Electrical generator or motor structure – Dynamoelectric – Rotary
Patent
1986-06-30
1987-09-01
Salce, Patrick R.
Electrical generator or motor structure
Dynamoelectric
Rotary
310 60A, 310259, H02K 9193
Patent
active
046911316
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to a liquid-cooled AC motor comprising a stator having a laminated core having coils inserted therein and provided with passages for passing a cooling liquid therethrough to cool the stator directly with the cooling liquid and, more particularly, to an improved liquid-cooled motor capable of preventing thermal distortion of the stator.
BACKGROUND ART
The stator of an AC motor comprises a laminated core mounted with coils, and heat is generated in the stator due to iron loss and copper loss, which has a serious adverse influence on the useful life and performance of the motor. To obviate this adverse influence of the heat generated in the stator on the useful life and performance of the AC motor, methods of removing heat from the stator by circulating cooling air through the laminated core (for example, U.S. Pat. No. 4,534,686) and methods of removing heat from the stator by circulating a cooling liquid capable of efficient heat removal have been provided or proposed.
A liquid-cooled motor in which a cooling liquid is circulated through the laminated core of the stator has an advantage over an air-cooled motor in that the cooling medium is capable of a high heat removing efficiency, and thus the cooling medium cools the motor at high efficiency. Nevertheless, the liquid-cooled motor has a problem in that thermal distortion of the liquid-cooled motor occurs when the laminated core is subjected to the cooling effect of the cooling liquid during the operation of the liquid-cooled motor if the heat distribution in the laminated core and the peripheral parts is not uniform, and accordingly, the rotor will fail to rotate smoothly, and because of the resulting unsteady rotation, the rotor shaft is unable to apply a fixed torque to the driven object associated with the liquid-cooled motor.
DISCLOSURE OF THE INVENTION
Accordingly, it is an object of the present invention to provide a liquid-cooled motor provided with means for obviating the above-mentioned thermal distortion.
In view of the object of the invention, the present invention employs a configuration capable of a symmetrical distribution of the cooling effect in the laminated core with respect to the center axis thereof. That is, according to the present invention, a liquid-cooled motor having cooling liquid passages formed in the laminated core of the stator thereof, for directly cooling the laminated core with a cooling liquid, is characterized in that a plurality of the cooling liquid passages extend axially and are distributed, as viewed in cross section perpendicular to the axis, symmetrically with respect to the center axis in the laminated core of the stator having the shape of a hollow tube and surrounding the cylindrical rotor with a gap therebetween. Such an arrangement of the cooling liquid passages develops a cooling effect that will constantly maintain a uniform distribution of heat in the laminated core and the peripheral parts to obviate thermal distortion of the laminated core.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view showing a cross section perpendicular to the axis of a liquid-cooled motor having cooling liquid passages, embodying the present invention; and
FIG. 2 is a schematic illustration showing a cooling liquid piping system of the liquid-cooled motor of FIG. 1.
FIG. 3 is a partial cross-section through the motor stator showing in greater detail the lamination structure.
BEST MODE FOR CARRYING OUT THE INVENTION
Referring to FIG. 1, a liquid-cooled motor 10 has a rotor 14 rotatably supported by a rotor shaft 12. The rotor 14 is a cylindrical body extending coaxially with the rotor shaft 12. The liquid-cooled motor 10 has a stator 16 surrounding the rotor 14 with a gap G therebetween. The stator 16 is a hollow tubular body receiving the rotor 14 therein. The stator 16 comprises a laminated core 18 and known stator coils, not shown, inserted in radial slots formed in the inner circumference of the laminated core 18. When an exciting current is supplied to the
REFERENCES:
patent: 1451577 (1923-04-01), Jantzen
patent: 1959527 (1934-05-01), Ehrmann
patent: 3322985 (1967-05-01), Azbukin et al.
patent: 4085347 (1978-04-01), Lichius
patent: 4323803 (1982-04-01), Danko et al.
patent: 4406959 (1983-09-01), Harano et al.
Fanuc Ltd.
Rebsch D. L.
Salce Patrick R.
LandOfFree
Stator laminate impregnation in a liquid-cooled motor does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Stator laminate impregnation in a liquid-cooled motor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Stator laminate impregnation in a liquid-cooled motor will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1266811