JPH0774612B2 - Turbocharger with rotating electric machine - Google Patents

Description

TECHNICAL FIELD The present invention relates to a turbocharger with a rotating electric machine.

[Conventional technology]

Turbochargers applied to engines of automobiles,
The exhaust gas energy of the engine is used as the drive source. Further, in the turbocharger, a rotor of a rotating electric machine (for example, a synchronous machine that also serves as a generator / motor) is provided on a rotating shaft that connects the turbine impeller and the compressor impeller, and the exhaust gas energy is converted into electric power according to the state of the engine. It has been proposed to selectively use the battery as a power source such as a battery or to drive it as an electric motor to assist the supercharging operation.

There are various types of structures of turbochargers with rotating electric machines. Among these, for example, JP-A-51-106816
JP-A-63-248920 and the like support a rotary shaft that directly connects the impellers of the turbine and the compressor with at least two bearings, and the rotor of the rotary electric machine on the rotary shaft is a bearing. Located in between.

However, in this method, since both ends of the housing (rotating electric machine chamber) that houses the rotating electric machine serve as bearing portions, the inner diameters of both ends of the housing are narrowed. Therefore, the inner diameter of both ends of the housing becomes smaller than the outer diameter of the rotor, and the rotor cannot be inserted into the housing from one end as it is. There was a problem in terms of productivity.

Therefore, usually, JP-A-62-254649 and JP-A-63-3021
No. 36, JP-A 64-45922 and U.S. Pat. No. 4253031, as disclosed in, between the turbine and the compressor,
The bearing portion supporting the rotating shafts of the turbine impeller and the compressor impeller and the rotating electrical machine room are arranged adjacent to each other, and the rotating shaft is inserted into the bearing portion and the rotating electrical machine room. A system in which a rotor of a rotating electric machine is mounted in an overhang state is adopted.

This overhang method eliminates the need to throttle one end of the housing that will be the rotating electrical machine room. Since the compressor impeller and the compressor impeller can be sequentially inserted into the rotary shaft, the assembly can be simplified. However, there were the following points to be improved.

[Problems to be Solved by the Invention]

Lubricating oil is supplied to the bearing portion that supports the rotary shaft of the turbocharger in order to prevent seizure of the bearing. In the conventional overhang system, in order to prevent the lubricating oil from entering the rotary electric machine chamber adjacent to the bearing portion and the compressor chamber adjacent to the bearing portion, a shaft seal is provided between the bearing portion and the rotary electric machine chamber.

According to such a shaft seal arrangement structure, the distance between the rotor and the bearing portion of the rotary electric machine is increased by the amount of the shaft seal, and the amount of overhang cannot be reduced. As a result, the burden on the bearing portion increases. Moreover, the larger the overhang, the greater the deflection and bending of the rotary shaft, and the greater the displacement of the compressor impeller at one end of the rotary shaft. Therefore, the clearance between the compressor impeller and its case must be increased, which is a negative factor for the compressor efficiency.

Further, this type of rotating electric machine is desired to be cooled, because the magnet is easily demagnetized by heat due to the thermal influence of the engine room and the turbine and the output is lowered. As a conventional cooling structure, as in U.S. Pat.No. 4253031, a compressor impeller is provided with a hole for guiding cooling air to the rotary electric machine room side. Compressor efficiency may decrease.

The present invention has been made in view of the above points, and an object of the present invention is to reduce the overhang amount of the rotating electric machine or eliminate the overhang while simplifying the assemblability, and further, to supply to the bearing portion. It is an object of the present invention to provide a rational turbocharger with a rotating electric machine that can also use the lubricating oil for cooling the rotating electric machine.

[Means for Solving the Problems]

In order to achieve the above object, the present invention basically proposes the following problem solving means.

In order to facilitate understanding of the contents of the present invention, the first basic problem solving means will be described below with reference to the reference numerals of the embodiment of FIG.
The second basic problem solving means will be described with reference to the reference numerals of the embodiment of FIG.

The first means for solving the problem is mainly concerned with the ease of assembling, the reduction of the overhang amount of the rotating electric machine and the cooling function, and the contents thereof are the respective impellers of the turbine and the supercharging compressor driven by the exhaust gas energy of the engine. 2, 3 are connected by a rotary shaft 7, a bearing portion 4 with an oil passage 18 for introducing lubricating oil and a rotary electric machine chamber 6 are arranged in parallel between the turbine and the compressor, and the bearing portion 4 and the rotary electric machine chamber 6 are penetrated. In a turbocharger in which a rotor 10 of a rotary electric machine is mounted in an overhang state on a portion of the rotary shaft 7 that extends from the bearing portion 4 to the rotary electric machine chamber 6, a back plate 14 is provided between the rotary electric machine chamber 6 and the compressor.
A bearing for supporting the rotary electric machine chamber 6 and the rotor 10 in an overhang state, by mounting the shaft seal portion 12 between the rotor 10 and the compressor while penetrating the rotary shaft 7 in the back plate 14. The structure is such that no shaft seal part is provided between the part 4 and the part 4.

The second means for solving the problem is mainly concerned with the simple combination, the elimination of the overhang of the rotating electric machine and the cooling function, and the contents thereof are the impellers 2 of the turbine and the supercharging compressor driven by the exhaust gas energy of the engine. , 3 are coupled by a rotary shaft 7, a rotary electric machine chamber 6 is arranged between the turbine and the compressor, and a rotor 10 in the rotary electric machine chamber is provided on the rotary shaft 7. A first bearing portion 4 having an oil passage 18 for introducing lubricating oil is provided between the two, and a back plate 14 is attached between the rotary electric machine chamber 6 and the compressor, and a second bearing portion 5 is attached to the back plate 14. Are provided to position the rotor 10 of the rotating electric machine between the first and second bearing portions 4 and 5, and the rotating shaft 7 is supported by these bearing portions 4 and 5, and the first bearing portion 4 There is no shaft between the rotating electrical machine rooms 6. Part of the lubricating oil enters the rotary electric machine chamber 6 from the side of the first bearing portion 4 without providing a ring portion, while the back plate 14 seals between the rotary electric machine chamber 6 and the compressor. The shaft seal portion 12-1 is provided.

[Action]

With such a configuration, in the turbocharger with an overhang type rotary electric machine, since there is no shaft seal portion between the rotary electric machine chamber 6 and the bearing portion 4 that supports the rotor 10 by the overhang, the rotary shaft The amount of overhang of the rotor 10 mounted on 7 is reduced.

Even if there is no shaft seal portion between the rotary electric machine chamber 6 and the bearing portion 4, the back plate 14 interposed between the rotary electric machine chamber 6 and the compressor and the shaft seal portion 12 attached thereto impairs the sealing performance. There is no.

According to the means for solving the problem, a part of the lubricating oil supplied to the bearing portion 4 positively enters the rotating electric machine chamber 6 side, but the lubricating oil entering the rotating electric machine chamber 6 is
The presence of the shaft seal portion 12 and the shaft seal portion 12 prevents the compressor from entering the compressor side. The lubricating oil that has entered the rotary electric machine chamber 6 is effectively used as a means for cooling the rotary electric machine elements such as the rotor.

Further, in the assembly of the turbocharger, when the rotor 10 and its accessory parts are attached to the rotary shaft 7 extending from the bearing portion 4 to the rotary electric machine chamber 6, the back plate 14 is removed in advance and the synchronous chamber 6 (housing 1B ) Can be sequentially installed from one end opening, and then the back plate can be attached, so that the assembling work can be kept simple.

Operation of Second Problem Solving Means ... In this problem solving means, the first bearing portion 4 and the second bearing portion 4 are provided on both sides of the rotor 10 of the rotating electric machine.
Since the bearing part 5 supports the rotating shaft 7, the overhang of the rotor 10 can be eliminated.

Further, even when the overhang method is not adopted, similar to the first problem solving means, parts such as the rotor 10 are sequentially assembled from one end of the opening of the housing 1B in a state where the back plate 14 is removed and the assembly is simplified. In the same manner as the first problem solving means, the rotating electric machine is cooled by using lubricating oil.

〔Example〕

 Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a vertical cross-sectional view showing a first embodiment of the present invention, in which 1 is a main body of a turbocharger, a turbine case (not shown) accommodating a turbine impeller 2 and a compressor case (according to the drawing) accommodating a compressor impeller 3. Omitted), a housing 1A provided with a bearing portion 4 (here, the bearing portion 4 is composed of radial bearings 4A, 4B, and a thrust bearing 4C), a chamber 6 of a rotating electric machine (a synchronous machine that is a generator / motor combined in this embodiment). And a center housing 1B having

A housing 1A (bearing portion) and a center housing 1B (rotary electric machine chamber 6) are arranged in this order from the turbine side between the turbine case and the compressor case.
The rotary shaft 7 penetrates through the centers of 1A and the center housing 1B.

The turbine impeller 2 is attached to one end of the rotating shaft 7, and the compressor impeller 3 is attached to the other end.

The turbine impeller 2 is driven by engine exhaust gas guided into the turbine case, and the supercharged intake air of the compressor impeller 3 is supplied to the engine via an intake system of the engine.

A shaft through hole 8 is formed in the center of the housing 1A, and two radial bearings 4A and 4B are arranged at both ends of the shaft through hole 8. The rotary shaft 7 passing through the shaft through hole 8 is a radial bearing 4A. ,Four
It is supported by B and is further supported via a thrust bearing 4C provided next to the radial bearing 4B.

Radial bearings 4A, 4B and thrust bearing 4 in this embodiment
C consists of a metal bearing.

In the portion of the rotary shaft 7 extending from the bearing portion 4 (radial bearings 4A, 4B, thrust bearing 4C), the rotor 10 of the rotating electric machine and the seat ring are sequentially arranged from the bearing portion 4 toward the compressor.
15, the spacer 11 is arranged, and the compressor impeller 3 is further attached.

The seat ring 15 is in contact with the shaft seal portion 12 described below.

Here, the mounting structure of the shaft seal portion 12 will be described.

The center housing 1B has a rotary electric machine chamber 6 inside, is a hollow cylinder, and a stator 13 of the rotary electric machine is fixedly arranged on the inner wall thereof, and a rotor (field rotor) including a magnet 10A and a cover 10B on the rotary shaft 7 side. 10 is installed. Further, one end of the rotating electric machine chamber 6 is closed by a side wall of the housing 1A, and a disk-shaped back plate 14 is attached to the other end by screwing. It is separated from the impeller 3 accommodating portion).

A through hole for the rotary shaft 7 is formed in the center of the back plate 14, and the spacer 11 is located in this through portion. Further, the shaft seal portion 12 is press-fitted in the center of the back plate 14 so as to surround the spacer 11.

In this embodiment, a mechanical seal is used as the shaft seal portion 12, and its details are shown in FIG.

As shown in FIG. 4, in the mechanical seal 12, the packing 12b is brought into pressure contact with the seat ring 15 by the spring 12a to axially seal the rotary electric machine 6 and the compressor.

Reference numeral 16 denotes a turbine side shaft seal portion which is located between the radial bearing 4A and the turbine impeller 2 and is provided with a housing.
It is interposed between the inside of 1A and the outer circumference of the rotary shaft 7.

The housing 1A is provided with a passage 17 for introducing a part of engine cooling water and an oil passage 18 for supplying a part of the engine oil as lubricating oil to the radial bearings 4A, 4B and the thrust bearing 4C. An oil drain hole 19 is provided to connect the downstream side of the oil passage 18 (downstream side with respect to the bearing portion 4) and the lower portion of the rotary electric machine chamber 6.

Here, the assembly of the turbocharger of this embodiment will be described.

In the shaft insertion portion 8 of the housing 1A, the radial bearings 4A, 4
B and thrust bearing 4C are mounted, and housing 1A and center housing 1B are joined together. Then, with the turbine impeller 2 attached to one end of the rotary shaft 7,
The other end is inserted from the turbine side through the inside of the housing 1A and the center housing 1B (rotary electric machine chamber 6) to reach the compressor side.

Next, in the portion of the rotary shaft 7 extending from the thrust bearing 4C to the rotary electric machine chamber 6, the rotor 1 is sequentially arranged from the thrust bearing 4C side.
0, the seat ring 15 is fitted. In this case, the rotary shaft 7 has a multi-stage shape in advance, and the thrust bearing 4C is positioned by one of the stepped portions 7a, and the rotor 10, the seat ring 15, the spacer 11, etc. are naturally positioned with reference to this. After fitting the rotor 10, the seat ring 15, etc., the back plate 14 with the shaft seal portion 12 is attached so as to close the one end opening of the center housing 1B, and then the spacer is provided adjacent to the seat ring 15 of the rotary shaft 7. 11 and compressor impeller 3 are attached. Then, the turbine case and the compressor case are attached.

With such a configuration, the shaft seal portion 12 is located on the compressor side with respect to the rotor 10 of the rotary electric machine, and the shaft seal portion exists between the rotary electric machine chamber 6 and the bearing portion 4. Since the rotor 10 is not provided, the rotor 10 can be provided immediately adjacent to the thrust bearing 4C, and the amount of overhang of the rotor 10 becomes smaller than in the conventional case. FIG. 3A shows a rotor 10 of this embodiment.
Fig. 3 (b) shows the amount of overhang of the conventional rotor 10
Indicates the overhang amount of. As in the conventional example shown in FIG. 3 (b), the shaft seal portion 1 is provided between the rotor 10 and the thrust bearing 4C.
In this embodiment, the amount of overhang of the rotor 10 is reduced as compared with the case where 2'is located. To that extent, it is possible to suppress the deflection and bending of the rotary shaft 7 on the compressor impeller side. As a result, the clearance between the compressor impeller 3 and the inner circumference of the compressor case can be reduced,
The compressor efficiency can be improved.

In addition, the load on the bearing portion 4 can be reduced and the reliability of the bearing portion can be improved.

A part of the engine oil is circulated and supplied to the radial bearings 4A, 4B and the thrust bearing 4C via an oil passage 18.

FIG. 2 shows the flow of lubricating oil. As shown by the arrows in FIG. 2, a part of the lubricating oil supplied to the radial bearings 4A, 4B and the thrust bearing 4C enters the rotary electric machine chamber 6 and the rotary shaft 7
Scattered by the centrifugal force of. This lubricating oil directly cools the rotor 10 of the rotating electric machine, and the magnet 10A of the rotor 10 is cooled.
Prevents heat from being demagnetized. The lubricating oil that has entered the rotating electric machine chamber 6 flows down to the bottom of the rotating electric machine chamber 6 after cooling the rotor 10, and passes through the drain hole 19 to the oil passage 18
To join. The presence of the shaft seal portion 12 prevents the lubricating oil from flowing out to the compressor side.

As described above, according to the present embodiment, while maintaining the ease of assembly of the turbocharger, the amount of overhang of the rotor 10 of the rotating electric machine is reduced to improve the efficiency of the turbocharger and the reliability of the bearing. Moreover, it is possible to rationally cool the rotating electric machine by utilizing the lubricating oil.

Further, the oil passage 18 formed in the housing 1A can be of the same structure as the conventional one, and it is not necessary to design a new one.

Further, in the past, as shown in FIG. 3 (b), a thrust bearing was used.
Although the shaft seal portion 12 'was provided immediately adjacent to 4C, the pressure in the vicinity of the thrust bearing 4C is higher than that in the rotary electric machine chamber 6 due to the influence of the oil pressure in the oil passage 18. Therefore, the lubricating oil easily leaks to the center housing 1B and then the compressor side. In order to solve such a problem, it is necessary to provide an auxiliary shaft seal portion between the rotary electric machine chamber 6 and the compressor 3 in addition to the shaft seal portion 12 '.

On the other hand, according to the shaft seal structure of the present embodiment, invasion of lubricating oil from the thrust bearing 4C into the rotary electric machine chamber 6 is positively accepted for cooling, and sealing is performed on the compressor side.

By doing so, the oil pressure of the lubricating oil is once reduced in the rotary electric machine chamber 6, and the lubricating oil is scattered in the centrifugal direction by the rotation of the rotor 10, so that the shaft seal portion 12 is satisfied at one place. There is an advantage that can be.

FIG. 5 and FIG. 6 show a second embodiment of the present invention. The same symbols as those in the first embodiment are the same or common elements.

In this embodiment, a seal ring 12-1 is used as a shaft seal portion on the back plate 14. Seal ring 12-
1 is interposed between the outer circumference of the spacer 11 and the inner circumference of the back plate 14.

In addition to the above, for example, a labyrinth seal 12-2 as shown in FIG. 7 may be used as the shaft seal portion, and the type thereof is not limited.

FIG. 8 shows a third embodiment of the present invention.

In this embodiment, the radial bearings 4A and 4B arranged in the same manner as the above-mentioned embodiments are used as the first bearing portion 4. In addition, the thrust bearing 5 is attached to the back plate 14 arranged between the housing 1B and the compressor, and this is used as the second bearing portion.
Since the thrust bearing 5 has the above arrangement structure, the oil passage
A part of 18 is branched and a branch passage 20 is formed from the housing 1A to the center housing 1B so that the lubricating oil is directly supplied to the thrust bearing 5.

According to this structure, the first bearing portion 4 and the second bearing portion 5 are located at both ends of the rotor 10, so that the overhang of the rotor 10 is eliminated. Further, the rotor 10 and the like are incorporated and the lubricating oil is cooled in substantially the same manner as in the first embodiment. The second bearing portion 5 may be a radial bearing.

FIG. 9 shows a fourth embodiment of the present invention.

In this embodiment, the arrangement structure of the shaft seal portion 12 is the first
This embodiment is similar to the embodiment, except that two ball bearings 21 and 22 are used as bearings of the rotary shaft 7, and the ball bearings 21 and 22 serve as both radial bearings and thrust bearings. .

FIG. 10 shows a fifth embodiment of the present invention.

In this embodiment, the arrangement structure of the shaft seal portion 12 is similar to that of the first embodiment, except that the oil passage 18 is branched and a part of the lubricating oil is positively rotated by the branch passage 23. An orifice 24 is provided which leads into the electric machine room 6 and narrows the outlet side of the divided passage 23.

With such a composition, the lubricating oil guided through the branch passage 23 blows out into the center housing 1B through the orifice 24. Therefore, there is an advantage that it is possible to cool the rotating electric machines of the above-described respective embodiments.

〔The invention's effect〕

As described above, according to the present invention, in the first problem solving means, when the overhang method excellent in assembling property is adopted, (a) while maintaining the easiness of assembling, the (b) shaft seal part is provided. By arranging it between the rotating electrical machine room and the compressor, the amount of overhang of the rotating electrical machine can be reduced, which in turn can improve the reliability of the bearing part and the compressor efficiency. Can be used to effectively cool the rotating electric machine and prevent a decrease in the output of the rotating electric machine.

In addition to the above (a) and (c), the second problem solving means has an effect of eliminating an overhang.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment of the present invention, FIG. 2 is an explanatory view showing a flow state of lubricating oil thereof, and FIGS. 3 (a) and 3 (b) are the first embodiment. FIG. 4 is an explanatory view comparing the overhang amounts of the rotors of the example and the conventional example, FIG. 4 is a sectional view of a main part showing a part of the first embodiment, and FIG. 5 is a longitudinal section showing a second embodiment of the present invention. FIG. 6 is a cross-sectional view showing a part of a main portion showing a part thereof, FIG. 7 is a cross-sectional view showing another embodiment of the shaft seal portion used in the present invention, and FIGS. It is a longitudinal section showing each of the 3rd example-the 5th example of. 1 (1A, 1B) ... turbocharger body, 1A ... housing, 1B ... center housing, 2 ... turbine impeller, 3 ... compressor impeller, 4 ... bearing section (1st)
Bearing part), 4A, 4B ... radial bearing, 4C ... thrust bearing, 5 ... second bearing part, 6 ... rotating electric machine room, 7 ...
Rotating shaft, 10 ... Rotor (field rotor), 12,12-1,12-
2 …… Shaft seal part, 14 …… Back plate, 15 …… Seat ring, 18 …… Oil passage, 19 …… Oil drain,
21A, 21B …… Ball bearing, 23 …… Branch passage, 24 …… Orifice.

Claims (9)

[Claims] 1. A bearing section with an oil passage for introducing lubricating oil between a turbine and a compressor, which uses an exhaust gas energy of an engine as a drive source, and an impeller of a compressor for supercharging, and a rotary electric machine room. In a turbocharger in which the rotor of the rotating electric machine is mounted in an overhang state on a portion of the rotary shaft penetrating the bearing portion and the rotating electric machine chamber, the rotor protruding from the bearing portion to the rotating electric machine chamber. A back plate is attached between the chamber and the compressor, and a shaft seal portion is provided between the rotor and the compressor while penetrating the rotary shaft through the back plate, while the rotary electric machine chamber and the rotor are overhung. A turbocharger with a rotating electric machine, characterized in that a shaft seal portion is not provided between the bearing portion supported by Ah. 2. The turbocharger with a rotating electric machine according to claim 1, wherein the bearing portion comprises two radial bearings and one thrust bearing. 3. The turbocharger with a rotating electric machine according to claim 1, wherein the bearing portion comprises two ball bearings. 4. A rotary electric machine chamber is arranged between the turbine and compressor by connecting respective impellers of a turbine and a supercharging compressor driven by exhaust gas energy of an engine by a rotary shaft. In a turbocharger having a child on the rotary shaft, a first bearing portion having an oil passage for introducing lubricating oil is provided between the turbine and the rotary electric machine chamber, while the rotary electric machine chamber,
A back plate is attached between the compressors, a second bearing portion is provided on the back plate, and the rotor of the rotary electric machine is positioned between the first and second bearing portions, and the rotary shaft is provided by these bearing portions. And a shaft seal portion is not provided between the first bearing portion and the rotary electric machine chamber, and a part of the lubricating oil enters the rotary electric machine chamber from the first bearing portion side. A turbocharger with a rotary electric machine, wherein the back plate is provided with a shaft seal portion for sealing between the rotary electric machine chamber and the compressor. 5. The fourth bearing according to claim 4, wherein the first bearing portion is a radial bearing portion, the second bearing portion is a thrust bearing portion, and the second thrust bearing portion is the first bearing portion. A turbocharger with a rotating electric machine in which the oil passage is branched to supply lubricating oil. 6. Any one of claims 1 to 5
Paragraph 3. A turbocharger with a rotating electric machine, wherein an oil drain hole communicating with the oil passage is provided in a lower portion of the rotating electric machine chamber. 7. The invention according to any one of claims 1 to 6.
In the paragraph, the turbocharger with a rotating electric machine is provided with a passage for branching a part of the oil passage before reaching the bearing portion and guiding a part of the lubricating oil as cooling oil to the rotating electric machine chamber. 8. The turbocharger with a rotating electric machine according to claim 7, wherein the passage for introducing the cooling oil into the rotating electric machine chamber is provided with an orifice formed at the passage outlet so that the orifice is formed so as to blow the cooling oil into the rotating electric machine chamber. 9. A method according to any one of claims 1 to 8.
In the paragraph, the shaft seal portion is a turbocharger with a rotating electric machine, which is formed of any one of a mechanical seal, a seal ring, and a labyrinth seal.