requirement of some field oil-immersed types, high-specific-power, small size, therefore, need to adopt new technology to solve.
Summary of the invention
The technical problem that will solve of the present invention is to provide a kind of oil-immersed type high-specific-power permanent-magnet brushless DC electric machine, and this electric machine structure is simple, and volume is little, lightweight, specific power is high, adapts to the requirement that hydraulic oil enters motor internal.
In order to solve the problems of the technologies described above, technical scheme of the present invention is,
A kind of oil-immersed type high-specific-power permanent-magnet brushless DC electric machine, comprises rotor, is sleeved on epitrochanterian stator, be packaged in the housing outside stator, end cap, it is characterized in that:
Described stator outer wall is provided with several axial notches, and stator is fixed in housing, and described stators and rotators leaves gap suit and coordinates;
Described housing is provided with asphalt channel, and this asphalt channel extends near the housing other end from shell one end always, is connected near this asphalt channel of housing other end place described with inner walls.
Described shell one end is open end, and the other end is the tubular structure having open-work end.
Described rotor comprises rotating shaft, and this rotating shaft runs through whole housing, and one end of this rotating shaft to be connected by clutch shaft bearing through housing open end and the end cap being fixed on this housing open end and extends outside described end cap; The other end and the housing of this rotating shaft are had open-work end and are connected by the second bearing and stretch out outside this housing, and this rotating shaft and described housing have between open-work end and leave gap.
Described rotor also comprises yoke, permanent magnet, protective sleeve, end plate; Described yoke and shaft set are fixed, and the axial length permanent magnet suit consistent with yoke is fixed in yoke, and be set with protective sleeve at permanent magnet outer surface, protective sleeve is fixed with the end plate being fixed on yoke two ends.
Described stator comprises stator core and stator winding, and described stator core is cross section is annular tubular structure, and this stator core circumferentially evenly offers several axially penetrating grooves, and described stator winding is embedded in each groove.
Described stator core adopts high-saturation magnetic induction soft magnetic material 1J22.
Described protective sleeve adopts nonmagnetic stainless steel to make, and its thickness is according to being more than or equal to 0.2mm.
Described housing exterior walls one sidepiece is provided with power supply base, and this power supply base is connected with stator winding by wire; The described rotating shaft part suit extended outside described end cap is connected with end cap outer rim described in rotor-position sensor and is fixed with rear end cap, in rotor-position sensor and rotating shaft are wrapped in by this rear end cap, rear end cap top is provided with signal plug, and this signal plug is connected with rotor-position sensor by wire.
Described power supply base and signal plug adopt glass frit seal type socket.
Beneficial effect of the present invention:
(1) structure is simple, and reliable, specific power is high.
(2) adapt to the requirement that hydraulic oil enters motor internal, cancel the rotary dynamic seal of motor load and hydraulic pump, increase substantially the reliability of electric-motor pump and adapt to long-term storage capability.
(3) stator adopts high temperature resistant encapsulation technology, and not needing additionally increases motor gas-gap, easily realizes higher specific power, reduces volume and weight.
(4) when High Rotation Speed, the frictional dissipation of hydraulic oil can effectively be reduced.
(5) stator outer surface design oil circuit, is conducive to the flowing of hydraulic oil, and can cools motor, improve motor temperature resistant capability.
(6) adopt glass frit seal type socket, can effectively prevent motor internal hydraulic oil from the leakage cable.
Accompanying drawing explanation
Fig. 1 is a kind of oil-immersed type high-specific-power of the present invention permanent-magnet brushless DC electric machine profile;
Fig. 2 is the middle A-A profile of a kind of oil-immersed type of the present invention high-specific-power permanent-magnet brushless DC electric machine profile;
Fig. 3 is the stator profile of a kind of oil-immersed type high-specific-power of the present invention permanent-magnet brushless DC electric machine;
Fig. 4 is B-B profile in the stator profile of a kind of oil-immersed type high-specific-power of the present invention permanent-magnet brushless DC electric machine;
Fig. 5 is graphics after the stator embedding of a kind of oil-immersed type high-specific-power of the present invention permanent-magnet brushless DC electric machine;
Fig. 6 is the rotor profiles figure of a kind of oil-immersed type high-specific-power of the present invention permanent-magnet brushless DC electric machine;
Fig. 7 is the C-C profile of the rotor profiles figure of a kind of oil-immersed type high-specific-power of the present invention permanent-magnet brushless DC electric machine.
In figure: 1-stator; 2-rotor; 3-housing; 4-end cap; 5-rear end cap; 6-power supply base; 7-signal plug; 8-rotor-position sensor; 9-first sealing ring; 10-screw plug; 11-asphalt channel; 12-oil groove; 13-return port; 14-second sealing ring; 15-location-plate; 1-1-stator core; 1-2-stator winding; 2-1-rotating shaft; 2-2-yoke; 2-3-permanent magnet; 2-4-protective sleeve; 2-5-end plate; 2-6-clutch shaft bearing, 2-7 second bearing.
Embodiment
Below in conjunction with accompanying drawing 1 to accompanying drawing 7 and embodiment, the present invention is described further.
A kind of oil-immersed type high-specific-power of the present invention brshless DC motor comprises rotor 2, be sleeved on epitrochanterian stator 1, be packaged in the housing 3 outside stator 1, end cap 4, described stator 1 outside is the cylinder being provided with radial lugs vertically in the middle of this stator cylindrical 1, this radial lugs circumference leaves several axial notches, define oil groove 12, stator 1 and housing 3 interference fit, and be fixed with trip bolt, described stator 1 and rotor 2 leave gap suit and coordinate.
Described housing 3 one end is open end, the other end is the tubular structure having open-work end, and this housing 3 lower wall is provided with the boss along housing 3 axis, this boss has open-work one end place at housing 3 and is provided with asphalt channel 11, this asphalt channel 11 is extended down near housing 3 open end always, at this near housing 3 open end place, described asphalt channel 11 is connected with housing 3 inner surface; Blocked by the outlet away from housing 3 open end of screw plug 10 by this asphalt channel 11, be provided with on the base of housing 3 one the return port 13 be communicated with this asphalt channel 11, this return port 13 is finally connected with external fuel tank; Described asphalt channel 11 and oil groove 12 form oil circuit, are beneficial to the flowing of hydraulic oil and the heat radiation to stator, and additionally can not increase gas length.
Described rotor 2 comprises rotating shaft 2-1, this rotating shaft 2-1 runs through whole housing 3, one end of this rotating shaft 2-1 is connected to and the end cap 4 be screwed at this housing 3 open end at the clutch shaft bearing 2-6 of this cover internal by bearing sleeve through housing 3 open end, and extend outside described end cap 4, be provided with the second sealing ring 14 between described end cap 4 and body, prevent hydraulic oil from externally leaking from motor internal; The other end and the housing 3 of this rotating shaft 2-1 are had circular through-hole end and to be connected at the second bearing 2-7 of this end inside of housing 3 by bearing sleeve and stretch out outside this housing 3.Described rotor 2 also comprises yoke 2-2, permanent magnet 2-3, protective sleeve 2-4, end plate 2-5; Described yoke 2-2 is set with fixing by rolling or flat key and rotating shaft 2-1, yoke 2-2 circumference is evenly provided with four axial draw-in grooves, this axial draw-in groove is provided with the location-plate 15 that four axial lengths are consistent with yoke 2-2, the permanent magnet 2-3 that four axial lengths are consistent with yoke 2-2 is provided with between each location-plate 15, should be fixed on yoke 2-2 by high-temperature plastic by permanent magnet 2-3, be set with protective sleeve 2-4 at permanent magnet 2-3 outer surface, during to prevent High Rotation Speed, permanent magnet 2-3 damages by centrifugal action; Protective sleeve 2-4 adopts the mode of laser welding to be fixed with the end plate 2-5 being fixed on yoke two ends.In order to reduce the viscous friction moment of hydraulic oil, ensure higher roughness at the outer surface of rotor 2 by the mode of machining.Protective sleeve 2-4 adopts nonmagnetic stainless steel to make, and its thickness is determined according to the size of rotor 2, rotating speed, and its size can be 0.2mm, 0.3mm, 0.4mm, 0.5mm, here preferred 0.3mm.
Described stator 1 comprises stator core 1-1 and stator winding 1-2, described stator core 1-1 is cross section is annular tubular structure, this stator core 1-1 circumferentially offers several axially penetrating grooves, described stator winding 1-2 is embedded in each groove, high-temperature plastic is adopted to carry out overall vacuum embedding process to stator winding and nail iron core, without the need to dipping lacquer, stator 1 inner circle is smooth, cylindrical peripheral surface, to reduce the frictional dissipation of fluid; In order to reduced volume, described stator core 1-1 adopts high-saturation magnetic induction soft magnetic material 1J22.
Outside described housing 3 side, circular top part has cylindrical flange, and this cylindrical flange is fixed with power supply base 6 by screw, and this power supply base 6 is connected with stator winding 1-2 by wire; The part suit that described rotating shaft 2-1 extends outside described end cap 4 is connected with rotor-position sensor 8, and this branch's axle head of described rotating shaft 2-1 and rotor-position sensor 8 is fixed by large screw; Described end cap 4 outer rim is fixed with rear end cap 5 by screw, and between end cap 4 and rear end cap 5, be provided with the first sealing ring 9, prevents hydraulic oil from externally leaking from motor internal; In rotor-position sensor 8 and rotating shaft 2-1 are wrapped in by this rear end cap 5, rear end cap 5 top is also provided with cylindrical flange, and this cylindrical flange is fixed with signal plug 7 by screw, and this signal plug 7 is connected with rotor-position sensor 8 by wire; Described power supply base 6 and signal plug 7 adopt glass frit seal type socket.
During work, peripheral driver is according to the measuring-signal of rotor-position sensor 8, power to stator winding 2-2 through power supply base 6 according to certain rules, according to the operation principle of permanent-magnet brushless DC electric machine, under the interaction of stator 1 and rotor 2, rotor 2 is rotated, and by rotating shaft 2-1 output mechanical energy.Hydraulic oil flows into motor internal by rotating shaft 2-1 axle stretch end under pressure, and flow to other side through the oil circuit of the gap between stator 1 and rotor 2 and asphalt channel 11 and oil groove 12 formation from the side of motor internal, finally flow to external fuel tank from housing 3 return port 13, running of hydraulic power oil signal is shown in Fig. 1 shown in arrow, and hydraulic oil lubricates bearing and motor cools.
A kind of oil-immersed type high-specific-power permanent-magnet brushless DC electric machine scheme given above, user according to the demand in concrete mounting interface and space, according to practical service environment, can carry out concrete design to each several part size, parameter.
Claims (8)
1. an oil-immersed type high-specific-power permanent-magnet brushless DC electric machine, comprises rotor (2), is sleeved on epitrochanterian stator (1), is packaged in stator (1) housing outward (3), and end cap (4), is characterized in that:
Described stator (1) outer wall is provided with several axial notches, and axial notch forms oil groove (12), and stator (1) is fixed in housing (3), and described stator (1) and rotor (2) leave gap suit and coordinate;
Described housing (3) one end is open end, and the other end is the tubular structure having open-work end;
Described housing (3) is provided with asphalt channel (11), this asphalt channel (11) extends to open end near housing (3) from the open-work end that has of housing (3) always, at close described housing (3) open end place, this asphalt channel (11) is connected with housing (3) inwall, blocked by the outlet away from housing (3) open end of screw plug (10) by this asphalt channel (11), be provided with on the base of housing (3) one the return port (13) be communicated with this asphalt channel (11), this return port (13) is finally connected with external fuel tank;
Described asphalt channel (11) and oil groove (12) form oil circuit.
2. according to a kind of oil-immersed type high-specific-power permanent-magnet brushless DC electric machine according to claim 1, it is characterized in that: described rotor (2) comprises rotating shaft (2-1), this rotating shaft (2-1) runs through whole housing (3), and one end of this rotating shaft (2-1) to be connected by clutch shaft bearing (2-6) through housing (3) open end and the end cap (4) being fixed on this housing (3) open end and extends described end cap (4) outward; The other end and the housing (3) of this rotating shaft (2-1) are had open-work end and are connected by the second bearing (2-7) and stretch out this housing (3) outward, and this rotating shaft (2-1) and described housing (3) have between open-work end and leave gap.
3., according to a kind of oil-immersed type high-specific-power permanent-magnet brushless DC electric machine according to claim 2, it is characterized in that: described rotor (2) also comprises yoke (2-2), permanent magnet (2-3), protective sleeve (2-4), end plate (2-5); Described yoke (2-2) and rotating shaft (2-1) are set with fixing; the axial length permanent magnet (2-3) consistent with yoke (2-2) is set with and is fixed in yoke (2-2); be set with protective sleeve (2-4) at permanent magnet (2-3) outer surface, protective sleeve (2-4) is fixed with the end plate (2-5) being fixed on yoke two ends.
4. according to a kind of oil-immersed type high-specific-power permanent-magnet brushless DC electric machine according to claim 3, it is characterized in that: described stator (1) comprises stator core (1-1) and stator winding (1-2), described stator core (1-1) for cross section be annular tubular structure, this stator core (1-1) circumferentially evenly offers several axially penetrating grooves, and described stator winding (1-2) is embedded in each groove.
5., according to a kind of oil-immersed type high-specific-power permanent-magnet brushless DC electric machine according to claim 4, it is characterized in that: described stator core (1-1) adopts high-saturation magnetic induction soft magnetic material 1J22.
6., according to a kind of oil-immersed type high-specific-power permanent-magnet brushless DC electric machine according to claim 3, it is characterized in that: described protective sleeve (2-4) adopts nonmagnetic stainless steel to make, and its thickness is more than or equal to 0.2mm.
7. according to a kind of oil-immersed type high-specific-power permanent-magnet brushless DC electric machine described in claim 4 or 5, it is characterized in that: described housing (3) outer wall one side roof part is provided with power supply base (6), and this power supply base (6) is connected with stator winding (1-2) by wire; Described rotating shaft (2-1) is extended described end cap (4) part suit outward and is connected with rotor-position sensor (8); Described end cap (4) outer rim is fixed with rear end cap (5), in rotor-position sensor (8) and rotating shaft (2-1) are wrapped in by this rear end cap (5), rear end cap (5) top is provided with signal plug (7), and this signal plug (7) is connected with rotor-position sensor (8) by wire.
8. according to a kind of oil-immersed type high-specific-power permanent-magnet brushless DC electric machine according to claim 7, it is characterized in that: described power supply base (6) and signal plug (7) adopt glass frit seal type socket.
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| CN201110332631.XA CN103095084B (en) | 2011-10-27 | 2011-10-27 | A kind of oil-immersed type high-specific-power permanent-magnet brushless DC electric machine |
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| CN201110332631.XA CN103095084B (en) | 2011-10-27 | 2011-10-27 | A kind of oil-immersed type high-specific-power permanent-magnet brushless DC electric machine |
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| CN103095084B true CN103095084B (en) | 2015-09-30 |
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| JP3661529B2 (en) * | 1999-11-17 | 2005-06-15 | 日産自動車株式会社 | Motor cooling device |
| CN2428911Y (en) * | 2000-06-12 | 2001-05-02 | 朱向东 | Long-service-life multi-model type permanent magnet brushless servo electric motor |
| CN1125524C (en) * | 2001-01-18 | 2003-10-22 | 合肥工业大学 | Plastic capsulation submerged motor and its capsulation material and technology |
| EP1241773B1 (en) * | 2001-03-14 | 2012-09-12 | Nissan Motor Co., Ltd. | Rotating electrical machine with air-gap sleeve |
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| CN1889334A (en) * | 2005-06-29 | 2007-01-03 | 中国科学院电工研究所 | External water channel evaporative cooling horizontal motor |
| CN100448141C (en) * | 2006-10-16 | 2008-12-31 | 中山大学 | Alternating current permanent-magnet water-submersible electric machine |
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