JPH0247203Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a turbocharger (exhaust supercharger) with a variable displacement turbine.

[Conventional technology]

Conventionally, an exhaust supercharger is often used as a means for increasing the output per cylinder volume of an internal combustion engine.

This exhaust supercharger uses a turbine to receive high-temperature, high-pressure exhaust gas supplied from the exhaust manifold of an internal combustion engine, and supercharges each cylinder via the intake manifold by driving a blower that is directly connected to the turbine.

Generally, an exhaust supercharger attached to an internal combustion engine is designed to correspond to the set operating range of the internal combustion engine and to exhibit a predetermined supercharging effect, but in this case,
When the internal combustion engine approaches the lower limit of its set operating range,
The supercharging effect of an exhaust supercharger often decreases.

In order to increase the supercharging effect in such low-speed operating ranges and increase the low-speed torque of the internal combustion engine, an exhaust supercharger with a variable displacement turbine (hereinafter simply referred to as an exhaust supercharger or turbocharger) is used. Ru.

For example, in the exhaust supercharger 1 shown in FIG. 5 having such a function, a plurality of nozzle vanes 4 are arranged in an annular row in an annular inlet 3 around the turbine wheel 2.

When the amount of exhaust gas flowing into the annular inlet 3 is large, each nozzle vane 4 is spaced apart from other adjacent nozzle vanes and supported so as not to create a large resistance to the exhaust gas.

On the other hand, when the amount of exhaust gas flowing into the annular inlet 3 is small, each nozzle vane 4 is rotated to narrow the distance between them.

Thereby, even if the amount of exhaust gas flowing in is small, its velocity energy can be effectively applied to the turbine wheel 2, so that the internal combustion engine can increase low-speed torque.

Such an exhaust supercharger 1 includes, as members for operating the nozzle vanes 4, a nozzle vane shaft 6 pivoted to a back plate 9 attached to a bearing housing 5, a lever 7 fixed to the nozzle vane shaft 6, and a lever 7 fixed to the nozzle vane shaft 6. It has a rotating ring 8 rotatably supported by a bearing housing 5 connected to the rotating end side of the lever 7.

When assembling the exhaust supercharger 1 equipped with these nozzle vane operating members, first the rotary ring 8 is fitted onto the bearing housing 5, and then the back plate 9 to which a plurality of nozzle vanes 4 are attached is attached.
is fixed to the bearing housing 5. moreover,
The lever 7 on each nozzle vane side is connected to the rotating ring 8 side.

[Problem that the invention attempts to solve]

By the way, in order to assemble such an exhaust supercharger 1, it is first necessary to fit the rotation ring 8 onto the bearing housing 5, and for this purpose, the bearing housing 5 and the back plate 9 are made separate parts. Later, it will be necessary to connect the two.

Further, there is also a problem in that the work of connecting the lever 7 and the rotation ring 8 requires time and effort.

Furthermore, in order to eliminate the above problems,
When the rotating ring 8 is divided, the rotating ring 8
Since it is not desirable to supply lubricating oil to the sliding contact between the inner circumference and the outer circumference of the bearing housing 5, the sliding contact of the exhaust supercharger 1 should not be exposed to harsh conditions such as high temperature and dry atmosphere. However, there is no accurate means to sufficiently reduce the frictional resistance, and the problem is that it wears out.

This invention aims to solve these problems, and it is easy to assemble, and
It is an object of the present invention to provide a variable exhaust inlet turbocharger that can prevent wear on the sliding part of a rotating mechanism equipped to adjust the opening of a turbine exhaust introduction part.

[Means for solving problems]

Therefore, the variable exhaust inlet turbocharger of the present invention includes a bearing housing that supports a center shaft, a turbine housing attached to an axial end of the bearing housing, in a turbocharger connected to an engine.
A turbine impeller disposed within the turbine housing and attached to the end of the center shaft; a plurality of nozzle vanes arranged in a row along the circumferential direction of the annular inlet and capable of changing the opening area of the annular inlet by rotation; and one end fixed to the nozzle vane. A support shaft that is pivotally supported by the bearing housing and extends outside the bearing housing, and a rotation mechanism that is connected to the other end of the support shaft to rotate the rotation mechanism are provided. An annular groove formed on the outer periphery of the bearing housing, a plurality of ring bearings installed in the annular groove, and a pair of ring supports whose inner arcuate ends slide into contact with the bearing surface on the outer periphery of the ring bearing. A ring fixed on the outer periphery of the pair of ring supports, a lever formed to connect the ring and the support shaft and convert the rotation of the ring into rotation of the support shaft, and a lever that rotates the ring. In addition, in order to prevent wear between the ring bearing and the ring support, the ring support is made of austenitic stainless steel, and the ring bearing is made of austenitic stainless steel. It is characterized by chrome plating on the surface.

[Effect]

With the above configuration, the exhaust supercharger can be easily assembled, and during operation, the turbine side opening of the exhaust supercharger is smoothly adjusted so that the capacity corresponds to the engine operating condition. This prevents wear on the sliding contact area due to sliding between the ring support and the ring bearing, resulting in stable operation.

〔Example〕

Hereinafter, an embodiment of the present invention will be explained with reference to the drawings. Figures 1 to 4 show a variable exhaust inlet turbocharger as an embodiment of the present invention.
Figure 1 is a schematic diagram of the main parts of the ring bearing, Figure 2
The figure is a longitudinal sectional view thereof, FIG. 3 is a sectional view taken along the - arrow in FIG. 2, and FIG. 4 is a sectional view taken along the - arrow in FIG.

As shown in FIGS. 2 to 4, the exhaust supercharger 10 is
An outer frame is formed by a central bearing housing 11 and a blower housing 12 and a turbine housing 13 that are respectively attached to both ends of the bearing housing in the axial direction.
The bearing housing 11 pivotally supports a center shaft 15 through a floating metal 14 approximately at the center thereof.

The center shaft 15 has a blower fan wheel 16 and a turbine wheel 17 attached to its left and right ends.

An oil passage 19 for supplying oil to the floating metal 14 is formed in a bearing support portion 18 in the bearing housing 11 that supports the floating metal 14. Note that the reference numeral 20 indicates an oil discharge port.

The bearing housing 11 and the turbine housing 13 are fastened and fixed by an annular connecting belt 21. A turbine wheel 17 is housed between the two, and a turbine housing 1 facing the outer circumference of the turbine wheel 17 is provided.
3 has an annular inlet 22 formed therein.

High-temperature, high-pressure exhaust gas is supplied to this annular inlet 22 from the exhaust manifold side of the engine (not shown).
The turbine wheel 1 receives the velocity energy of this exhaust gas.
7 is set to rotate.

On the right end side of the bearing housing 11, a plurality of nozzle vanes 24 are pivotally attached to a wall portion 23 at the position of the annular inlet 22.

As shown in FIG. 3, a plurality of nozzle vanes 2
4 are arranged along the circumferential direction of the annular inlet 22, and are arranged so that their axial directions coincide with the axial direction of the turbine.

Further, each nozzle vane 24 has a wall portion 23
(See FIG. 2) is fixed to one end of a support shaft 25 that extends through and is pivotally supported. Each nozzle vane 2
4, by rotating the support shaft 25, the distance t between the adjacent nozzle vanes 24 is changed;
Thereby, the opening amount of the annular inlet 22 can be changed.

Each support shaft 25 is pivotally attached to the wall via a sleeve 26, and a lever 27 is attached to the other end.

Note that the sleeve 26 may be securely fixed to the bearing housing 11 by a presser plate 32, or
In order to reduce the accumulation tolerance of the axial clearance between the nozzle vane 24 and the turbine housing 13, a slight gap is provided between the sleeve 26 and the holding plate 32 so that the holding plate 32 and the bearing housing 11 are in close contact with each other. may be configured.

The levers 27 are attached to each support shaft 25 and arranged radially around the center shaft 15, and each lever 27 is connected to the ring 31 at its rotation end.

This ring 31 has a pair of ring supports 2
8 is attached.

Each ring support 28 has an arcuate end 281 formed inside thereof that slides into an annular groove 30 formed in the outer circumferential wall 111 of the bearing housing 11, and an outer end 282 of the ring support 28 that is connected to the ring 31 by a bolt 38.
is fixed.

A rotating portion 29 is formed by integrally assembling the pair of ring supports 28 and the ring 31, and this rotating portion 29 is fitted onto the annular groove 30 and rotates around the center shaft 15. It has become possible to move.

Furthermore, as shown in FIG. 2, the ring 31 is attached with a pin 33 that protrudes in a direction parallel to the center shaft direction A.
3 is engaged with a U-shaped end 271 (see FIG. 4) formed at the pivot end of each lever 27 via a slider 51.

A connecting piece 34 is provided protruding from the outer peripheral surface of the ring 31, and an actuator 35 is connected to this connecting piece 34.

By applying an output signal from a drive control mechanism (not shown) to this actuator 35,
The ring 31 of the rotating portion 29 is rotated by a predetermined amount.

In this way, ring 31, ring support 2
8, the pin 33, the lever 27, the slider 51, the support shaft 25, the connecting piece 34, and the actuator 35 constitute a rotation mechanism for the nozzle vane 24.

Incidentally, reference numeral 36 denotes a bearing surface 36 that is disposed within the annular groove 30, is press-fitted into the bottom of the annular groove 30, and is in sliding contact with the arcuate end 281 of the ring support.
1 is shown, and four ring bearings 36 are installed in the annular groove 30 to constitute a bearing for the ring support 28 in the rotating portion 29.

Annular groove 30 and arcuate end 28 of ring support 28
Molybdenum disulfide S as a fixed lubricant is sealed between the inner circumference of the ring bearing 36 and the inner circumference of the arc end 281 to reduce the frictional resistance when the ring support 28 rotates at the sliding portion between the outer circumference of the ring bearing 36 and the inner circumference of the arc end 281. It is starting to decrease.

Further, at the arc end 281, one guide 50 is provided between each pair of ring bearings 36, 36.
is attached by press-fitting its base 50a.

As a result, the guide 50 is driven as the ring support 28 rotates, and the flat plate portion of the guide 50 moves the inner periphery of the arcuate end 281 and the ring bearing 36.
Molybdenum disulfide S can be guided and supplied between the outer periphery and the outer periphery.

The ring bearing 36 and the inner periphery of the arcuate end 281 of the ring support 28 are arranged so that the ring support 28 is made of austenitic stainless steel and the inner periphery of the ring support 28 is made of austenitic stainless steel, as shown in FIG. Chrome plating is applied to the outer peripheral bearing surface of the bearing 36 to form a chrome plating layer 36.
a is formed.

The ring bearing 36 is made of S43C as the base material.
The ring bearing 36 is formed from a low-cost base material.

Further, by forming the ring support 28 from austenitic stainless steel such as SUS304, rust can be prevented.

In other words, no wear-resistant member has been provided that is effective under the harsh conditions of high temperature, dry air, such as the sliding part in this example, and data for aerospace technology in high temperature, dry vacuum has not been provided. It's just that it's being done.

The above combination of materials has been confirmed to have wear resistance under the above conditions as a result of various experiments, and allows the rotating portion 29 to operate stably over a long period of time.

Since the exhaust inlet variable turbocharger as an embodiment of the present invention is constructed as described above, the assembly work of the exhaust supercharger 10 shown in FIG. 2 is performed as follows.

First, the bearing housing 11 is placed on a pedestal (not shown).

At this time, the bearing housing 11 has its wall portion 23 facing upward, and all of the nozzle vanes 24 are pivotally attached to this wall portion 23.

Subsequently, all the levers 27 on the nozzle vane 24 side are arranged radially with respect to the center shaft center line l.

Next, the ring support 28 is inserted into the annular groove 30, and the inner circumference of the arcuate end 281 is inserted into the ring bearing 36.
bring it into contact with.

and the outer end 282 of the ring support 28.
are assembled to the ring 31 with bolts 38 to make them integral. At this time, the slider 51 pivotally supported by the ring 31 is brought into engagement with the U-shaped end 271 of the lever 27.

As a result, the ring support 28 and the ring 31 are fitted onto the annular groove 30, and the rotating portion 29 and the plurality of nozzle vanes 24 are connected.

Next, the center shaft 15 to which the turbine impeller 17 is attached is fitted into the bearing support portion 18, and further the turbine housing 13 is stacked on the bearing housing 11, and both are fixed with the connecting belt 21.

After this, the bearing housing 11 side is reversed, and the blower fan wheel 1 is attached to the upward center shaft 15.
Insert 6 and tighten the nut.

Next, the blower housing 12 is superimposed on the bearing housing 11, and both are fixed with the connecting belt 37, and the assembly of the exhaust supercharger 10 is almost completed. Note that the center shaft 15 may be attached before the nozzle vane 24 is assembled.

Such an exhaust supercharger 10 is attached to an engine (not shown) and is driven by receiving exhaust gas, but at this time, the exhaust gas flows into the turbine wheel 17 through the interval t on the side of each nozzle vane on the annular inlet 22 side. do.

Here, if the inflow amount of exhaust gas exceeds the set amount, the blower fan wheel 16 side performs proper supercharging operation.

On the other hand, when the inflow amount of exhaust gas falls below the set amount, the rotating portion 29 is operated by a drive control mechanism (not shown), and the rotating portion 29 is rotated around the center shaft 15 by the actuator 35, and interlocks with this. Each nozzle vane 24 is rotated.

As a result, the interval t between each nozzle vane is narrowed, and the opening amount of the annular inlet 22 is reduced, so even if the amount of exhaust gas flowing into the annular inlet 22 is reduced, the velocity energy of the exhaust gas is kept at a predetermined level. Can be retained.

In other words, even if the displacement is reduced to some extent during low-speed operation, by narrowing the opening amount of the annular inlet 22, the turbine wheel 17 receives enough velocity energy from the exhaust gas to obtain a supercharging effect.
This allows the low-speed torque of the internal combustion engine to be increased.

By the way, when the rotating part 29 rotates, the arcuate end 281 of the ring support 28 slides smoothly due to the molybdenum disulfide S supplied between the inner circumference of the arcuate end 281 and the outer circumference of the ring bearing 36.
The rotating portion 29 can be rotated smoothly.

That is, when the rotating part 29 rotates, the guide 50 is driven by the rotation of the ring support 28, and the guide 50 moves the molybdenum disulfide S to the arcuate end 2.
Molybdenum disulfide S is guided and supplied to the sliding part gap between the inner periphery of the ring bearing 81 and the outer periphery of the ring bearing 36, and a sufficient amount of molybdenum disulfide S is always supplied to the sliding part gap.

Note that molybdenum disulfide S is applied to the surface of the ring bearing 36 in advance.

The ring support 28 is made of austenitic stainless steel, and the outer peripheral bearing surface of the ring bearing 36 is chrome plated to form a chrome plating layer 36a.
1, the sliding portion 29 can be slid against the inner periphery without causing wear of the member, and the rotating portion 29 can operate stably over a long period of time.

Furthermore, the ring bearing 36 can be made of a low-cost material such as S43C.

Furthermore, since the ring support 28 is made of austenitic stainless steel, rust can be prevented.

As described above, according to the exhaust supercharger 10 as an embodiment of the present invention shown in FIGS. 1 to 4, the assembly of each member for operating the nozzle vane 24 is simpler than before. That is, the wall portion 23 to which the nozzle vane 24 is pivotally attached is formed as the bearing housing 11, and there is no need to assemble the portion corresponding to the wall portion 23 and the bearing housing 11 as in the conventional art.

In order to obtain such an effect, the rotating portion 29 is connected to the ring 31 and the pair of ring supports 2.
8, but these assembly operations are also completed simply by bolting.

Furthermore, the connection between the ring 31 and the lever 27 is also
Simply slider 51 and lever 27 on ring 31 side.
This is a work to engage the U-shaped end 271 by fitting, and these assembly works can be easily performed.

[Effect of idea]

As detailed above, according to the variable exhaust inlet turbocharger of the present invention, the turbocharger connected to the engine includes a bearing housing that supports the center shaft, and a turbine housing that is attached to the axial end of the bearing housing. a turbine wheel disposed within the turbine housing and attached to the end of the center shaft; and a turbine wheel facing the outer periphery of the turbine wheel within the turbine housing to allow the exhaust gas of the engine to flow into the turbine wheel. a plurality of nozzle vanes arranged in a row along the circumferential direction of the annular inlet and capable of changing the opening area of the annular inlet by rotation; and one end fixed to the nozzle vane. At the same time, a support shaft that is pivotally supported by the bearing housing and extends outside the bearing housing, and a rotation mechanism that is connected to the other end of the support shaft and rotates the rotation mechanism are provided. is an annular groove formed on the outer periphery of the bearing housing, a plurality of ring bearings installed in the annular groove, and a pair of ring supports whose inner arcuate ends slide into contact with the bearing surface on the outer periphery of the ring bearing. , a ring fixed on the outer periphery of the same pair of ring supports, a lever formed to connect the ring and the support shaft and convert rotation of the ring into rotation of the support shaft, and the ring. In order to prevent wear between the ring bearing and the ring support, the ring support is made of austenitic stainless steel, and the ring bearing is made of austenitic stainless steel. The simple structure of the bearing surface is chrome-plated, making it easy to assemble, and even under harsh conditions such as high temperature and dry atmosphere, the turbine side exhaust inlet opening This has the advantage of preventing wear on the sliding parts for adjustment and maintaining good and stable operating conditions for a long period of time.

Further, there is an advantage that the cost of the sliding part can be reduced and rust can be prevented.

[Brief explanation of the drawing]

Figures 1 to 4 show a variable exhaust inlet turbocharger as an embodiment of the present invention, in which Figure 1 is a schematic diagram of the main part of its ring support, Figure 2 is its longitudinal sectional view, and Figure 3 is its longitudinal sectional view. A sectional view taken along the − arrow in FIG.
FIG. 4 is a sectional view taken along the - arrow in FIG.
The figure is a cutaway side view of essential parts of a conventional variable displacement exhaust supercharger. 10... Exhaust supercharger (turbocharger), 1
1...Bearing housing, 12...Blower housing, 13...Turbine housing, 14...
... Floating metal, 15 ... Center shaft, 16 ... Blower fan wheel, 17 ... Turbine wheel, 18 ... Bearing support part, 19 ... Oil passage, 20 ...
...Oil discharge port, 21...Connection belt, 22...
Annular inlet, 23... Wall, 24... Nozzle vane, 25... Support shaft, 26... Sleeve, 27...
Lever, 28... Ring support, 29... Rotating part, 30... Annular groove, 31... Ring, 32...
Holding plate, 33... Pin, 34... Connection piece, 35...
...Actuator, 36...Ring bearing,
36a...Chrome plating layer, 37...Connection belt, 38...Bolt, 50...Guide, 50a...
... Base, 51 ... Slider, 111 ... Outer peripheral wall,
271... U-shaped end, 281... Arc end, 282...
...outer end, 361... bearing surface, l... center shaft center line, S... molybdenum disulfide as solid lubricant.

Claims (1)

[Scope of utility model registration request] A turbocharger connected to an engine includes a bearing housing that supports a center shaft, a turbine housing attached to an axial end of the bearing housing, and a turbine housing disposed within the turbine housing and attached to the center shaft end. a turbine wheel; and an annular inlet formed in the turbine housing to face the outer periphery of the turbine wheel in order to allow exhaust gas from the engine to flow into the turbine wheel; a plurality of nozzle vanes arranged in a row along the axis and capable of changing the opening area of the annular inlet by rotation thereof; and a support shaft having one end fixed to the nozzle vane, pivotally supported by the bearing housing, and extending outside the bearing housing. and a rotation mechanism connected to the other end of the support shaft to rotate the support shaft, and the rotation mechanism has an annular groove formed on the outer periphery of the bearing housing and a rotation mechanism within the annular groove. A plurality of ring bearings are attached to the ring bearing, a pair of ring supports whose inner arcuate ends slide into contact with the bearing surface on the outer periphery of the ring bearing, a ring fixed on the outer periphery of the same pair of ring supports, and the same ring. It consists of a lever formed to connect with the support shaft and convert the rotation of the ring into rotation of the support shaft, and a drive control mechanism that rotates the ring, and the ring bearing. A variable exhaust inlet type, characterized in that the ring support is made of austenitic stainless steel, and the bearing surface on the outer periphery of the ring bearing is chrome-plated in order to prevent wear with the ring support. Turbo charger.