JPH11275810A - Engine generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an engine generator which can be constituted of a small number of parts at low cost, enables reduction of annoying press-fitting operations and fastening operations, allows a stator and a rotor to be efficiently assembled, and is superior in productivity. SOLUTION: This engine generator comprises a stator housing case 2 provided with a single bearing assembly 8, which supports the crank shaft 4 of an engine E in such a manner such that the crank shaft 4 is turnable, a stator 6 secured on the inner surface of the case 2, a rotor 5 which is fit onto the crank shaft 4 and the outer surface of which is held via a microscopic gap g between it and the inner surface of the stator 6, a rotor fan 7 secured at the outer end of the crank shaft 4 with a single rotor bolt 13, and a cover 13 which covers the rotor fan 7. The rotor 5 is clamped on both its ends between a rotor anchoring member 7d, 7 and a rotor anchoring stepped portion 4b1 and is thereby secured. The stator 6 is clamped on both its ends between a stator anchoring stepped portion 2c and a stator anchoring member 11 so as to secure the stator.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine generator in which a rotor is rotated with a crankshaft which is rotated by driving an engine, and the rotation of the rotor generates electric power in a stator.

[0002]

2. Description of the Related Art An engine generator generally used at present is, for example, as shown in FIG. The engine generator 20 shown here includes inner and outer housings 21 and 22 fixed to a side end of a crankcase C, and a stator 23 held between the housings 21 and 22.
And a generator cover 24 that covers the outer end of the outer housing 21, the outer shell of which is formed. A bearing 25 provided at the center of the bottom of one of the housings 21 has a crank 25 for the engine e. A shaft 34 is rotatably supported, and the other housing 22
One end of a pipe-shaped rotor shaft 27 is rotatably supported by a bearing 26 fixed to the center of the shaft.

The other end of the rotor shaft 27 has a tapered fitting surface 2 whose diameter increases toward the tip.
The crankshaft 34 is fitted on the fitting surface 27a. And the two shafts 2
7, 34 are connected by screwing a long bolt 28 inserted from the outer end of the rotor shaft 27 into a screw hole 34a formed at one end of the crankshaft 34, and rotate together with the crankshaft 34. It has become something. A rotor 29 is fixed to the rotor shaft 27, and an outer surface of the rotor 29 faces an inner surface of the stator 23 via a predetermined gap.

Further, the two housings 21 and 22 are
A plurality of (three in this case) long stator bolts 30 are connected to each other, and the stator 23 is fastened to the two housings 21 by fastening the respective stator bolts 30.
22 so as to be firmly held. Also, on the outer periphery of one end of the crankshaft 27,
An annular rotor fan bracket 32 is press-fitted and fixed, and the rotor fan 31 is fixed to the rotor fan bracket 32 with a plurality of screws 33.

In the generator having the above configuration, the engine e
Is driven, the reciprocating motion of the piston p is converted into the rotation of the crankshaft 34 via the connecting rod r, and the rotor shaft 27 connected to the crankshaft 34 rotates to rotate the rotor 29, The electric power is generated in the stator 23 to be driven. At this time, the rotation of the rotor shaft 27 causes the rotor fan 3 to rotate.
1 rotates, external air introduced from the housing 21 is supplied to the stator 23 and the like, and is discharged from the cover 24. The heat generated during power generation is generated by the air sucked by the rotor fan 31. Cooled by.

[0006]

However, the conventional engine generator 20 has a problem that the structure is complicated, the number of parts is large, and the assembling work is difficult, so that the manufacturing cost is increased. Was. That is, since the rotation of the crankshaft 34 is transmitted to the rotor 29 via the rotor shaft 27, a high precision is required for the connecting portion between the two shafts 27 and 34, and The fastening and fixing of the 34 require long bolts 28 and 30 that are out of the standard, so that the production of such special parts requires a lot of costs, and the cost of the entire apparatus is greatly increased. .

Further, since it is necessary to maintain a small gap between the rotor 29 and the stator 23, high precision is required for holding the rotor 29. However, in the prior art, the rotor fan 31 is interposed between the rotor 29 and the bearing 25, and the distance from the bearing 25 to the rotor 29 is increased. 27 and the crankshaft 34 are likely to generate vibration. For this reason, in order to suppress the vibration, the shafts 27 and 34 must be held at two places, and two expensive bearings are required, which causes a cost increase. Furthermore, since the bracket 32 and the plurality of bolts 33 are used for fixing the rotor fan 31, the number of parts is large, which also causes an increase in cost.

In the assembling process, in addition to press-fitting the rotor 29 into the rotor shaft 27, press-fitting the two bearings 25, 26 into the respective housings, and inserting the crankshaft 34 and the rotor shaft 27 into the respective bearings 25, 26. A complicated press-fitting operation such as press-fitting and press-fitting of the rotor fan bracket 32 into the rotor shaft 27 needs to be performed many times, and the number of bolts to be tightened is large, so that the assembly process becomes complicated. was there.

In particular, since the rotor 29 is press-fitted into the rotor shaft 27, it is difficult to position the rotor 29, and it is not possible to obtain a strong fixed state on the rotor 29. Since the housing 22 has a structure that holds the rotor shaft 27 and the rotor 29 and also fixes the stator 23, a large number of components such as the bearing 26, the rotor shaft 27, the rotor 29, and the rotor fan are assembled during assembly. Since the stator 23 must be fixed by the housing 22 in which the housing 22 incorporates a large number of components, the fixing operation of the stator 23 is complicated and difficult.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and can be firmly constructed with a small number of parts at low cost, and can reduce troublesome press-fitting work and tightening work. It is another object of the present invention to provide an engine generator excellent in productivity and capable of efficiently assembling a stator and a rotor.

[0011]

The present invention has the following arrangement to solve the above-mentioned problems. That is, the present invention provides a bowl-shaped stator storage case having a bearing portion rotatably supporting a crankshaft that is rotated by driving of an engine, and an annular stator fixed to an inner surface of the stator storage case by stator fixing means. A stator having a through-hole into which a crankshaft extending inward of the stator is inserted, and a rotor rotating with the crankshaft, the outer surface of which is held through a predetermined minute gap from the inner surface of the stator; Rotor restricting means for restricting the position of the rotor in the axial direction of the crankshaft, a rotor fan whose center is fastened by a single rotor bolt screwed to the outer end of the crankshaft, A cover fastened to the opening edge of the stator storage case so as to cover the rotor, A rotor locking step formed on the crankshaft; and a rotor locking member fastened and fixed to the crankshaft so as to protrude outward from an outer peripheral surface thereof. The stator fixing means is configured to sandwich both ends of the rotor between the step and the step. A stator locking member to be fastened and fixed is provided, and an outer peripheral portion of the stator is sandwiched and fixed from both ends thereof between the stator locking step and the stator locking member.

The rotor restricting means includes, for example, an annular rotor engaging step formed on a crankshaft, and an annular rotor fastening and fixing together with a rotor fan to an outer end of the crankshaft by a rotor bolt. It is conceivable to fix and fix the rotor from both ends thereof between the rotor locking step and the rotor locking plate, and the stator fixing means includes a stator housing case. An annular souta locking step protruding from the inner surface of the
A stator locking plate as a stator locking member that is screwed and fixed to a mounting portion protruding from an edge of the opening of the stator storage case with a screw and protrudes inward from an inner surface of the stator storage case. It is conceivable that both ends of the stator are clamped and fixed between the stator locking plate and the stator locking step by fastening and fixing the stator locking plate.

[0013] Further, the stator locking plate is formed integrally with the fastening portion, which is fastened and fixed by a screw to a mounting portion protruding from an edge of the opening of the stator storage case. It is conceivable that the stator housing has a projection that protrudes from the inner surface of the stator housing, and has a specific shape, for example, an arc shape, and is fastened to two symmetrical locations at the opening edge of the stator housing. It is possible to wear and fix.

In the present invention having the above-described structure, the rotor and the rotor fan are sequentially provided outwardly on the crankshaft which is cantilevered by the single bearing provided in the stator housing case. , The distance between the rotor fan and the bearing can be minimized, and even if the rotor fan is cantilevered, the gap between the rotor and stator can be properly adjusted without being affected by engine vibration. , Interference between the rotor and the stator can be prevented, and a stable operation can be obtained. Further, since the crankshaft is supported in a cantilever manner, the number of bearings 8 can be reduced as compared with the related art, and the press-fitting operation process required for the bearings 8 can be reduced.

Further, an outer shell for accommodating the stator and the rotor fan is formed by a cover fixed to the edge of the opening of the stator housing case extended in the front-rear direction corresponding to the length of the stator. Therefore, the outer shell structure can be simplified as compared with the conventional case where the outer shell is formed by the two brackets, the generator cover and the stator. In addition, since the bolts for fastening the rotor and the like need only be short, standard products can be used, and the configuration can be made at low cost.

Further, if both ends of the rotor are sandwiched between the rotor locking step formed on the crankshaft and the rotor locking member as in the rotor fixing means, a troublesome press-fitting operation can be performed. It is not necessary, and it is possible to perform positioning work in the longitudinal direction at the same time as positioning work.
Good workability can be obtained. In particular, if the rotor and the rotor locking member are fixed to the crankshaft by tightening together, the fixing operation can be performed more easily and quickly.

Further, if both ends of the stator are sandwiched and fixed between a stator locking plate fastened and fixed to the stator storage case and a stator locking step like a stator fixing means, Since the operation of fixing the stator to the stator and the stator housing case can be performed independently of the operation of fixing the rotor and the like, the operation can be performed efficiently and quickly. Further, if the stator locking step is formed in an annular shape and the locking step is formed in an arc shape, a more stable fixed state can be obtained.

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is an explanatory diagram of a generator 1 according to an embodiment of the present invention. As shown in the figure, a generator according to the present embodiment includes a bowl-shaped stator storage case 2 integrally projecting from a side of a crankcase C of an engine E, and an opening of the stator storage case 2. And a generator cover 3 provided therein, an outer shell having a hollow body structure is formed. Inside the outer shell structure, a crankshaft 4, a rotor 5, a stator 6, a rotor fan 7, and the like are as follows. It is provided in.

That is, a bearing insertion port 2b is formed in the center of the bottom of the stator housing case 2, and a bearing 8 is press-fitted and fixed therein. The bearing (bearing portion) 8 includes a piston P when the engine is driven.
The crankshaft 4 rotated by the vertical movement is press-fitted and protrudes inward. The crankshaft 4 is formed concentrically with a peripheral surface portion having three diameters, a large diameter portion 4a, a medium diameter portion 4b, and a small diameter portion 4c. The middle diameter portion 4b is press-fitted into the bearing 8, and the end surface of the large diameter portion 4a abuts on the end surface of the bearing 8, so that the position in the longitudinal direction is determined.

The outer end of the crankshaft 4 (the front end of the small diameter portion 4c) extends to the edge of the opening 2a of the stator housing case 2. A keyway 4c1 having a predetermined length and depth is formed on the peripheral surface of the small diameter portion 4c of the crankshaft 4 along the longitudinal direction (the direction of the central axis) from the front end. 4
The straight key 9 is inserted into c1. Further, a screw hole 4c2 for screwing the rotor bolt 13 is formed at the outer end of the crankshaft 4.

The stator 6 is shown in FIGS.
As shown in FIG. 1, a conductor is wound around an annular iron core 6a to form an annular coil 6b, which is fixed to the inner surface of the stator housing case 2 by stator fixing means. This stator fixing means includes a stator locking step 2c formed on the inner surface of the stator housing case 2 and an arc-shaped mounting portion 2d formed at two symmetrical locations in the opening 2a of the stator housing case 2 (FIG. 3 and 8) and two stator locking plates (stator locking members) 11 fixed to the front end face of each mounting portion 2d with screws 10. Each of the stator locking plates 11 includes a fastening portion 11a fastened and fixed by a screw 10 to a mounting portion 2d protruding from an edge of the opening of the stator storage case, and a fastening portion 1a.
1a and a protruding portion 11b integrally formed and protruding from the inner surface of the stator housing case.

By fixing the stator locking plate 11 with the screws 10 in a state where one end of the iron core 6a of the stator 6 is in contact with the stator locking step 2c, the stator 6 has both ends. The portion is the protrusion 11 of the stator locking plate 11
b and the stator locking step 2c, and is firmly fixed. In this embodiment, as shown in FIGS. 2 and 3, the stator locking step 2c has an annular shape, and the stator locking plate 11 has an arc shape. It can be clamped uniformly, and a stable and firm fixed state can be obtained.

As shown in FIGS. 1 and 4, the rotor 5 has an iron core 5 having a pair of arc-shaped outer peripheral surfaces.
and a coil 5b formed by winding a conductive wire around the iron core 5a. A small-diameter portion 4 of the crankshaft 4 is provided in a through hole 5a1 formed at the center of the iron core 5a.
c is inserted, and the edge of the opening of the through hole 5a1 abuts on the end surface 4b1 of the middle diameter portion 4b of the crankshaft 4 to prevent the crankshaft 4 from moving toward the middle diameter portion 4b. Also,
On the inner peripheral surface of the iron core 5a, a key groove 5a2 is formed along the central axis direction, and this key groove 5a2 is
The straight key 9 is inserted into the key groove 4c1 of the small diameter portion 4c of the crankshaft 4. For this reason, the rotor 5 and the crankshaft 4 are locked in the turning direction via the straight key 9, and both rotate integrally. The outer peripheral surface of the iron core 5a of the rotor 5 is opposed to the inner peripheral surface of the iron core 6a of the stator 6 via a small gap g.

The rotor fan 7 is formed as shown in FIGS. 1 and 6, and has a horn-shaped central portion having a diameter gradually increasing outward from a cylindrical mounting portion 7a. Fins 7c protrude from the outer surface of the plate 7b, and a screw insertion hole 7 is provided at the center of the mounting portion 7a.
a1 is formed and a single rotor bolt 1 inserted therethrough
3 is a screw hole 4 formed at the tip of the crankshaft 4
By screwing into c2, it is fastened and fixed.

A ring-shaped rotor locking plate 7d is fitted in a recess formed in the end face of the center portion of the rotor fan 7, and this rotor locking plate 7d is attached when the rotor fan 7 is mounted. The small-diameter portion 4c of the crankshaft 4 comes into contact with the outer end surface. For this reason, the rotor 5 includes a rotor locking plate 7 d of the rotor fan 7 and an end face (rotor locking step) 4 of a middle diameter portion 4 b of the crankshaft 4.
b1 so as to be positioned in the axial direction. Note that the rotor fan 7, the rotor locking plate 7d, the rotor locking step 4b1 of the middle diameter portion 4b, and the rotor screw 13 constitute a rotor restricting means. The generator cover 3 has a container shape. As shown in FIG. 7, an exhaust port 3a is formed in a side surface portion, and a cutout portion into which a protruding portion 11b of the stator locking plate 11 is inserted is formed. It is fastened and fixed to the opening edge of the stator 6 by a screw (not shown).

In the engine generator having the above configuration, when the crankshaft 4 rotates via the connecting rod R due to the reciprocating motion of the piston P, the crankshaft 4
, The rotor 5 engaged by the key 9 rotates together,
Electric power is generated in the stator 6. Rotor 5 and bearing 8
The rotor 5 is disposed as close to the bearing 8 as possible without any intervening member between them. Therefore, even if vibrations such as vibrations generated in the engine E occur in the surroundings, the rotors 5 are affected. The small gap g formed between the rotor 5 and the stator 6 is always kept constant, and there is no possibility that the rotor 5 will interfere with the stator 6.

Further, the rotor fan 7 also rotates with the rotation of the rotor 5, and the air heated by the stator 6 and the like in the generator is exhausted from the exhaust port 3 a of the generator cover 3, while the air enters the stator housing case 2. Since low-temperature external air is introduced and the air is blown to the stator 6 and the rotor 5, the stator 6 and the rotor 5 are surely cooled. Moreover, in this embodiment, since the rotor fan 7 is provided outside (in front of) the rotor 5, the rotor fan 7 is not affected by the dimensions and the shape of the stator housing case 2 and the like, and depends on the required air volume. 7 and the height of the fins 7c can be set, and desired cooling performance can be obtained.

Further, as described above, in the engine generator 1 of this embodiment, since the crankshaft 4 projecting inward is supported in a cantilever state, it is extremely inexpensive and requires a small number of parts as compared with the prior art. And assembling can be easily performed. That is, upon assembling, the bearing 8 is fitted into the bearing insertion hole 2 b of the stator housing case 2, the crankshaft 4 is pressed into the bearing 8, and the stator housing case 2 is held by the crankshaft 4. Next, the stator 6 is placed in the stator storage case 2.
Is inserted until one end thereof comes into contact with the stator locking step 2c, and the stator 6 is fixed by fastening and fixing the stator fixing plate 11 with the screw 10. After this, keyway 5
The straight key 9 is inserted into a2, and the rotor 5 is inserted into the small diameter portion 4c of the crankshaft 4 while engaging the straight key 9 with the key groove 5a2. Here, the rotor fan 7 and the rotor 5 are fastened together and fixed to the crankshaft 4 with the rotor bolts 13. Finally, fasten the fan cover.

As described above, in this embodiment, two press-fitting operations involving the bearing 8 and the rotor bolt 1
3 can be performed by jointly fastening the rotor fan 7 and the rotor 5. On the other hand, in the conventional engine generator, four press-fitting operations involving the two bearings 8 are required, and the fastening operation also includes fixing of the rotor 29,
Since it is necessary to perform each operation for fixing the rotor fan 31, the operation is greatly simplified according to this embodiment, and the labor and time required for the operation are greatly reduced.

Further, in this embodiment, since the outer shell of the generator is constituted by the two parts of the stator housing case 2 and the generator cover 3, the outer shell is formed by the inner and outer housings 21, 22 and the generator cover 24 as in the prior art. First, the number of parts is reduced in the outer shell structure compared to the shell structure, and further, as the inner structure,
The number of bearings 8 has been reduced from two to one,
The number of screws to be used is reduced as described above, and the rotor shaft, which has been conventionally required, is not required. In addition, the screws used in this embodiment are all short and can be used within the range of the standard, so that the cost of the screws themselves is reduced.

The stator 6 can be fixed by fixing the stator locking plate 11 to the storage case 2, and the rotor 5 can be fixed by screwing the screw 13 to the crankshaft 4.
The fixing work of the rotor 5 and the stator 6 can be performed independently of each other, and both the rotor 5 and the stator 6 abut against the locking step portions 2c and 4b1. Therefore, the fixing operation and the positioning operation can be performed at the same time, and the operation can be performed extremely efficiently.

In the above-described generator, it is necessary to change the distance (width) between both ends in the axial direction of the stator, the rotor, and the like according to the power generation capacity. That is, the width of the stator and the rotor needs to be increased as the power generation capacity of the generator to be obtained increases. Therefore, for example, in the case of the one shown in FIG. 1 which can obtain a higher output, the width from the stator housing case 2 to the generator cover 3 needs to be increased as the width of the stator 6 and the rotor 5 is increased. However, in this embodiment, it is possible to easily cope with the situation by preparing the stator locking plates 11 having different thicknesses in the fastening portions 11a and the screws 10 having different lengths.

For example, as shown in FIG. 8 (a), when there are three types of the width of the stator 6 to be housed, that is, large, medium, and small, the stator locking plate 11 also has the mounting portion 11a.
8 (a), 8 (b) and 8 (c) are prepared, and when the width of the stator 6 is small, the stator shown in FIG. When the width of the stator 6 is medium, the locking plate 11 shown in FIG. 3B is used. When the width of the stator is large, the locking plate 11 shown in FIG. What is necessary is just to use the stop plate 11, respectively.
A common member can be used for the stator storage case 2 and the generator cover 3. However, since the gap between the generator cover 3 and the stator housing case 2 changes according to the width of the stator 6, depending on the size of this gap, the width of the generator cover 3 and the notch 3
It may be desirable to change the width of b, 3b.

In the above-described embodiment, the stator locking step 2c and the rotor locking step 4b1 are formed in an annular shape. However, these locking steps are not limited to a continuous shape like a ring. For example, arc-shaped or other shapes may be provided intermittently.Also, even in the case of the stator locking plate, various shapes other than the arc shape, for example, an annular shape or a rectangular shape, may be used. Can be applied.

[0035]

As described above, in the present invention,
Since the rotor and the rotor fan are sequentially provided outward with respect to the crankshaft supported by a single bearing provided in the stator housing case, the distance between the rotor fan and the bearing is provided. Can be minimized, and even if the rotor fan is supported in a cantilever manner, the gap between the rotor and the stator can be properly maintained without being affected by vibration of the engine. Interference can be prevented, and stable operation can be obtained. Further, since the crankshaft is supported in a cantilever manner, the number of bearings can be reduced as compared with the conventional case, and the press-fitting operation steps required for the bearings can be reduced.

Further, the stator housing case is extended in the front-rear direction corresponding to the length of the rotor, and the stator and the rotor fan are housed by the cover fixed to the edge of the opening. Can also be simplified. In addition, since the bolts for fastening the rotor and the like need only be short, standard products can be used, and the configuration can be made at low cost.

Furthermore, if both ends of the rotor are sandwiched between the rotor locking step formed on the crankshaft and the rotor locking member, a troublesome press-fitting operation is not required.
A position regulating operation in the longitudinal direction can be performed simultaneously with the positioning operation, and good workability can be obtained. In particular, if the rotor fan and the rotor locking member are fixed to the crankshaft by fastening together, the fixing operation can be performed more easily and quickly.

Further, if the both ends of the stator are sandwiched and fixed between the stator locking plate and the stator locking step which are fastened and fixed to the stator housing case like the stator fixing means, Since the operation of fixing the stator to the stator storage case can be performed independently of the operation of fixing the rotor and the like, the operation can be performed efficiently and quickly, and excellent productivity can be obtained. Further, if the stator locking step is formed in an annular shape and the locking step is formed in an arc shape, a more stable fixed state can be obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view showing an embodiment of the present invention.

FIG. 2 is a front view showing a stator storage case and a locking plate shown in FIG. 1;

FIG. 3 is an explanatory perspective view showing a state shown in FIG. 1 as viewed from an arrow X;

FIG. 4 is a perspective view showing a stator in FIG. 1;

FIG. 5 is a front view showing the rotor in FIG. 1;

FIG. 6 is a front view showing the rotor fan in FIG. 1;

FIG. 7 is a front view showing the inner surface of the generator cover in FIG. 1;

FIG. 8 is a view showing various stator locking plates in the embodiment of the present invention.

FIG. 9 is a vertical sectional side view showing a conventional engine generator.

[Explanation of symbols]

 E Engine C Crankshaft 1 Engine generator 2 Stator storage case 2c1 Stator locking step 3 Cover 4 Crankshaft 4b1 Rotor locking step 5 Rotor 6 Stator 7 Rotor fan 7d Rotor locking plate 8 Bearing 10 Screw 11 Stator locking Plate 13 Rotor bolt

Claims (4)

[Claims] 1. A bowl-shaped stator storage case having a bearing for rotatably supporting a crankshaft rotated by driving of an engine, and an annular stator fixed to an inner surface of the stator storage case by stator fixing means. A rotor having a through-hole into which a crankshaft extending inward of the stator is inserted, the outer surface being held through a predetermined minute gap from the inner surface of the stator and rotating with the crankshaft; Rotor restricting means for restricting the position of the rotor in the axial direction of the crankshaft; a rotor fan having a central portion fastened by a single rotor bolt screwed to an outer end of the crankshaft; and covering the rotor fan. A cover fastened to the opening edge of the stator housing case, A rotor locking step formed on the shaft; and a rotor locking member fastened and fixed to the crankshaft so as to protrude outward from an outer peripheral surface thereof. The rotor is configured to hold both ends of the rotor between the stepped portion and the stator fixing means, and the stator fixing step projects from the inner surface of the stator storage case and protrudes from the inner surface of the stator storage case. A stator locking member to be fastened and fixed, wherein the outer peripheral portion of the stator is sandwiched between both ends of the stator between the stator locking step portion and the stator locking member.
An engine generator characterized by being configured to be fixed. 2. A rotor restricting means comprising: an annular rotor locking step formed on a crankshaft; and an annular rotor locking fastened and fixed together with a rotor fan to an outer end of the crankshaft by a rotor bolt. 2. The engine generator according to claim 1, further comprising a plate, wherein the rotor is sandwiched between both ends of the rotor locking step and the rotor locking plate. 3. A stator fixing means comprising: an annular stator locking step protruding from an inner surface of a stator storage case; and a fixing part protruding from an edge of an opening of the stator storage case, which is fastened by a screw. A stator locking plate as a stator locking member which is fixed and protrudes inward from the inner surface of the stator storage case; and the stator locking plate is fixed to the stator locking plate by fastening and fixing the stator locking plate. The engine generator according to claim 1, wherein both end portions of the stator are sandwiched and fixed between the stop portion and the stop portion. 4. The stator locking plate according to claim 1, wherein the stator locking plate has an arc shape and is fastened and fixed to two symmetrical positions at the opening edge of the stator housing case. Engine generator.