JP6376896B2 - Generator cooling structure - Google Patents

Description

  The present invention relates to a generator cooling structure, and more particularly to a generator cooling structure for cooling a rotor of a brushless synchronous generator.

  The synchronous generator is provided with a rotor that rotates integrally with the shaft and a stator disposed on the outer periphery of the rotor inside the casing, and supplies a DC field current to the field winding of the rotor. By rotating the rotor while rotating, an AC voltage is generated in the armature winding of the stator. Further, the shaft is provided with a cooling fan for circulating cooling air for suppressing the temperature rise of the field winding and the armature winding to the inside of the casing. In addition, an intake port and an exhaust port for cooling air are respectively provided (for example, see Patent Document 1).

JP 2007-143366 A (6th page)

  However, since a sufficient amount of cooling air flows around the stator, the temperature rise of the generator armature winding provided in the stator core that is the stator can be suppressed. In the synchronous generator having the exciter rotor core arranged on the intake side of the rotor core, the exciter rotor core and the exciter stator core, which is a stator arranged on the outer periphery of the exciter rotor core, are used for cooling air from the intake port to the rotor core. Since the generator armature winding also becomes an obstacle to the flow, the generator field winding provided in the rotor core may not be sufficiently cooled, forming the generator field winding. There is a risk of coil burnout and dielectric breakdown. In particular, in portable engine generators used outdoors, the cooling efficiency is reduced during the summer high temperature period, so a cooling structure that can cool the coil conductor more reliably is desired.

  Therefore, an object of the present invention is to provide a cooling structure for a generator that can sufficiently cool a coil conductor wire of a rotor by guiding a part of air sucked from an intake port in the direction of the rotor.

  In order to achieve the above object, a generator cooling structure according to the present invention includes a cylindrical casing, a shaft rotatably provided on an end bracket attached to one end of the casing, and the shaft. A rotating exhaust fan, a rotor core and an exciter rotor core, a stator core fixed to the casing and disposed on the outer periphery of the rotor core, and an exciter stator core disposed on the outer periphery of the exciter rotor core are housed, and the casing is disposed at one end of the casing. In the cooling structure of a generator in which an intake port for introducing cooling air is provided and an exhaust port for extracting cooling air is provided at the other end of the casing, the first end provided on the end bracket is used as the intake port. An intake port and a second intake port that opens to the outer periphery of one end of the casing are provided. Both are characterized in that a guide member is provided on the inner periphery of the casing on the end bracket side of the second air inlet to guide the cooling air flowing into the casing from the first air inlet toward the rotor core. Yes.

  Further, in the generator cooling structure of the present invention, the second intake port is formed in a state in which a plurality of rectangular openings that open in the circumferential direction on a casing peripheral wall on the outer periphery side of the exciter stator core and the openings are covered. A guard net attached from the outside of the casing is provided, and the guide member is integrally formed on the inner peripheral side of the guard net.

  According to the generator cooling structure of the present invention, the cooling air flowing into the casing from the first intake port of the end bracket can be caused to flow in the direction of the inner peripheral rotor core by the guide member. The windings can be sufficiently cooled, and the coil conductors can be prevented from being burned out or causing breakdown. In addition, by providing the guide member integrally with the guard net attached from the outside of the casing, the guide member can be easily mounted on the inner peripheral side of the casing, and the insertion of the rotor and stator into the casing is also possible. This can be done easily before installing the net.

It is sectional drawing which shows one example of the cooling structure of the generator of this invention. It is II-II sectional drawing of FIG. It is a perspective view which shows the attachment state of a guard net.

  The generator shown in the present embodiment is generally called a brushless synchronous generator, and a rotor 13 that rotates integrally with a shaft 12 inside a cylindrical casing 11 and a stator 14 that is fixed inside the casing 11. And. One end of the shaft 12 is rotatably held at the center of an end bracket 15 attached to one end of the casing 11, and the other end of the shaft 12 is connected to an engine flywheel (not shown). .

  The rotor 13 is provided with a rotor core 16 provided in the central portion in the axial direction of the shaft 12 and an exciter rotor core 17 provided on the end bracket 15 side which is one end side of the shaft 12. On the other end side, an exhaust fan 18 for sucking and exhausting the air in the casing 11 is provided. A generator field winding 19 is assembled to the rotor core 16, and an exciter armature winding 20 and a rectifier 21 are assembled to the exciter rotor core 17.

  As the stator 14, a stator core 22 disposed on the outer periphery of the rotor core 16 and an exciter stator core 23 disposed on the outer periphery of the exciter rotor core 17 are provided. The stator core 22 has a generator armature winding. 24 is assembled, and the exciter stator core 23 is assembled with an exciter field winding 25.

  A plurality of exhaust ports 26 for leading the exhaust from the exhaust fan 18 to the outside are provided in the circumferential direction on the outer peripheral portion of the exhaust fan 18 at the other end of the casing 11. Further, on one end side of the casing 11, as an intake port for introducing cooling air into the casing 11, a first intake port 27 provided in the end bracket 15 and an outer peripheral side of the exciter stator core 23 on the peripheral wall of the casing 11 are provided. A provided second air inlet 28 is provided.

  The second air intake port 28 includes a plurality of rectangular openings 28a that are opened in the circumferential direction on the peripheral wall of the casing 11, and guard nets 28b that are respectively attached from the outside of the casing with screws or the like so as to cover the openings 28a. A net (not shown) is provided inside the plurality of ventilation holes 28c provided in the guard net 28b and inside the second intake port 28 for preventing foreign substances from entering and entraining the casing 11. ) Is stretched.

  A guide member 29 for guiding the cooling air A flowing into the casing 11 from the first air inlet 27 of the end bracket 15 toward the rotor core 16 is provided on the inner peripheral side of the guard net 28b. Yes. The guide member 29 has a conical surface shape whose diameter decreases from the proximal end 29a on the end bracket 15 side toward the distal end 29b in a state where the guide member 29 is attached to the casing 11, and the proximal end 29a is connected to the vent hole 28c. It is fixed at a position on the end bracket 15 side and formed integrally with the guard net 28b, and the tip 29b extends beyond the outer periphery of the exciter stator core 23 to a position close to the rotor core 16 and the stator core 22.

  Therefore, as described above, the cooling air A from the first air inlet 27 is guided by the inner peripheral surface of the guide member 29 and flows toward the generator field winding 19 of the rotor core 16, and the second air inlet The cooling air B that has flowed into the casing 11 from 28 flows along the outer peripheral surface of the guide member 29 and flows toward the generator armature winding 24 of the stator core 22. As a result, the generator field winding 19 and the generator armature winding 24 can be sufficiently cooled by the cooling air A and B flowing into the casing 11 from the intake ports 27 and 28, and the coil conductors Burnout and breakdown can be prevented. Further, the field current that can be passed through the generator field winding 19 can be increased without changing the structure of the casing 11.

  Further, by forming the guide member 29 integrally inside the guard net 28b, the guide member 29 can be easily and reliably disposed at a predetermined position on the inner periphery of the casing 11. Furthermore, since the guide member 29 does not protrude to the inner periphery of the casing 11 before the guard net 28b is attached, the rotor 13 and the stator 14 can be easily inserted into the casing 11 at the manufacturing stage. By removing the guard net 28b together with the guide member 29, maintenance work can be easily performed.

  The shape and mounting position of the guide member can be set as appropriate according to the size of the generator, the position of the intake port, the positional relationship between the rotor and the stator, etc. It can also be attached to any appropriate position.

DESCRIPTION OF SYMBOLS 11 ... Casing, 12 ... Shaft, 13 ... Rotor, 14 ... Stator, 15 ... End bracket, 16 ... Rotor core, 17 ... Exciter rotor core, 18 ... Exhaust fan, 19 ... Generator field winding, 20 ... Exciter Armature winding, 21 ... rectifier, 22 ... stator core, 23 ... exciter stator core, 24 ... generator armature winding, 25 ... exciter field winding, 26 ... exhaust port, 27 ... first intake port, 28 ... Second air inlet, 28a ... opening, 28b ... guard net, 28c ... vent, 29 ... guide member, 29a ... base end, 29b ... tip, A, B ... cooling air

Claims (1)

Inside the cylindrical casing, a shaft rotatably provided on an end bracket attached to one end of the casing, an exhaust fan, a rotor core and an exciter rotor core that rotate integrally with the shaft, and fixed to the casing The stator core disposed on the outer periphery of the rotor core and the exciter stator core disposed on the outer periphery of the exciter rotor core are housed, and an intake port for introducing cooling air into the casing is provided at one end of the casing, and the other end of the casing. In the generator cooling structure provided with an exhaust port through which cooling air is led out, a first intake port provided in the end bracket and a second intake port opened on the outer periphery of one end of the casing are used as the intake port. And providing a casing on the end bracket side of the second air inlet The inner circumference, wherein the guide is a guide member provided toward the first intake port of the cooling air flowing into the casing in the direction of the rotor core, the second air inlet, the outer periphery of the casing shell of the exciter stator core A plurality of rectangular openings that are open in the circumferential direction, and a guard net that is attached from the outside of the casing so as to cover the openings, and the guide member is integrally formed on the inner peripheral side of the guard net cooling structure of the generator, it characterized that you have been.

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