JPH11101128A - Super charger, method for assembling thereof and bearing unit used in supercharger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a supercharge which can be simply assembled. SOLUTION: In a supercharger in which a turbine shaft 2 integrally incorporated at its one end with turbine blades 3 and mounted at its the other end with compressor blades 4 is rotatably journalled at its intermediate part in a through hole 7 in a housing 1 through the intermediary of a bearing unit 8, the through hole 7 is formed in such a shape that the turbine shaft 2 which is fitted thereon with the bearing unit 8 but is not yet fitted thereon with the compressor blades 4 can be inserted in the through-hole 7 through an opening on the turbine chamber 5 side thereof. That is, in such a condition that the bearing unit 8 is fitted on the turbine shaft 2 in the housing 1, the turbine shaft 2 can be fitted in the housing, thereby it is possible to simply and rapidly assemble the supercharger.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a supercharger, a method for assembling the same, and a bearing unit that can be used for the supercharger. Examples of the supercharger include a so-called turbocharger and a supercharger.

[0002]

2. Description of the Related Art In a turbocharger, a turbine shaft rotating at a high speed of, for example, 100,000 rpm or more is supported by a housing using a sliding bearing such as a floating metal, or disclosed in Japanese Utility Model Publication No. 2-45477. As a result, a form in which the housing is supported via a bearing unit having two angular ball bearings has been considered.

[0003] In the case where the bearing unit is used as described above, the rotation characteristics of the turbine shaft are superior to the case where the plain bearing is used.

In the turbocharger disclosed in the above publication, the turbine shaft is inserted into the insertion hole of the housing from the turbine chamber side, and the turbine unit is inserted into the insertion hole from the opening on the compressor chamber side. Externally fitted to the shaft in a loose fit state. Thereafter, the mechanical seal spacer and the compressor blade are mounted on the free end side of the turbine shaft. Thereafter, a retaining plate is screwed into the opening of the insertion hole on the compressor chamber side.

[0005]

However, it is pointed out that the above-mentioned conventional turbocharger is extremely troublesome in the assembly operation, as described above, in that the turbine shaft and the bearing unit must be incorporated separately. Is done. Because of this configuration, the balance must be adjusted as a whole with the turbine shaft and bearing unit installed in the insertion hole.If the balance is poor, remove the assembly and adjust the balance again. The assembly efficiency is extremely poor, such as having to reassemble after reassembling, or damaging the shaft, bearings, etc. due to the press-fit of the inner ring at the time of disassembly. . For this reason, the production cost has been increased due to poor productivity and the like.

Accordingly, the present invention provides a turbocharger
It is intended to have a structure that allows easy assembly work.

[0007]

According to a first aspect of the present invention, there is provided a turbocharger having a turbine blade integrally formed at one end thereof and a compressor shaft mounted at the other end thereof. The insertion hole is rotatably supported by the insertion hole, and the insertion hole is formed from the turbine chamber side opening thereof into a shape into which a turbine shaft on which a bearing unit is mounted and a compressor blade is not mounted can be incorporated.

In the second supercharger of the present invention, an intermediate region of a turbine shaft in which a turbine blade is integrally formed at one end and a compressor blade is mounted at the other end is rotatable through a bearing unit into an insertion hole of a housing. The insertion hole is formed from the turbine chamber side opening thereof into a shape in which a bearing unit is mounted and a turbine shaft to which a compressor blade is not mounted is incorporated, and the insertion hole is formed on the turbine blade side of the turbine shaft. A bulging portion that forms a minute opposing gap is formed between the insertion hole and the inner peripheral surface of the turbine chamber side opening.

The third supercharger according to the present invention comprises the first and second superchargers.
In the turbocharger described above, the turbine chamber side opening of the insertion hole that forms the opposing gap with the bulging portion is enlarged, and the inner diameter of the enlarged diameter portion is smaller than the inner diameter of the bearing unit mounting area of the insertion hole. Body is worn.

The method for assembling a supercharger according to the present invention is characterized in that
In the configuration of the second supercharger, the bearing unit is mounted on the turbine shaft, the compressor blade is not mounted, and the turbine shaft is installed from the turbine chamber side opening of the insertion hole,
A compressor blade is attached to a free end of the turbine shaft projecting from the opening of the through hole in the compressor chamber.

[0011] The first bearing unit of the present invention comprises the first bearing unit.
To the third supercharger, which are mounted respectively at two locations separated in the axial direction in an intermediate region of the turbine shaft, the turbine shaft is an inner ring, and the outer diameter of the outer ring is the same as the outer diameter of the bulging portion. Alternatively, the rolling bearing includes a rolling bearing set to be small, and biasing means provided between the rolling bearings to resiliently bias the outer races of the rolling bearings in a direction of separating them from each other.

[0012] The second bearing unit of the present invention comprises the first bearing unit.
To the third supercharger, which are mounted respectively at two locations separated in the axial direction in an intermediate region of the turbine shaft, the turbine shaft is an inner ring, and the outer diameter of the outer ring is the same as the outer diameter of the bulging portion. Alternatively, a small-sized rolling bearing, a biasing means provided between the two rolling bearings to resiliently bias the outer rings of the two rolling bearings in a direction to separate them from each other, and the both outer rings provided between the two rolling bearings And a spacer that regulates the amount of axial displacement.

In the above-described turbocharger or the method of assembling the turbocharger according to the present invention, the turbine shaft having the bearing unit exterior and the compressor blades not mounted thereon can be incorporated from the opening of the insertion hole on the turbine chamber side. Therefore, assembling can be performed easily and quickly as compared with the conventional example. For this reason, before installing the turbine shaft into the insertion hole, the balance can be adjusted with the bearing unit and the compressor blade mounted on the turbine shaft outside, and the balance adjustment can be performed very easily and quickly. become.

Further, in the bearing unit of the turbocharger of the present invention, since the inner ring is not used, the outer diameter of the turbine shaft can be increased or the outer diameter of the bearing unit can be reduced accordingly. In the former case, the rigidity of the turbine shaft can be increased, and in the latter case, it is possible to contribute to downsizing.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the embodiments shown in FIGS.

FIGS. 1 to 5 relate to an embodiment of the present invention. FIG. 1 is a sectional view of a main part of a supercharger, and FIG. 2 is a sectional view taken along a line (2)-(2) in FIG. FIG. 3 is an explanatory view showing a procedure for mounting the bearing unit on the turbine shaft, and FIG.
FIG. 5 is an explanatory diagram showing a procedure for mounting the turbine shaft on the housing, and FIG. 5 is an explanatory diagram showing a procedure for mounting the compressor blade on the turbine shaft mounted on the housing.

In FIG. 1, reference numeral 1 denotes a housing, and 2 denotes a turbine shaft. A turbine blade 3 is integrally formed at one end of the turbine shaft 2, and a compressor blade 4 is mounted at the other end of the turbine shaft 2. The housing 1 is provided with an insertion hole 7 for communicating the turbine chamber 5 and the compressor chamber 6, and the intermediate region of the turbine shaft 2 is rotatably supported in the insertion hole 7 via a bearing unit 8. .

The insertion hole 7 is formed substantially flush with the axial direction except that a circumferential groove 9 is provided on the turbine chamber 5 side.

On the turbine blade 3 side of the turbine shaft 2, a bulging portion 10 is provided which forms a small opposing gap between the insertion hole 7 and the inner peripheral surface of the opening on the turbine chamber side. , Counter bores 11 having slightly larger diameters are provided at both ends in the axial direction of a region where the bearing unit 8 is mounted. An oil groove 12 is formed in the bulging portion 10, and the oil groove 12 is formed in the bearing unit 8.
The lubricating oil supplied to the turbine is splashed toward the peripheral groove 9 of the insertion hole 7 to prevent leakage to the turbine chamber 5 side. The bulging portion 10 has a C-shaped seal ring 1.
There is provided a circumferential groove 13 into which the play 4 is loosely fitted. The seal ring 14 has a play in the axial direction with respect to the circumferential groove 13 and floats from the groove bottom.
The outer peripheral surface is pressed against the inner peripheral surface of the above-described opening of the insertion hole 7 on the turbine chamber side, and is ideally designed to be non-rotating and not to cause sliding contact. That is, non-contact so-called labyrinth is caused by the opposing gap between the outer peripheral surface of the bulging portion 10 and the inner peripheral surface of the insertion hole 7 and the opposing gap between the inner wall surface of the peripheral groove 13 and the groove bottom and the seal ring 14. A seal is formed.

The bearing unit 8 includes two deep groove ball bearings 20A and 20B without an inner ring and two cases 21A and 21B.
B, a coil spring 22, and a spacer 23 formed of an annular body having a substantially C-shaped cross section. Deep groove ball bearing 20
Reference numerals A and 20B denote outer peripheral surfaces of an intermediate region in the axial direction of the turbine shaft 2 as inner rings, and outer rings 24A and 24B and a plurality of balls 2.
5A and 25B, and retainers 26A and 26B.
The inner diameters of the two cases 21A, 21B are approximately half in the axial direction.
B is provided, and the above-described deep groove ball bearings 20A, 20B are fitted inside the enlarged diameter portions 27A, 27B. In addition, flanges 28A and 28B projecting radially inward are provided substantially at the center in the axial direction of the cases 21A and 21B. Have been. By the resilient force of the coil spring 22, the outer races 24A and 24B are resiliently urged in a direction in which the outer races 24A and 24B are pulled apart from each other, so that the balls 25A and
Reference numeral 25B obliquely contacts the raceway grooves of the outer rings 24A, 24B and the raceway groove of the turbine shaft 2. At this time, the radial gap is controlled so that the contact angle between the balls 25A and 25B is, for example, 15 ° ± 5 °. Spacer 23
Is fitted in the turbine shaft 2 from the radial direction and is interposed between the two cases 21A and 21B. As shown in FIG. The pin 29 is prevented from rotating by a pin 30 and is positioned in the axial direction.

The bearing unit 8 is inserted into the insertion hole 7.
In the state in which the oil film damper is incorporated, a minute opposing gap that forms an oil film damper is formed between the outer peripheral surfaces of the cases 21A and 21B and the inner peripheral surface of the insertion hole 7. In other words, lubricating oil is supplied to the opposed gap via an oil supply passage 31 provided in the housing 1, and this lubricating oil functions as a damper for attenuating the vibration of the turbine shaft 2.
Further, the above-described lubricating oil is supplied from two small groove ball bearings 20A, 2A through small holes 32, 32 provided in the cases 21A, 21B.
After being supplied to OB for lubrication and cooling, it is discharged from a discharge passage 33 provided in the housing 1.

Next, the procedure for assembling the above-described supercharger will be described.

First, the bearing unit 8 is mounted on the turbine shaft 2. That is, as shown in FIG. 3A, the ball 25A is incorporated in the pocket of the retainer 26A,
As shown in the figure, the outer ring 24A of the deep groove type ball bearing 20A is mounted on one of these outer circumferences from one side in the axial direction, and a case 21A, a coil spring 22, a case 21B,
The outer ring 24B and the retainer 26B of the deep groove type ball bearing 20B are sequentially fitted, and the balls 25B are stored in respective pockets (illustration, reference numerals are omitted) of the retainer 26B.
As shown in FIG. 3, the outer ring 24B is attached, and as shown in FIG. 3C, the case 21B is attached to the outer ring 24B. Thereafter, as shown in FIGS. 3D and 3E, the spacer 23 is mounted from the region between the two cases 21A and 21B from the radial outside of the turbine shaft 2.

After the bearing unit 8 is mounted on the turbine shaft 2 in this way, the preliminary balance of the turbine shaft 2 is adjusted with the mechanical seal spacer 15 and the compressor blade 4 mounted on the free end side of the turbine shaft 2. Do.

After the preliminary balance adjustment is completed, the oil drain ring 15 and the compressor blade 4 are once removed from the turbine shaft 2 and are incorporated into the insertion hole 7. That is, as shown in FIG. 4, after inserting the turbine shaft 2 through the opening of the insertion hole 7 on the turbine chamber 5 side, the spacer 23 and the insertion hole 7 are inserted.
The pin 30 is inserted into the groove 29 and the turbine shaft 2 and the housing 1 are fixed. Next, as shown in FIG. 5, on the compressor chamber 6 side, the mechanical seal spacer 15 and the compressor blade 4 are fitted to the free end side of the turbine shaft 2 protruding from the insertion hole 7, and fixed with the nut 34. The stop plates 16 and 17 are screwed to the housing 1. Finally, the balance is finally adjusted in a state where the turbine shaft 2 is incorporated in the housing 1, and the turbine shaft 2 is completed.

As described above, the turbine shaft 2 on which the bearing unit 8 is mounted in advance is inserted into the insertion hole 7 of the housing 1 from one direction, and the remaining accessory parts are mounted on the turbine shaft 2 only. Since the assembling is completed, the assembling can be performed very easily and efficiently as compared with the conventional example. Moreover, before the turbine shaft 2 is incorporated into the insertion hole 7, the preliminary balance can be adjusted externally with the bearing unit 8 and accessories attached to the turbine shaft 2, so that the final balance adjustment can be performed very quickly and easily. Will be able to do it. The preliminary balance adjustment can be omitted. As a result, the assembly efficiency can be improved and the production cost can be reduced. In addition, since the deep groove ball bearings 20A, 20B of the bearing unit 8 have a structure without an inner ring, the deep groove ball bearings 20A, 20B
When the outer diameter of 0B is set to be the same as the conventional one, the outer diameter of the intermediate region in the axial direction of the turbine shaft 2 can be made larger than that of the conventional one, and the rigidity can be improved. .

In the above-described embodiment, since the deep groove type ball bearings 20A and 20B of the bearing unit 8 have no inner ring, a change in interference due to thermal expansion with the turbine shaft 2 can be ignored. The turbine shaft 2 can be formed of ceramics. As a result, a reduction in weight can be achieved, and effects such as a good response to rising at high speed rotation can be obtained. In this connection, the mechanical seal spacer 15 mounted on the turbine shaft 2 can be formed of ceramics, and the compressor blade 4 and the nut 34 can be formed of heat-resistant synthetic resin. In other words, by making the turbine shaft 2 made of ceramics, it is possible to suppress the temperature rise and the heat conduction, so that the above-mentioned materials can be selected. For this reason, the weight reduction of all these assembly structures can also be achieved, and it can contribute to the further improvement of rotation characteristics.

It should be noted that the present invention is not limited to only the above-described embodiment, and various applications and modifications are conceivable.

(1) In the above embodiment, for example, a supercharger of an automobile engine is taken as an example, but the form of the supercharger is not particularly limited.

(2) In the above embodiment, the bulging portion 1
0 and the opening of the through hole 7 on the turbine chamber side, the circumferential groove 13 of the bulging portion 10 and the seal ring 14.
Is preferably set to be larger than the facing gap for the oil film damper provided between the insertion hole 7 and the bearing unit 8. In this case, even if the rotational runout of the turbine shaft 2 becomes large, the bulging portion 1
0 can be prevented from colliding with the insertion hole 7 or the seal ring 14 colliding against the bottom of the circumferential groove 13 of the bulging portion 10. However, although there is a possibility that the cases 21A and 21B of the bearing unit 8 and the inner peripheral surface of the insertion hole 7 may collide with each other, since the oil film damper exists here and the collision is not directly performed, There is almost no rotation loss. Thereby, the turbine shaft 2
Can be improved as much as possible.

(3) As shown in FIG.
In this case, the opening of the through hole 7 on the turbine chamber side may be made large in diameter, and an annular plate 35 of the same material (for example, sintered metal) as the housing 1 may be fixed to this large diameter part by press fitting or the like. In this case, the inner diameter of the annular plate 35 and the outer diameter of the bulging portion 10 of the turbine shaft 2 can be set smaller than the inner diameter of the insertion hole 7. If the outer diameter of the bulging portion 10 can be reduced in this manner, the peripheral speed of the sliding portion can be reduced even in a situation where the circumferential groove 13 of the bulging portion 10 and the seal ring 14 are in sliding contact with each other. Performance can be improved.

(4) FIG. 7 is an enlarged view of a main part of FIG. 1 according to another embodiment of the present invention. In this embodiment, the configuration of the bearing unit 8 is different from the above embodiment.
The bearing unit 8 in this embodiment uses deep groove ball bearings 20A and 20B with inner and outer rings, mounts them on a single case 21, and also includes both deep groove ball bearings 20A and 20B.
A spacer 40 for defining the interval between the inner rings of 20B is mounted, and the spacer 23 in the above embodiment is omitted. In this case, it is necessary to make the outer diameter of the intermediate region in the axial direction of the turbine shaft 2 smaller than that of the above-described embodiment, but since it is almost the same as that of the conventional product, there is no problem in strength. In such an embodiment, assembling of the bearing unit 8 to the turbine shaft 2 can be more easily performed than in the above-described embodiment, so that the productivity is excellent.

(5) In the embodiment of FIG. 3, one of the ball bearings is assembled, and then the other ball bearing is assembled. Instead, the retainers 26A, 26
B, the outer rings 24A, 24B, the cases 21A, 21B, and the coil spring 22 are previously assembled, and the outer rings 24A, 24B
B, with the cases 21A and 21B retracted to the center with the coil spring 22 contracted, the balls 25A and
After the assembly of the bearing units 25B simultaneously, the outer rings 24A and 24B and the cases 21A and 21B may be spread outward by the urging force of the coil spring 22 to complete the bearing unit.

[0034]

According to the turbocharger and the method of assembling the turbocharger according to the first to fourth aspects of the present invention, a turbine shaft integrated with a bearing unit is provided through an opening of a through hole of a housing on a turbine chamber side. Since the device is designed so that it can be incorporated with one touch, the work can be performed easily and quickly as compared with the conventional example. Since such an assembly work can be performed,
Before installing the turbine shaft into the through hole of the housing, balance adjustment can be performed with the bearing unit and compressor blade mounted on the turbine shaft outside, so that balance adjustment can be performed very easily and quickly. Become. As a result, according to the present invention, as a result, it is possible to greatly contribute to improving the productivity of the turbocharger and reducing the manufacturing cost.

In the bearing unit for the turbocharger according to the fifth and sixth aspects of the present invention, since the inner ring is not used, the outer diameter of the turbine shaft is increased or the outer diameter of the bearing unit is increased. The diameter can be reduced, and in the former case, the rigidity of the turbine shaft can be increased, and in the latter case, the effect of contributing to downsizing can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a turbocharger according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line (2)-(2) of FIG.

FIG. 3 is an explanatory diagram showing a procedure for mounting the bearing unit on the turbine shaft in the embodiment.

FIG. 4 is an explanatory diagram showing a procedure for mounting the turbine shaft on the housing in the embodiment.

FIG. 5 is an explanatory diagram showing a procedure for mounting a compressor blade on a turbine shaft mounted on a housing in the embodiment.

FIG. 6 is an enlarged view of a main part corresponding to FIG. 1 in another embodiment of the present invention.

FIG. 7 is a view corresponding to FIG. 1 in still another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Housing 2 Turbine shaft 3 Turbine blade 4 Compressor blade 5 Turbine room 6 Compressor room 7 Housing insertion hole 8 Bearing unit 10 Turbine shaft bulging part 20A, 20B Deep groove ball bearing of bearing unit 21A, 21B Bearing unit case 22 Coil spring of bearing unit 24A, 24B Outer ring of deep groove ball bearing 25A, 25B Ball of deep groove ball bearing 26A, 26B Cage of deep groove ball bearing

Claims (6)

[Claims] 1. A turbocharger having a turbine blade integrally formed at one end and a compressor shaft mounted at the other end rotatably supporting an intermediate region of a turbine shaft in an insertion hole of a housing via a bearing unit. A turbocharger, wherein the insertion hole is formed from a turbine chamber side opening thereof into a shape into which a turbine shaft on which a bearing unit is mounted and a compressor blade is not mounted can be incorporated. 2. A turbocharger having a turbine blade integrally formed at one end and a compressor shaft mounted at the other end rotatably supporting an intermediate region of a turbine shaft in a through hole of a housing via a bearing unit, The insertion hole is formed from a turbine chamber side opening thereof into a shape into which a turbine shaft on which a bearing unit is mounted and a compressor blade is not mounted can be incorporated, and a turbine chamber of the insertion hole is provided on a turbine blade side of the turbine shaft. A supercharger, wherein a bulging portion that forms a minute facing gap is formed between the side opening and the inner peripheral surface. 3. The turbocharger according to claim 1, wherein an opening of the through hole that forms an opposing gap with the bulging portion has an enlarged diameter on the turbine chamber side, and the enlarged diameter portion has an inner diameter. Wherein a ring body smaller than the inner diameter of the bearing unit mounting area of the insertion hole is mounted. 4. A method for assembling a supercharger according to claim 1, wherein a bearing unit is mounted on a turbine shaft and a compressor blade is not mounted, and the turbine shaft is disposed on the turbine chamber side of the insertion hole. A method for assembling a turbocharger, comprising: incorporating a compressor blade at a free end of a turbine shaft protruding from an opening of a compressor chamber of the insertion hole. 5. A bearing unit for use in a supercharger according to claim 1, wherein the bearing unit is mounted at two positions separated in an axial direction in an intermediate region of the turbine shaft, and the turbine shaft is connected to an inner ring. A rolling bearing having an outer ring outer diameter set to be equal to or smaller than the outer diameter of the bulging portion, and a spring provided between the rolling bearings to elastically urge the outer rings of the rolling bearings in a direction to separate them from each other. And a biasing means. 6. A bearing unit for use in a supercharger according to any one of claims 1 to 3, wherein the bearing unit is mounted at two positions separated in the axial direction in an intermediate region of the turbine shaft, and the turbine shaft is connected to an inner ring. A rolling bearing having an outer ring outer diameter set to be equal to or smaller than the outer diameter of the bulging portion, and a spring provided between the rolling bearings to elastically urge the outer rings of the rolling bearings in a direction to separate them from each other. A bearing unit for a turbocharger, comprising: a biasing means; and a spacer provided between the two rolling bearings to limit an axial displacement amount of the two outer races.