阅读说明：本技术 增压器 (Pressure booster ) 是由 辻刚志 小野嘉久 西村英高 平川一朗 于 2018-12-07 设计创作，主要内容包括：本发明的目的是提供一种即使为联轴器构造的增压器也可以将流体高效地向叶轮引导,并可以实现马达或发电机的冷却性能的提高的增压器。具备：吸入部(10b),该吸入部吸入流体；叶轮(12),该叶轮对从吸入部(10b)供给的流体进行压缩；驱动轴(18),在该驱动轴的一端安装有叶轮(12)；中间轴(16),该中间轴以使驱动轴(18)沿轴线方向从叶轮(12)的下游侧向上游侧延长的方式设于驱动轴(18)的一端；马达(14)或发电机,该马达或发电机具有借助接头(20a)安装在中间轴(16)的顶端的转子(14a)、与转子(14a)对应地设置的定子(14c),和保持定子(14c)的主体部(14b)；以及罩(30),该罩为包围中间轴(16)及接头(20a)的筒状。(The purpose of the present invention is to provide a supercharger that can efficiently guide fluid to an impeller even in a supercharger having a coupling structure, and can improve the cooling performance of a motor or a generator. The disclosed device is provided with: a suction unit (10b) that sucks in fluid; an impeller (12) that compresses the fluid supplied from the suction portion (10 b); a drive shaft (18) to one end of which an impeller (12) is attached; an intermediate shaft (16) provided at one end of the drive shaft (18) so that the drive shaft (18) extends from the downstream side to the upstream side of the impeller (12) in the axial direction; a motor (14) or a generator having a rotor (14a) attached to the tip end of an intermediate shaft (16) via a joint (20a), a stator (14c) provided corresponding to the rotor (14a), and a main body portion (14b) holding the stator (14 c); and a cover (30) having a cylindrical shape surrounding the intermediate shaft (16) and the joint (20 a).)

1. A supercharger is characterized by being provided with:

a suction portion that sucks in a fluid;

an impeller that compresses fluid supplied from the suction portion;

a drive shaft to one end of which the impeller is attached;

an intermediate shaft provided at the one end of the drive shaft so as to extend from a downstream side to an upstream side of the impeller in an axial direction;

a motor or a generator having a rotor attached to a tip end of the intermediate shaft via a joint, a stator provided corresponding to the rotor, and a main body portion holding the stator; and

and a cover having a cylindrical shape surrounding the intermediate shaft and the joint.

2. The supercharger of claim 1,

the suction part is provided on an upstream side of the motor or the generator,

the inner diameter of the shroud is greater than the outer diameter of the rotor.

3. The supercharger of claim 1,

the outer diameter of the cover is the same as the outer diameter of the cover-side end portion of the hub of the impeller.

4. The supercharger of claim 1,

the cover is dividable in the long dimension direction.

5. The supercharger of claim 1,

the cover is provided with ribs along the long dimension direction.

6. The supercharger of claim 1,

the cover is mounted on the motor side or the generator side.

Technical Field

The present invention relates to a supercharger suitably used for a diesel engine or the like provided in a ship, for example.

Background

Conventionally, a supercharger that compresses air and supplies the compressed air into a combustion chamber as combustion air for an internal combustion engine is known. Superchargers are also widely used in two-stroke low-speed engines such as marine diesel engines and power generation diesel engines. In such a supercharger, a compressor for compressing combustion air and a turbine serving as a drive source of the compressor are coupled by a rotor shaft, and are housed in a casing and integrally rotated. The turbine is driven by, for example, exhaust gas discharged from an internal combustion engine as a drive source.

As one type of supercharger, a hybrid supercharger in which an electric motor is connected to a rotor shaft via a joint is known (for example, see patent document 1). This hybrid supercharger can not only compress air and supply the compressed air as combustion air into the combustion chamber of the internal combustion engine, as in a conventional supercharger, but also generate electricity by the excess exhaust gas discharged from the internal combustion engine.

As one type of supercharger, an electric-assisted supercharger in which an electric motor is connected to a rotor shaft is known (for example, see patent document 2). The electric booster is reduced in size to a motor function (assist function) without the generator function of a motor generator used in the hybrid booster, thereby reducing the size of the motor.

Disclosure of Invention

The present invention has been made in view of such circumstances, and an object thereof is to provide a supercharger that can efficiently guide fluid to an impeller even in a supercharger having a coupling structure, and can improve cooling performance of a motor or a generator.

Means for solving the problems

In order to solve the above problem, the following means is adopted in the supercharger.

That is, a supercharger according to one mode of the present invention includes: a suction portion that sucks in a fluid; an impeller that compresses fluid supplied from the suction portion; a drive shaft to one end of which the impeller is attached; an intermediate shaft provided at the one end of the drive shaft so as to extend from a downstream side to an upstream side of the impeller in an axial direction; a motor or a generator having a rotor attached to a tip end of the intermediate shaft via a joint, a stator provided corresponding to the rotor, and a main body portion holding the stator; and a cover having a cylindrical shape surrounding the intermediate shaft and the joint.

The supercharger according to this mode is a coupling structure in which a rotor is attached to the tip end of an intermediate shaft via a joint. The intermediate shaft and the joint are surrounded by a cylindrical cover. According to this configuration, the flows of fluid flowing into the impeller can be separated outside and inside the shroud by the shroud, and interference between the flows of fluid can be suppressed. Further, the flow path area around the cover can be uniformly reduced in the flow direction of the fluid. This can rectify the flow of the fluid while reducing the pressure loss of the fluid flowing into the impeller, thereby preventing the fluid from decelerating. Further, the flow rate of the fluid flowing into the impeller can be ensured to be sufficient. That is, the fluid can be efficiently guided to the impeller. At the same time, the fluid can be also surely guided into the motor or the generator (between the rotor and the stator), and therefore, the cooling performance of the motor or the generator by the fluid can be improved.

The cylindrical cover does not need to surround the entire intermediate shaft in the longitudinal direction, but may surround a part of the intermediate shaft.

In the supercharger according to one mode of the present invention, the suction portion is provided upstream of the motor or the generator, and an inner diameter of the cover is larger than an outer diameter of the rotor.

In the supercharger according to this mode, the suction portion is located upstream of the motor or the generator, and the inner diameter of the cover is larger than the outer diameter of the rotor. This makes it possible to reliably guide the fluid into the motor or the generator, and thus to improve the cooling performance of the motor or the generator by the fluid. Therefore, the output power can be increased without changing the model of the motor or the generator. Further, it is not necessary to additionally provide a cooling mechanism for cooling the motor or the generator, and cost reduction can be achieved.

Further, in the supercharger according to one mode of the present invention, an outer diameter of the cover is the same as an outer diameter of the cover-side end portion of the hub of the impeller.

In the supercharger according to this mode, the outer diameter of the cover is the same as the outer diameter of the cover-side end portion of the hub. This ensures the flow path area of the fluid flowing into the impeller, and smoothes the flow of the fluid.

Further, in the supercharger according to one mode of the present invention, the cover may be divided in the longitudinal direction.

In the supercharger according to this mode, the cover can be divided in the longitudinal direction. Since the part where the cover is attached is densely provided with a motor (or a generator), an intermediate shaft, a joint, and the like, the working space is limited. By making the cover dividable, the ease of assembly can be improved.

Further, in a supercharger according to one mode of the present invention, the cover is provided with ribs in the longitudinal direction.

In the supercharger according to this mode, the cover is provided with ribs in the longitudinal direction. This ensures strength even when the cover has a thin-walled structure. That is, the cover can be reduced in weight and can secure strength.

Further, in a supercharger according to one mode of the present invention, the cover is attached to the motor side or the generator side.

In the supercharger according to this mode, the cover is attached to the motor side or the generator side. This eliminates the need to additionally provide a support structure for installing the cover, and thus can reduce the cost.

Effects of the invention

According to the supercharger of the present invention, even in the supercharger having the coupling structure, the fluid can be efficiently guided to the impeller, and the cooling performance of the motor or the generator can be improved.

Drawings

Fig. 1 is a longitudinal sectional view showing a supercharger according to an embodiment of the present invention.

Fig. 2 is a sectional view taken along a cutting line a-a of the motor shown in fig. 1.

Fig. 3 is a right side view of the upper housing shown in fig. 1.

Fig. 4 is a bottom view of the upper cover shown in fig. 3.

Fig. 5 is a right side view of the lower housing shown in fig. 1.

Fig. 6 is a top view of the lower housing shown in fig. 5.

Detailed Description

Hereinafter, a supercharger according to an embodiment of the present invention will be described with reference to the drawings.

First, the structure of the supercharger 10 of the present embodiment will be described.

The supercharger 10 is, for example, a supercharger such as a hybrid supercharger or an electric-assisted supercharger, which is used when the combustion efficiency of a diesel engine (internal combustion engine) for a ship is improved by increasing the pressure of air (gas) supplied to the diesel engine to a fixed pressure (for example, atmospheric pressure) or higher.

As shown in fig. 1, the supercharger 10 includes a drive shaft 18, a compression section 10a, an intermediate shaft 16, a motor 14, an intake section 10b, and a cover 30.

The compressor 10a is provided with an impeller 12. The impeller 12 includes a hub 12d and a plurality of blades 12c provided on the hub 12 d. The impeller 12 is attached to one end side of a drive shaft 18, and the drive shaft 18 is supported by a bearing (not shown) so as to be rotatable about the axis X. A turbine (not shown) that is rotationally driven by exhaust gas discharged from the diesel engine is provided on the other end side of the drive shaft 18. That is, the impeller 12 provided in the compression portion 10a is coupled to a turbine (not shown) via a drive shaft 18.

On one end side of the drive shaft 18 to which the impeller 12 is attached, an intermediate shaft 16 coaxial with the drive shaft 18 is provided along a direction in which the drive shaft 18 extends along the axis X from the impeller 12 to the upstream side of the air flow (from the right side to the left side in fig. 1). The drive shaft 18 and the intermediate shaft 16 are coupled by a second joint 20 b. Instead of providing the second joint 20b, the drive shaft 18 may be extended in the axial direction, and the extended portion of the drive shaft 18 may be a shaft corresponding to the intermediate shaft 16.

On the other hand, the motor 14 is provided on the end portion side (left side in fig. 1) of the intermediate shaft 16 not coupled to the drive shaft 18. The motor 14 includes a rotor 14a, a stator 14c provided with a gap in a radial direction of the rotor 14a, and a body portion 14b holding the stator 14 c. The body portion 14b includes a plurality of support members 14d extending in the radial direction. The stator 14c is supported by the housing 10c of the supercharger 10 by the body portion 14b including the support members 14 d.

Both ends of the rotor 14a are rotatably supported about the axis X by bearings 14e provided in the main body portion 14 b. The intermediate shaft 16 side (right side in fig. 1) end of the rotor 14a is coupled to the intermediate shaft 16 via a first joint 20 a.

As described above, the supercharger 10 of the present embodiment has a so-called coupling structure in which the rotor 14a is attached to the end of the intermediate shaft 16 via the first joint 20 a.

An intake portion 10b of the supercharger 10 is provided on the side of the motor 14 not connected to the intermediate shaft 16, and external fluid is taken in from this intake portion 10 b. A muffler, for example, is provided upstream of the suction portion 10 b.

The supercharger 10 of the present embodiment includes a cylindrical cover 30 surrounding the intermediate shaft 16 and the first joint 20 a. The cover 30 is formed in a substantially cylindrical shape and is configured to be dividable in the longitudinal direction. That is, the cover 30 is composed of an upper cover 30a shown in fig. 3 and 4 and a lower cover 30b shown in fig. 5 and 6. Further, a plurality of ribs 30c are provided on the outer peripheral side of the cylindrical surface formed of a thin plate so as to be vertical in the longitudinal direction on each of the upper cover 30a and the lower cover 30 b. At this time, as shown in fig. 1, the inner diameter of the cover 30 is larger than the outer diameter of the rotor 14a, and the inner diameter of the cover 30 is equal to or larger than the inner diameter of the stator 14 c. Further, the outer diameter of the shroud 30 is the same as the hub diameter of the impeller 12. The hub diameter is the outer diameter of the end of the hub 12d on the cover 30 side. One end of the cover 30 is fixed to a support member 14d disposed on the motor 14 side of the intermediate shaft 16. The cover 30 may be supported and fixed from the air guide tube 10 d. The cylindrical cover 30 need not entirely surround the intermediate shaft 16 in the longitudinal direction but partially surround it. The cylindrical cover 30 may be formed in a cylindrical shape or a polygonal cylindrical shape.

Next, the supercharger 10 of the present embodiment will be described in more detail.

As shown in fig. 1, the impeller 12 included in the compression portion 10a is attached to one end side of a drive shaft 18 extending along the axis X, and rotates about the axis X as the drive shaft 18 rotates about the axis X. A turbine (not shown) is attached to the other end side of the drive shaft 18 to which the impeller 12 is not attached. The drive shaft 18 rotates about the axis X as the turbine rotates about the axis X. That is, the impeller 12, the drive shaft 18, and the turbine integrally rotate about the axis X.

In the supercharger 10, exhaust gas discharged from the diesel engine rotates the turbine around the axis X. As the turbine rotates, the impeller 12 is rotated about the axis X by the drive shaft 18. When the impeller 12 rotates about the axis X, the fluid flowing in from the inlet 12a is compressed and discharged from the outlet 12 b. When the impeller 12 starts rotating around the axis X (compression start), negative pressure is generated near the suction port 12 a. By this negative pressure, the external fluid is sucked from the suction portion 10 b. That is, a fluid flow is formed from the suction portion 10b to the compression portion 10 a.

The flow of the fluid from the suction portion 10b to the compression portion 10a is roughly divided into a cooling air flow Fb flowing through the gap between the rotor 14a and the stator 14c, and a suction air flow Fa other than the cooling air flow Fb. The names of the flows of these fluids are for distinction, and for example, not only the cooling air flow Fb does not contribute to cooling the motor 14.

The suction air flow Fa is guided from the suction portion 10b to the suction port 12a of the impeller 12 after passing between the supports 14d (see fig. 2).

On the other hand, the cooling air flow Fb passes through the gap between the rotor 14a and the stator 14 c. The cooling air flow Fb passing through the gap takes heat of the motor 14 that generates heat, and as a result, cooling of the motor 14 is effected. The intake air flow Fa also acts to cool the motor 14 from outside the main body portion 14 b.

The cooling air flow Fb flowing out from the gap between the rotor 14a and the stator 14c is guided into the cover 30 surrounding the first joint 20a and the intermediate shaft 16. Further, inside the hood 30, the suction air flow Fa and the cooling air flow Fb do not interfere with each other. Further, the flow path area around the cover 30 is uniformly reduced in the flow direction of the fluid by the cover 30.

The cooling air flow Fb guided into the hood 30 flows out from the hood opening 30d near the suction port 12a where negative pressure is generated. The cooling airflow Fb thus discharged merges with the intake airflow Fa and is guided to the intake port 12 a.

The motor 14 may be a motor 14 that assists the supercharging capacity by rotating the impeller 12 with electric power when the diesel engine is operating at low output and the discharged exhaust gas is insufficient to supply the supercharger 10 with sufficient supercharging capacity, or may be a generator that generates electric power by rotating the rotor 14a via the drive shaft 18, the joint, and the intermediate shaft 16 connected to the turbine when the remaining exhaust gas is discharged from the diesel engine. The generator may be configured such that the motor 14 functions as a generator.

The supercharger 10 according to the present embodiment can exhibit the following effects.

Interference of the flows of the intake air flow Fa and the cooling air flow Fb with each other can be suppressed by the hood 30 on the outer side and the inner side of the hood 30. Further, the flow path area around the cover 30 can be reduced uniformly in the flow direction of the fluid. This arrangement rectifies the intake air flow Fa while reducing the pressure loss of the intake air flow Fa guided to the intake port 12a of the impeller 12, thereby preventing the intake air flow Fa from decelerating. Further, the flow rate of the suction air flow Fa guided to the suction port 12a of the impeller 12 can be sufficiently ensured. That is, the intake air flow Fa can be efficiently guided to the impeller 12.

At the same time, the cooling air flow Fb can be reliably guided into the motor 14 (the gap between the rotor 14a and the stator 14 c). This is because the cooling air flow Fb flowing out from the gap between the rotor 14a and the stator 14c is not interfered by the intake air flow Fa, and therefore, the flow of the cooling air flow Fb can be maintained. Further, since the inner diameter of the cover 30 is larger than the outer diameter of the rotor 14a and the inner diameter of the cover 30 is equal to or larger than the inner diameter of the stator 14c, the cooling air flow Fb flowing out from the gap between the rotor 14a and the stator 14c is less likely to be interfered with by the cover 30. Further, the cooling air flow Fb flowing out from the gap is guided into the cover 30, flows out from the cover opening 30d near the suction port 12a where negative pressure is generated, and merges with the suction air flow Fa. At this time, the outer diameter of the shroud 30 is the same as the hub diameter of the impeller 12. In the case where the outer diameter of the shroud 30 is larger than the hub diameter, the shroud 30 interferes with the intake air flow Fa. When the outer diameter of the cover 30 is smaller than the hub diameter, the cover opening 30d is excessively reduced, and the cooling air flow Fb cannot be efficiently guided to the vicinity of the suction port 12 a. These phenomena can be avoided as long as the outer diameter of the shroud 30 is the same as the hub diameter of the impeller 12. In this way, by bringing the hood opening 30d close to the suction port 12a where negative pressure is generated and efficiently guiding the cooling air flow Fb to the vicinity of the suction port 12a, the flow velocity of the cooling air flow Fb in the hood 30 can be maintained. As a result, the flow velocity of the cooling air flow Fb circulating in the gap between the rotor 14a and the stator 14c can be maintained. By these effects, the cooling performance of the motor 14 by the cooling air flow Fb can be improved. Thus, the output power can be increased without changing the model of the motor 14. Further, it is not necessary to additionally provide a cooling mechanism for cooling the motor 14, and cost reduction can be achieved.

If the cover 30 is not provided as a coupling structure in which the motor 14 and the inlet of the impeller 12 are separated from each other, the intake air flow Fa and the cooling air flow Fb interfere with each other and disturb each other, and thus the intake air flow Fa cannot be efficiently guided to the impeller 12 and the performance of the supercharger 10 is reduced, or the flow of the cooling air flow Fb cannot be maintained and the cooling performance of the motor 14 is reduced. Further, since the cooling air flow Fb merges with the intake air flow Fa at a position away from the vicinity of the suction port 12a where the negative pressure is generated, the differential pressure with the vicinity of the suction port 12a may be reduced, and the cooling air flow Fb may not be appropriately formed. Further, since the flow path area around the cover 30 is rapidly enlarged in the flow direction of the fluid, the performance of the supercharger 10 may be reduced by the pressure loss.

Further, by configuring the cover 30 to be dividable in the longitudinal direction, the assembling property of the cover 30 can be improved. The space for disposing the cover 30 must be dense not only for the upper support members 14d to move in and out of each other, but also for the motor 14, the intermediate shaft 16, and the like. However, when the cover 30 is divided into the upper cover 30a and the lower cover 30b, the cover 30 passing between the supports 14d can be reduced in size by half, and thus the entrance and exit are easy. For example, the lower cover 30b and the lower stay 14d are assembled in advance, and then the components constituting the motor 14, the intermediate shaft 16, and the like are provided. Finally, upper cover 30a and lower cover 30b fixed in advance are attached to each other, whereby the ease of assembly of cover 30 can be improved.

Further, by providing the ribs 30c in the longitudinal direction of the cover 30, even if the cover 30 has a thin-walled structure, the strength of the cover 30 can be ensured by the ribs 30c, and therefore, weight reduction can be achieved by making the cover 30 thin.

Description of the symbols

10 supercharger

10a compression part

10b suction part

10c housing

10d air guide cylinder

12 impeller

12a suction inlet

12b discharge port

12c blade

12d axle hub

14 motor

14a rotor

14b main body part

14c stator

14d support

14e bearing

16 intermediate shaft

18 drive shaft

20a first joint (Joint)

20b second joint (Joint)

30 cover

30a upper cover

30b lower cover

30c Rib

30d cover opening

Fa inhalation airflow

Fb cooling air flow