JPH0428211Y2 - - Google Patents

Description

[Detailed explanation of the invention] A. Purpose of the invention (1) Industrial application field The present invention is directed to a motor generator equipped with an engine and a generator section that outputs an alternating voltage of a predetermined frequency, especially the generator section thereof. The present invention relates to a motor generator that receives power from a crankshaft that penetrates one side wall of an engine crankcase via a bearing and has one end projecting outward from the outer surface of the one side wall.

(2) Conventional technology Motor generators are mainly used as portable AC power supplies, and have a larger power generation capacity than battery charging generators attached to automobile engines, so they are not equipped with windings. The overall weight of the rotor increases, and the amount of heat generated from the rotor and stator also increases. For these reasons, in conventional motor generators of this type, in order to stably support the heavy rotor without causing it to oscillate, the rotor is supported between the crankshaft and the housing on both sides, or In order to prevent the rotor and stator from overheating, it was common to attach a cooling fan to the end of the rotor on the crankcase side (for example, in Japanese Patent Application Laid-Open No. 1983-1999).
(Refer to Publication No. 86062).

(3) Problems to be solved by the invention In the above conventional structure, it is necessary to specially provide a bearing for supporting the rotor at the tip of the housing.
The rigidity of the housing must be increased accordingly, and the total length of the housing in the axial direction becomes longer (which in turn increases the total length of the generator), which causes problems such as the housing structure becoming more complicated.Furthermore, cleaning the cooling fan, There have been problems in that maintenance such as inspection cannot be performed without simply disassembling the housing and separating the rotor from the end of the crankshaft.

The present invention was proposed in view of the above, and an object of the present invention is to provide a compact motor generator that can solve the above-mentioned problems of conventional ones and also has excellent cooling performance for the engine.

B. Structure of the invention (1) Means for solving the problem In order to achieve the above object, the present invention includes an engine and a generator section that outputs an alternating current voltage of a predetermined frequency, and the generator section is connected to the engine. In a motor generator that receives power from a crankshaft that penetrates one side wall of the crankcase via a bearing and has one end protruding outward from the outer surface of the one side wall, a cylindrical base housing that projects and surrounds the one end of the crankshaft; a rotor that is disposed adjacent to the one side wall and is cantilevered on the one end of the crankshaft; a stator that is enclosed and fixed to the base housing; a cooling fan that is attached to an end of the rotor opposite to the crankcase; and an open end of the base housing that covers the cooling fan. a tip housing attached to the rotor, the rotor is wound with a field winding that cooperates with a rectifier to form an independent DC closed circuit in the rotor, and the stator has a forward A capacitor excitation winding that forms a closed circuit via a phase capacitor and a load winding to which a load is connected are wound as an unbalanced two-phase winding, and the base housing has an air intake port, and the Each of the housings is provided with an air exhaust port, and as the cooling fan rotates, outside air near the one side wall is sucked into the air intake port and exhausted from the air exhaust port.

(2) Effect The brushes are omitted from the rotor, the relatively heavy rotor can be placed close to one side wall of the crankcase without being obstructed by the cooling fan, and the relatively lightweight cooling fan can be rotated. Coupled with the fact that it is located on the side opposite to the child crankcase (i.e., on the free end side), the center of gravity of the rotating system including the rotor and cooling fan can be brought as close as possible to the bearing side of the crankcase. Therefore, the bending moment applied to one end of the crankshaft that cantilever-supports the rotating system is reduced, and lateral vibration of the rotating system is effectively suppressed.

Moreover, since the rotor is supported on a cantilever, there is no need to provide a special bearing in the tip housing on the free end side.

In addition, while the generator is operating, the rotor and stator, which generate a relatively large amount of heat, are cooled by the outside air that passes through the housing from the air intake port and is discharged from the air exhaust port. Unheated outside air can be efficiently brought into contact with the outer surface of the crankcase near the air intake port.

(3) Embodiment An embodiment of the present invention will be described below with reference to the drawings. First, in FIG. 1, the motor generator is composed of an engine E and a generator section G driven by the engine. , one end side of the crankshaft 4 of the engine E passes through one side wall 2 of the crankcase C via a bearing 5. A cylindrical base housing 2a is integrally provided on the outer surface of the one side wall 2, and this base housing 2a has the following features:
It concentrically surrounds one end 4a of the crankshaft 4 that protrudes outward from the one side wall 2.

The generator section G includes a housing 1, a stator 8 fixed to the housing, a rotor 7 surrounded by the stator 8 and cantilevered by the one end 4a of the crankshaft 4, and a rotor 7 that rotates. A cooling fan 17 attached to the child 7 is provided.

The housing 1 includes the base housing 2a
and a synthetic resin tip housing 3 that covers the open end of the base housing 2a, and the stator 8 is clamped between the base and tip housings 2a and 3.

The rotor 7 is connected to the one end 4 of the crankshaft 4.
A rotor shaft 6 concentrically connected to a, and this shaft 6
The rotor body 7m is press-fitted and fixed to the rotor body 7m adjacent to the one side wall 2 of the crankcase C, and an insertion hole 9 is formed in the shaft 6 over the entire length thereof. Screw hole 1 concentric with this insertion hole 9
A bolt 11 is inserted into the insertion hole 9 and is screwed into the screw hole 10. By tightening the bolts 11 in this manner, the rotor 7 is supported in a cantilever manner on the end of the crankshaft 4. Referring to FIG. 2, a field winding 13 is wound around the rotor body 7m, which cooperates with a rectifier such as a diode 12 to form an independent DC closed circuit.

A cooling fan 15 is supported at the end of the rotor shaft 6 opposite to the crankshaft 4 by a support member 14 fixed to the rotor shaft 6 with bolts 11 . This cooling fan 15 is formed to have a larger diameter than the inner diameter of the rotor 7.

The base housing 2a is provided with an air intake port 16 for introducing outside air near the one side wall 2, and the peripheral wall of the tip housing 3 is provided with an air intake port 16 for discharging the air that has cooled and passed through the housing 1. An air exhaust port 21 is provided. During operation of the motor generator, the rotation of the cooling fan 15 causes the rotor 7 and stator 8, which generate a relatively large amount of heat, to pass through the housing 1 from the air intake port 16 and into the air exhaust port 2.
1, and at that time, the unheated outside air before being sucked into the air intake port 16 can be efficiently brought into contact with the outer surface of the crankcase C around the air intake port 16. Therefore, engine E is also effectively cooled.

The stator 8 has a capacitor excitation winding 1 connected to a phase advancing capacitor 17 to form a closed circuit.
8 and a load winding 20 connected to the load 19 to form a closed circuit are wound as unbalanced two-phase windings so as to have a phase difference of 90 degrees in electrical angle.

Next, the operation of this embodiment will be explained. When the rotor 7 rotates in response to the rotational movement of the crankshaft 4, a phase-advanced current flows through the capacitor excitation winding 18 due to the residual magnetic flux of the rotor 7, and A positive phase rotating magnetic field having a magnetizing effect and a negative phase rotating magnetic field interlinking with the field winding 13 are generated. The reverse phase rotating magnetic field induces an alternating current voltage in the field winding 13, and the field current is rectified by the diode 12 to become a direct current. Due to the combination of the self-excitation effect due to the field current and the self-excitation effect due to the magnetizing effect of the positive-phase rotating magnetic field, the phase-advanced current of the capacitor excitation winding 18 gradually increases, and the load increases accordingly. An alternating current voltage having a phase difference with the capacitor excitation winding 18 is induced in the winding 20 , and this voltage is applied to the load 19 .

C. Effect of the invention As described above, according to the invention, the crankshaft is provided with an integral projection on the outer surface of one side wall of the crankcase.
a cylindrical base housing that surrounds one end that projects outside the crankcase; a rotor that is cantilevered on the one end of the crankshaft; and a fixing device that surrounds the rotor and is fixed to the base housing. a cooling fan attached to an end of the rotor opposite to the crankcase, and a tip housing attached to the open end of the base housing so as to cover the cooling fan; A field winding that forms an independent DC closed circuit is wound around the rotor using a rectifier, and a capacitor excitation winding that forms a closed circuit via a phase advance capacitor and a load are wound around the stator. Since the connected load winding is wound as an unbalanced two-phase winding, brushes can be omitted from the rotor, and the relatively heavy rotor can be mounted on the crankcase without being hindered by a cooling fan. The combination of the fact that it can be placed close to the side wall and the fact that the cooling fan, which is relatively lightweight, is located on the opposite side of the rotor from the crankcase (i.e., on the free end side),
The center of gravity of the rotating system including the rotor and the cooling fan can be brought as close as possible to the bearing side of the crankcase, thereby reducing the bending moment acting on one end of the crankshaft that supports the rotating system in a cantilevered manner. Therefore, even though a cooling fan is specially provided in this type of generator and the heavy rotor is cantilevered, it is not possible to effectively suppress the lateral vibration of the entire rotating system including them. can. Moreover, since the rotor is cantilevered as described above, there is no need for the free end housing to be specially provided with a bearing, and it is sufficient to simply function as a cover. By making the tip housing thinner or molding it from synthetic resin, it is possible to reduce the weight and simplify the structure.Moreover, the axial length of the entire housing can be shortened as much as possible so that it can be moved in the same direction as the engine generator. can contribute to downsizing.

Furthermore, by removing the tip housing from the base housing, the cooling fan can be widely exposed to the outside, so maintenance such as cleaning and inspection of the cooling fan can be performed without having to separate the rotor from one end of the crankshaft. It can also be done easily.

Further, the base housing is provided with an air intake port, and the tip housing is provided with an air exhaust port, and as the cooling fan rotates, outside air near the one side wall is sucked into the air intake port and exhausted from the air exhaust port. Therefore, during the operation of the motor generator, the rotor and stator, which generate a relatively large amount of heat, can be cooled by the outside air passing through the housing, and at the same time, the rotor and stator, which generate a relatively large amount of heat, can be cooled by the outside air passing through the housing. Since the previously unheated outside air can be brought into efficient contact with the outer surface of the crankcase near the air intake port, the engine itself can also be effectively cooled by the outside air.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is an overall longitudinal sectional view, and FIG. 2 is a circuit diagram. C...Crankcase, E...Engine, G...
... Generator part, 2 ... One side wall, 2a ... Base housing, 3 ... Tip housing, 4 ... Crankshaft, 4a ... One end, 5 ... Bearing, 7 ... Rotor, 8 ... Stator, 12... Diode as a rectifier, 13... Field winding, 15... Cooling fan, 16... Air intake, 17... Phase advance capacitor, 18... Capacitor excitation winding, 19... Load, 20...Load winding, 21...Exhaust port.

Claims (1)

[Claims for Utility Model Registration] (1) Comprising an engine E and a generator section G that outputs an alternating current voltage of a predetermined frequency, the generator section G:
It penetrates one side wall 2 of the crankcase C of the engine E via the bearing 5, and the one end 4a is connected to the one side wall 2.
In a motor generator configured to receive power from a crankshaft 4 protruding outward from an outer surface, a cylinder is integrally provided on the outer surface of the one side wall 2 of the crankcase C and surrounds the one end 4a of the crankshaft 4. a rotor 7 disposed adjacent to the one side wall 2 and cantilevered by the one end 4a of the crankshaft 4;
a stator 8 fixed to the rotor 7, a cooling fan 15 attached to the end of the rotor 7 opposite to the crankcase C, and a cooling fan 15 attached to the open end of the base housing 2a so as to cover the cooling fan 15. A field winding 13 is wound around the rotor 7 to form an independent DC closed circuit in cooperation with a rectifier 12 in the rotor 7. 8, a capacitor excitation winding 18 forming a closed circuit via a phase advancing capacitor 17 and a load winding 20 to which a load 19 is connected are wound as an unbalanced two-phase winding, and the base housing 2a has an air intake port 16
However, the tip housing 3 also has an air exhaust port 21.
A motor generator characterized in that, by rotation of the cooling fan 15, outside air near the one side wall 2 is sucked into the air intake port 16 and discharged from the air exhaust port 21. (2) The motor generator according to claim 1, wherein the cooling fan 15 is formed to have a larger diameter than the inner diameter of the stator 8.