JP3366136B2 - Engine turbocharger - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a turbocharger for an engine equipped with a turbocharger.

[0002]

2. Description of the Related Art Conventionally, as a turbocharger for an engine equipped with a turbocharger, for example, Japanese Patent Publication No. 59-51.
The one shown in Japanese Patent No. 649 is known. In this device, an intake compressor and an exhaust turbine are connected by a turbo rotary shaft, the turbo rotary shaft is rotatably supported by a slide bearing, and a fluid turbine is provided in the middle of the turbo rotary shaft. By injecting oil into the, the drive of the turbo rotary shaft is assisted. A large number of blades are arranged side by side in the circumferential direction in the fluid turbine, and each blade has a U-shape that opens toward an incident fluid (oil), and high-pressure oil must hit these blades. Thereby, the turbo rotary shaft is auxiliary driven.

[0003]

In the above apparatus, it is a major problem to more efficiently transfer the energy of oil to the fluid turbine and eventually to the turbo rotating shaft. In order to improve such efficiency, the following points need to be considered in particular.

A) In a fluid turbine, it is preferable that the oil injected to each blade returns along its U-shaped surface and is discharged almost in the opposite direction to the incident direction. For example, when the oil is injected at a speed v and the turbo rotating shaft and the fluid turbine are rotating at the peripheral speed v / 2, the relative incident speed of the oil to the fluid turbine is v- (v /
2) = v / 2, and assuming that the oil is completely returned by the blade and is discharged in the opposite direction at the same relative speed (v / 2), its absolute discharge speed (speed seen from the stationary system)
Is 0. That is, the kinetic energy of the oil is almost completely utilized for the auxiliary drive, and the efficiency is the highest.

However, in the above apparatus, there is no guarantee that the oil will be reliably guided and returned to the blade surface, and more reliable guidance of such oil is
Desired for efficiency improvement.

B) In the above apparatus, the blades that have not received the oil injection only cause agitation resistance, which rather causes a reduction in auxiliary drive efficiency. Therefore, it is desirable to increase the number of oil injection ports so that the oil is almost always applied to each blade, but conversely, if the number of oil injection ports becomes excessive, a plurality of oil injection ports will be injected to one blade. The oil sprayed from the mouth may hit at the same time, and the sprayed oils may interfere with each other to reduce the driving efficiency.

In view of such circumstances, it is an object of the present invention to provide a turbocharger for an engine capable of improving the auxiliary drive efficiency by injecting a working fluid to a fluid turbine.

[0008]

As a means for solving the above problems, the present invention provides a fluid turbine in the middle of a turbo rotary shaft connecting an intake compressor and an exhaust turbine, and around the fluid turbine. A turbocharger for an engine configured to auxiliary drive the turbo rotary shaft by the energy of the working fluid injected from the fluid injection port to the fluid turbine from the fluid injection port, The position of the fluid injection port and the position of the fluid turbine are substantially matched in the axial direction,
The jetting direction of the working fluid is set to a substantially tangential direction of the fluid turbine, and a plurality of buckets in which the intermediate portion expands in a substantially U shape in the same direction as the incident direction of the working fluid are circumferentially provided in the fluid turbine. The buckets are arranged side by side and are brought close to each other until the buckets adjacent to each other in the circumferential direction overlap each other, and the working fluid is guided between the buckets in a direction substantially opposite to the incident direction. A substantially U-shaped guide groove for discharging is formed (Claim 1).

It is more preferable that the discharge direction of the working fluid from the guide groove be inclined by 15 ° or more and 25 ° or less with respect to the circumferential direction of the fluid turbine (claim 2).

Further, by arranging two of the buckets in the axial direction of the turbo rotating shaft so that the guide groove has a substantially W shape, and the incident position of the working fluid is set at the center position of the guide groove, as will be described later. Above all, a more excellent effect can be obtained (Claim 3).

In this case, by forming an inclined surface along the incident direction of the working fluid in the central portion of the guide groove,
It is more preferable (Claim 4).

Further, a plurality of the fluid ejection ports are arranged side by side in the circumferential direction, and the ratio of the number of the buckets to the number of the fluid ejection ports is set to 1.6 or more and 2.0 or less. ), A bearing is provided between the turbo rotary shaft and the housing of the turbocharger, the fluid turbine is integrally formed with the turbo rotary shaft, and the exhaust turbine can be attached to and detached from the end of the turbo rotary shaft. With such a constitution (claim 6), more excellent effects as described later can be obtained.

Further , the turbo rotary shaft is rotatably supported by an angular ball bearing, and the fluid injection port is formed around the fluid turbine and integrally has a facing wall facing the angular ball bearing. An injection case is provided, and a compression spring is interposed between the opposing wall of the fluid injection case and the angular ball bearing, and the elastic force of the compression spring fixes the axial position of the angular ball bearing. Is preferable (Claim 7).

Further, it is more preferable that the compression spring is arranged closer to the exhaust turbine than the fluid injection case (claim 8).

Further, according to the present invention, a fluid turbine is provided in the middle of a turbo rotary shaft connecting the intake compressor and the exhaust turbine, and a fluid injection port for injecting a working fluid is provided around the fluid turbine. In the turbocharger of the engine configured to auxiliary drive the turbo rotating shaft by the energy of the working fluid injected from the mouth to the fluid turbine, a plurality of buckets are provided side by side in the circumferential direction in the fluid turbine, A plurality of the fluid ejection ports are arranged side by side in the circumferential direction, and the ratio of the number of the buckets to the number of the fluid ejection ports is set to 1.6 or more and 2.0 or less (claim 9). .

[0016]

According to the apparatus of claim 1, the buckets are close to each other until the buckets circumferentially adjacent to each other overlap each other, whereby a U-shaped guide groove is formed between the buckets. Since it is formed, the working fluid injected into the fluid turbine is reliably guided by the guide groove and is discharged in a direction substantially opposite to the direction of its incidence. Therefore, the energy of the working fluid is efficiently transmitted to the fluid turbine and the turbo rotating shaft.

If the flow direction of the working fluid is reversed until the discharge direction of the working fluid from the guide groove substantially matches the circumferential direction of the fluid turbine, the working fluid discharged from each guide groove is Although it may hit the bucket adjacent to, the driving efficiency may be reduced, but the discharge direction of the working fluid is inclined by 15 ° or more and 25 ° or less with respect to the circumferential direction of the fluid turbine as in the device according to claim 2. By doing so, it is possible to auxiliary drive the fluid turbine with high efficiency while eliminating the risk of the discharged working fluid hitting another bucket.

Further, in the apparatus according to the third aspect, two of the buckets are arranged in the axial direction of the turbo rotary shaft so that the guide groove has a substantially W shape, and the incident position of the working fluid is at the center position of the guide groove. Since it is set, the driving efficiency will be higher than in the case where the buckets are in a single row. In addition, since the working fluid that has entered the center of the guide groove is distributed almost evenly to the left and right,
The thrust load generated in the fluid turbine due to the incidence of the working fluid is significantly reduced, and the load on the bearing and the like is reduced.

Further, in the apparatus according to the fourth aspect, since the inclined surface along the incident direction of the working fluid is formed in the central portion of the guide groove, the working fluid is introduced into the guide groove more smoothly. To be done.

[0020] In apparatus according to claim 5, 9, wherein, together with the fluid injection port is a plurality of juxtaposed in the circumferential direction, the ratio of the number of the buckets to the number of the fluid injection port is 1.6 to 2.0 Since it is set as follows, a plurality of fluids are stored in one bucket in the speed state in which the driving efficiency is the best as described above (the ratio of the peripheral speed of the fluid turbine to the injection speed of the working fluid is approximately 1/2). While preventing the working fluid from coming into contact with the injection port, the working fluid can be almost always applied to each bucket, and thereby the fluid turbine and the turbo rotary shaft can be more efficiently assisted and driven.

In the device according to the sixth aspect, since the fluid turbine is formed integrally with the turbo rotary shaft, unlike the case where the both are separate bodies, the mounting for mounting the fluid turbine on the turbo rotary shaft is performed. It is not necessary to provide a member in the middle of the turbo rotary shaft, and centering of this mounting member is also unnecessary. Moreover, since the exhaust turbine is configured to be attachable to and detachable from the end of the turbo rotary shaft, the exhaust turbine is removed from the turbo rotary shaft, and a bearing is externally fitted to the turbo rotary shaft. The turbocharger can be assembled by setting it in the housing of the charger and then mounting the exhaust turbine at the end of the turbo rotary shaft.

Further, in the apparatus according to the seventh aspect , the turbo rotary shaft is supported by an angular ball bearing,
The thrust force of the turbo rotary shaft can be supported by the angular ball bearings, and a compression spring is interposed between the facing wall of the fluid injection case having a fluid injection port and the angular ball bearings, whereby the shaft of the angular ball bearings The directional position can be fixed with a simple structure. Moreover, since the opposed wall is formed integrally with the fluid ejection case, the pressure of the working fluid ejected from the fluid ejection port is not transmitted to the compression spring and the angular contact ball bearing as a thrust force. It is possible to avoid an increase in the rotational resistance of the angular ball bearing due to the thrust force.

Further, in the apparatus according to the eighth aspect , since the compression spring is arranged closer to the exhaust turbine than the fluid injection case, a larger distance is provided between the fluid injection case and the exhaust turbine. As a result, the degree to which the high heat of the exhaust turbine affects the working fluid in the fluid injection case is further reduced.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings.

A common intake pipe 14 is connected to each cylinder of the engine 10 shown in FIG. 3 through an intake manifold 12, and a throttle valve 15, an intercooler 16, a turbocharger (actually described later A turbocharger 24, which also has a function as a supercharger that is auxiliary driven, an air cleaner 18, and the like are provided. Exhaust manifold 1 for each cylinder
A common exhaust pipe 20 is connected to the turbocharger 24 and the exhaust gas purifying catalyst 22 in the middle thereof.
Etc. are provided.

The internal structure of the turbocharger 24 is shown in FIGS. This turbocharger 24, like a normal turbocharger, has an intake compressor 26.
And an exhaust turbine 28. The intake compressor 26 is housed in the compressor housing 30, and the exhaust turbine 28 is housed in the turbine housing 32. The compressor housing 30 is the common intake pipe 14 described above.
The turbine housing 32 is incorporated in the middle of the common exhaust pipe 20, and the two housings 30 and 32 are connected to each other through a substantially cylindrical main body housing 34.

Here, the intake compressor 26 is constructed so as to suck in fresh air in the axial direction and discharge it to the outside in the radial direction by its rotation, whereas the exhaust turbine 28.
Is configured to suck exhaust gas from the outside in the radial direction and discharge it in the axial direction by the rotation thereof.

A turbo rotary shaft 33 connecting the intake compressor 26 and the exhaust turbine 28 is rotatably housed in the center of the main body housing 34. Specifically, male threads 36 and 38 are formed on both ends of the turbo rotary shaft 33, and after the intake compressor 26 and the exhaust turbine 28 are fitted around the respective ends, nuts 37 are screwed onto the male threads 36 and 38, respectively. As a result, the intake compressor 26 and the exhaust turbine 28 are detachably attached.

Inside the main body housing 34, a cylindrical bearing housing 40 is inserted which extends over substantially the entire axial direction thereof. Inside the bearing housing 40,
Angular ball bearings 41 and 42 are inserted, and the turbo rotary shaft 33 is rotatably supported by the angular ball bearings 41 and 42.

At a substantially central portion of the turbo rotary shaft 33,
A hydraulic turbine (fluid turbine) 44 is integrally formed. In this hydraulic turbine 44, a plurality of buckets 43 projecting outward in the radial direction are arranged side by side in the circumferential direction, and two of these buckets 43 are also arranged in the axial direction.
Each of the buckets 43 has such a shape that both sides 43b and 43c of the central portion thereof bulge in a substantially U shape in the circumferential direction (downward in FIG. 1).

The buckets 43 adjacent to each other are close to each other until the intermediate portion of one bucket 43 overlaps with the other bucket 43 in the circumferential direction. More specifically, the surface 43 of the bucket 43 subsequent to the one end 43a of the one bucket 43, which is opposed to the former bucket 43, in the subsequent bucket 43.
b precedes by the dimension L1. By thus bringing the buckets 43 close to each other, a relatively narrow substantially W-shaped guide groove 39 is formed between the buckets 43 adjacent to each other in the circumferential direction.

At the center of the guide groove 39, an inclined surface 43d is formed in a direction along the incident direction of the hydraulic oil to be injected as described later.
Is formed, and the hydraulic oil injected from the center of the guide groove 3
It is guided by 9 and discharged from both ends in a direction substantially opposite to the direction of incidence. The discharge direction at both ends (that is, the longitudinal direction of the guide groove 39) is inclined with respect to the circumferential direction of the fluid turbine (vertical direction in FIG. 1), and the inclination angle θ is 15 ° or more and 25 ° or more. It is set below.

A hydraulic oil injection case 46 is provided around the hydraulic turbine 44. The fluid injection case 46 includes a compressor side member 47 and a turbine side member 48.
And is entirely inserted into the bearing housing 40. A hydraulic oil supply groove 45 is formed around the entire circumference of the central portion of the turbine-side member 48, and a hydraulic oil injection port (fluid injection port) 49 that connects the hydraulic oil supply groove 45 and the hydraulic turbine 44 is circumferentially formed. A plurality of them are formed. The ratio of the number of buckets 43 in a row in the hydraulic turbine 44 to the number of hydraulic oil injection ports 49 is preferably 1.6 or more and 2.0 or less as will be described later in detail. Number) / (number of nozzles) =
It is set as 12 / 7≈1.7.

In the hydraulic oil supply groove 45, a tip end of a hydraulic oil supply nozzle 52 that penetrates the main body housing 34 and the bearing housing 40 in the radial direction faces, and the hydraulic oil supply nozzle 52 has a hydraulic oil supply port. 50 is connected. The hydraulic oil supply nozzle 52 and the hydraulic oil supply port 50 are fixed to the main body housing 34.
The position of the hydraulic oil injection case 46 in which the hydraulic oil supply nozzle 52 is inserted is also fixed.

In the hydraulic oil injection case 46, hydraulic oil discharge grooves 54 are formed at positions on the left and right sides of the hydraulic turbine 44, and the turbine side member 48 and the bearing housing 40 are formed in the hydraulic oil discharge grooves 54. , And a hydraulic oil discharge path 56 formed so as to be continuous with the main body housing 34, and a hydraulic oil discharge pipe 58 is connected to the hydraulic oil discharge path 56. A valve seat 60 is formed in the middle of the hydraulic oil discharge path 56, and a ball (valve body) 62 that is in contact with the valve seat 60 over the entire circumference is housed. The ball 62 and the hydraulic oil discharge pipe 58 are accommodated. A compression spring 64 is provided between Then, in a state where the hydraulic oil is not injected, the ball 62 is pressed against the valve seat 60 by the elastic force of the compression spring 64 to close the valve, while the ball 62 is pressed when the injection pressure of the hydraulic oil exceeds a certain level. 62 is the compression spring 64
The valve is opened apart from the valve seat 60 against the resilience of the valve.

The turbine side member 48 is integrally formed with a facing wall 48a facing the angular contact ball bearing 41 on the exhaust turbine side, and the working oil discharge groove 54 is formed inside the facing wall 48a. . Then, the facing wall 4
The plate 70 and the compression spring 72 are inserted between the 8a and the angular ball bearing 41, and the elastic force of the compression spring 72 fixes the axial position of the angular ball bearing 41 to the position where it contacts the exhaust turbine 28. Has been done. A spacer 66 is provided between the compressor-side member 47 and the angular ball bearing 42, and its axial position is fixed by a snap ring 68. The spacer 66 is interposed between the angular ball bearing 42 and the intake compressor 26. Is spacer 2
7 intervenes.

Returning to FIG. 3, a hydraulic pump 108 is connected to the crankshaft 102 of the engine 10 via a drive transmission mechanism 104 and a pump clutch 106. In this embodiment, a variable displacement pump is used as the hydraulic pump 108, and the hydraulic pump 108 is connected to the hydraulic oil supply port 50 via a pressure regulating valve 110. The hydraulic pump 108 operates by receiving the driving force of the crankshaft 102, and pumps the lubricating oil in the engine 10 as hydraulic oil to the hydraulic oil supply port 50 via the pressure regulating valve 110.

This engine includes a throttle sensor 116 for detecting the throttle opening θ of the throttle valve 15 and an engine speed sensor 11 for detecting the engine speed Ne.
7. An engine intake pipe boost sensor 118 for detecting the pressure in the intake pipe is provided, and these sensors are connected to an ECU (control unit) 120. This EC
The U120 is configured to perform on / off control of the pump clutch 106 according to the engine speed and the acceleration state.

Next, the operation of this device will be described.

First, when the pump clutch 106 is switched on during low-speed acceleration of the engine, the hydraulic pump 108 operates, and the lubricating oil in the engine 10 is regulated to a constant pressure by the pressure regulating valve 110 and then the turbocharger. 24 is supplied to the hydraulic oil supply port 50. The hydraulic oil is injected from the hydraulic oil injection ports 49 through the hydraulic oil supply nozzle 52 and the hydraulic oil supply groove 45 toward the hydraulic turbine 44 in a substantially circumferential direction, whereby the hydraulic turbine 44 and the turbo rotating shaft are integrated. 33 is driven for auxiliary rotation.

More specifically, the hydraulic oil is supplied to the left and right buckets 4
Position between three (that is, central position of guide groove 39)
Is injected into the guide groove 39 along the inclined surface 43d, and while being guided by the guide groove 39, it is in a direction substantially opposite to the direction of incidence (strictly speaking, the inclination angle θ
It is discharged from both sides of the turbine in a tilted direction). When the hydraulic oil is inverted, the energy is transmitted to each bucket 43, and the auxiliary drive is realized.

With the rotation of the turbo rotary shaft 33, the intake compressor 26 sucks intake air in the axial direction and discharges it to the outside in the radial direction, and the exhaust turbine 28 sucks exhaust gas from the outside in the radial direction and discharges it in the axial direction. In this way, when supercharging by auxiliary drive progresses and the engine speed rises above a certain level,
The ECU 120 disengages the clutch 106 to stop the auxiliary drive. From this state, as usual, the exhaust turbine 2
The turbo rotary shaft 33 is rotationally driven by the exhaust energy received by 8, and supercharging is advanced by the compressor 26 connected to the turbo rotary shaft 33.

According to such a device, the following effects can be obtained.

A) In the conventional device, the buckets 43 are separated from each other to the extent that they do not overlap at all, whereas in the above device, the buckets 43 are close to each other until they overlap each other in the circumferential direction. Therefore, the narrow guide groove 39 is formed between the buckets 43. Therefore, the working oil injected into the fluid turbine 44 can be reliably guided and reversed by the guide groove 44, and the energy of the working oil can be more efficiently transmitted to the fluid turbine 44 and the turbo rotary shaft 33.

B) If the flow direction of the hydraulic oil is completely reversed until the discharge direction of the hydraulic oil from the guide groove 39 substantially coincides with the circumferential direction of the fluid turbine 44, each guide groove 3
The hydraulic oil discharged from 9 is the bucket 43 adjacent to the hydraulic oil.
However, in the above device, since the discharge direction of the working oil is inclined by the angle θ (15 ° ≦ θ ≦ 25 °) with respect to the circumferential direction of the fluid turbine, At a minimum, the discharged hydraulic oil can be made to approach the direction opposite to the incident direction while eliminating the risk of hitting the other bucket 43.
As a result, the drive efficiency of the fluid turbine can be improved.

C) Two buckets 43 are arranged in the axial direction of the turbo rotary shaft 33, and a substantially W-shaped guide groove 39 is formed between the buckets 43 adjacent to each other in the circumferential direction.
Since the incident position of the hydraulic oil is set at the center position of 9, the driving efficiency can be further improved as compared with the case where the buckets 43 are in one line. Moreover, since the hydraulic oil that has entered the guide groove 39 can be substantially evenly distributed to the left and right, the thrust load that is generated in the fluid turbine due to the injection of this hydraulic oil is greatly reduced, and the angular ball bearings 41, 42, etc. are burdened. Can be reduced. Further, since the inclined surface 43d along the incident direction of the hydraulic oil is formed in the center of each guide groove 39,
The hydraulic oil can be introduced into the guide groove 39 more smoothly to improve efficiency.

D) The ratio of the number of buckets 43 in a row to the number of hydraulic oil injection ports 49 (hereinafter, simply referred to as "number ratio") is set to 1.6 or more and 2.0 or less. Can be improved.

The reason will be described below. First, the relationship between the injection speed of hydraulic oil and the peripheral speed of the fluid turbine 44 will be considered. As an extreme example, when the two speeds are exactly the same, the relative incident speed of the hydraulic oil to the fluid turbine 44 becomes 0, and the auxiliary drive is substantially not performed. On the other hand, when the oil is injected at the speed v and the turbo rotating shaft and the fluid turbine are rotating at the peripheral speed v / 2, the relative incident speed of the oil to the fluid turbine is v- (v / 2) =
v / 2, and therefore, if the oil is completely returned by the vanes and discharged in the opposite direction at the same relative speed (v / 2), its absolute discharge speed (speed seen from the stationary system) is 0. Becomes That is, the kinetic energy of the oil is almost completely utilized for the auxiliary drive, and the efficiency is the highest.

Under such a speed condition, the most efficient number ratio will be obtained. As an extreme example, when the number ratio is extremely large (for example, when the hydraulic oil injection port 49 is 1
(In the case of one), there are a large number of buckets 43 to which the injected hydraulic oil does not hit at all.
No. 3 is just a stirring resistance and rather reduces the driving efficiency. On the other hand, as shown in FIG. 7A, when the number of injections (the number of hydraulic oil injection ports 49; the number of arrows in FIG. 7A) is equal to the number of buckets 43, that is, the number ratio is 1
In the case of 1, even if the hydraulic turbine 44 is rotating at the peripheral speed v / 2, one bucket 43 is simultaneously hit with the injected hydraulic oil from the plurality of hydraulic oil injection ports 49. Interferes with each other, which in turn reduces efficiency.

On the other hand, when the number ratio is 2, that is, when the number of the hydraulic oil injection ports 49 is half the number of the buckets 43, the interval between the hydraulic oil injection ports 49 is 2 times the interval between the buckets 43. Therefore, when the peripheral speed of the hydraulic turbine 44 is half v / 2 of the hydraulic oil injection speed v (that is,
The relative incident velocity of the hydraulic oil to the hydraulic turbine 44 is v /
2), the hydraulic oil injected from one hydraulic oil injection port 49 hits the bucket 43, and the hydraulic oil injected from the hydraulic oil injection port 49 behind the hydraulic oil injection port 49 is the bucket oil. Therefore, the hydraulic oil from the two hydraulic oil injection ports 49 does not hit one bucket 43 at the same time. Moreover, after each bucket 43 is separated from the hydraulic oil injection port 49 that has received the hydraulic oil until then, the hydraulic oil from the next hydraulic oil injection port 49 immediately hits the bucket 43, so that each bucket 43 is almost It means that the hydraulic oil is constantly in contact. Therefore, theoretically, the driving efficiency becomes maximum when the number ratio is 2.

However, in practice, due to the frictional resistance on the surface of the hydraulic turbine 44, the discharge speed of the hydraulic oil is slightly lower than the incident speed, and the hydraulic oil injection speed v must be set higher accordingly. Therefore, the efficiency is highest when the number ratio is about 1.8. Therefore, it is desirable to set this number ratio in the range of 1.6 or more and 2.0 or less centering on 1.8.

As a control method for effectively utilizing the above-described state in which the peripheral speed of the hydraulic turbine 44 is about 1/2 of the hydraulic oil injection speed v (that is, the most efficient state), for example, Something like this.

The hydraulic oil injection speed is fixed, and the hydraulic oil injection speed is set so that the above state appears at the initial stage of acceleration.

Hydraulic turbine 44 after acceleration is started
Of the peripheral speed of the hydraulic oil is predicted, and the hydraulic oil injection speed v is increased with time so that the hydraulic oil injection speed v is always twice the predicted peripheral speed of the hydraulic turbine 44.
This hydraulic oil injection speed v can be controlled by changing the discharge capacity of the hydraulic pump 108 which is a variable capacity pump.

The peripheral speed of the hydraulic turbine 44 is detected in real time during acceleration, and the hydraulic oil injection speed v is controlled so as to maintain the hydraulic oil injection speed v at twice the detected peripheral speed.

E) The hydraulic turbine 44 is attached to the turbo rotary shaft 33.
Since they are integrally formed with each other, it is not necessary to provide a mounting member for mounting the hydraulic turbine 44 to the turbo rotary shaft 33 in the middle of the turbo rotary shaft 33, unlike the case where both are separate bodies. No need for centering work. Moreover, since the exhaust turbine 28 is detachably attached to the end portion of the turbo rotary shaft 33, the exhaust turbine 28 is separated from the turbo rotary shaft 33 even if the hydraulic turbine 44 is integrally formed as described above. In the removed state, the angular contact ball bearing 42, the spacer 66, the snap ring 68, the hydraulic oil injection case 46, the compression spring 40, the plate 70, and the angular contact ball bearing 41 around the turbo rotary shaft 33.
The turbocharger 24 can be assembled by mounting the exhaust turbine 28 on the end portion of the turbo rotary shaft 33 after arranging the components in the bearing housing 40.

F) The thrust force acting on the turbo rotary shaft 33 can be supported by the angular ball bearings 41, 42, and the compression spring 72 is provided between the opposing wall 48a of the hydraulic oil injection case 46 and the angular ball bearing 41. By interposing it, the axial position of the angular ball bearing 41 can be fixed with a simple structure. Moreover, since the opposed wall 48a is formed integrally with the hydraulic oil injection case 46, the pressure of the hydraulic oil discharged to the hydraulic oil discharge groove 54 in the hydraulic oil injection case 46 is the same as that of the compression spring 72 and the angular contact. It is not transmitted to the ball bearing 41. Therefore, the thrust force does not act on the angular ball bearing 41 due to the pressure, and the rotational resistance of the angular ball bearing 41 does not increase due to the thrust force.

G) Since the compression spring 72 is arranged on the side closer to the exhaust turbine 28 than the fluid injection case 46, a larger distance is provided between the hydraulic oil injection case 46 and the exhaust turbine 28 accordingly. Can be secured. For this reason,
The adverse effect of high heat of the exhaust turbine 28 on the hydraulic oil in the hydraulic oil injection case 46 can be further reduced.

In FIG. 1, if the width of the guide groove 39 is too narrow, it becomes impossible to receive all the hydraulic oil injected from the hydraulic oil injection port 49 into the guide groove 39.
In practice, the guide groove 39 is arranged so that the cross-sectional area of the hydraulic fluid passages on the left and right sides of the guide groove 39 is 1/2 or more (preferably 1/2 or more and 1 or less) of the cross-sectional area of the hydraulic oil supply nozzle 49.
It is better to set the width of.

In the above embodiment, two buckets 43 are arranged in the axial direction, but only one bucket 43 is arranged in the axial direction, and one end of the bucket 43 is filled with hydraulic oil. The turbo rotating shaft 3
Auxiliary drive of 3 is possible.

[0061]

As described above, according to the present invention, the following effects can be obtained.

According to the apparatus of claim 1, the buckets are brought close to each other until the buckets circumferentially adjacent to each other overlap each other, whereby a U-shaped guide groove is formed between the buckets. Therefore, the working fluid injected into this fluid turbine can be reliably inverted by the guide groove in the direction substantially opposite to the direction of incidence, and discharged, which allows the energy of the working fluid to be efficiently transferred to the fluid turbine and turbo rotation. There is an effect that can be used for auxiliary drive of the shaft.

Here, in the apparatus according to the second aspect, the discharge direction of the working fluid is 15 with respect to the circumferential direction of the fluid turbine.
Since it is inclined by at least 25 ° but not more than 25 °, the discharge direction of the working fluid can be brought close to the circumferential direction of the fluid turbine within a range in which the discharged working fluid can be prevented from hitting another bucket, thereby improving the driving efficiency. There is an effect that it can be further improved.

Further, in the apparatus according to the third aspect, two of the buckets are arranged in the axial direction of the turbo rotary shaft so that the guide groove has a substantially W shape, and the incident position of the working fluid is at the center position of the guide groove. Since the setting is made, the driving efficiency can be further improved as compared with the case where the buckets are in a single row, and the working fluid incident on the center of the guide groove can be evenly distributed right and left. The thrust load generated in the fluid turbine due to the incidence of is greatly reduced, and the load on the bearing and the like can be reduced.

Further, in the apparatus according to the fourth aspect, since the inclined surface along the incident direction of the working fluid is formed in the central portion of the guide groove, the working fluid can be introduced into the guide groove more smoothly. Therefore, there is an effect that the driving efficiency can be further improved.

In the apparatus according to claims 5 and 9 , a plurality of fluid ejection ports are arranged side by side in the circumferential direction, and the ratio of the number of buckets to the number of fluid ejection ports is 1.6 or more.2.
Since it is set to 0 or less, a plurality of fluid injection ports are provided in one bucket in the speed state in which the driving efficiency is the best (the ratio of the peripheral speed of the fluid turbine to the injection speed of the working fluid is approximately 1/2). While preventing the working fluid from hitting,
Since it is possible to apply the hydraulic oil to each bucket almost constantly, this has the effect of assisting the fluid turbine and the turbo rotary shaft more efficiently.

In the apparatus according to the sixth aspect, since the fluid turbine is formed integrally with the turbo rotary shaft, unlike the case where the two are separate bodies, the mounting for mounting the fluid turbine on the turbo rotary shaft is performed. It is not necessary to provide a member in the middle of the turbo rotary shaft, and centering of this mounting member is also unnecessary. Moreover, since the exhaust turbine is configured to be attachable to and detachable from the end of the turbo rotary shaft, the exhaust turbine is removed from the turbo rotary shaft, and a bearing is externally fitted to the turbo rotary shaft. The turbocharger can be assembled by setting it in the housing of the charger and then mounting the exhaust turbine at the end of the turbo rotary shaft.

Further, in the apparatus according to the seventh aspect , by supporting the turbo rotary shaft with an angular ball bearing,
The thrust force of the turbo rotary shaft can be supported by the angular ball bearings, and a compression spring is interposed between the facing wall of the fluid injection case having a fluid injection port and the angular ball bearings, whereby the shaft of the angular ball bearings The directional position can be fixed with a simple structure. Moreover, since the opposing wall is formed integrally with the fluid ejection case, the pressure of the working fluid ejected from the fluid ejection port is not transmitted to the compression spring and the angular contact ball bearing, so that this pressure causes As a result, it is possible to avoid an increase in the rotational resistance of the angular ball bearing.

Further, in the device according to the eighth aspect , since the compression spring is arranged on the side closer to the exhaust turbine than the fluid injection case, the space between the fluid injection case and the exhaust turbine is correspondingly increased. A large distance can be secured, and the degree to which the high heat of the exhaust turbine affects the working fluid in the fluid injection case can be further reduced.

[Brief description of drawings]

FIG. 1 is a front view showing a bucket shape of a fluid turbine provided in a turbocharger according to an embodiment of the present invention.

FIG. 2 is a sectional side view of the fluid turbine.

FIG. 3 is an overall configuration diagram of an engine including the turbocharger.

FIG. 4 is a sectional front view of the turbocharger.

FIG. 5 is a sectional front view showing a main part of the turbocharger.

FIG. 6 is a sectional side view showing a main part of the turbocharger.

FIG. 7A is an explanatory view showing an example in which the ratio of the number of hydraulic oil supply nozzles to the number of buckets of the fluid turbine is set to 1, and FIG. 7B shows the number of hydraulic oil supply nozzles to the number of buckets of the fluid turbine. It is explanatory drawing which shows the example which set the ratio to 2.

[Explanation of symbols]

10 engine 24 turbocharger 26 Intake compressor 28 Exhaust turbine 33 Turbo rotating shaft 34 body housing 39 Guide groove 40 bearing housing 41,42 Angular contact ball bearing 43 buckets 43d slope 44 Hydraulic turbine (fluid turbine) 46 Hydraulic oil injection case 48a Opposite wall 49 Hydraulic oil injection port 72 Compression spring

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) F02B 37/10 F02B 39/00 F03B 1/02 F02B 39/08

Claims (9)

(57) [Claims] 1. A fluid turbine is provided in the middle of a turbo rotary shaft connecting an intake compressor and an exhaust turbine, and a fluid injection port for injecting a working fluid is provided around the fluid turbine, and the fluid injection port is provided from the fluid injection port. In a turbocharger for an engine configured to auxiliary drive the turbo rotary shaft by the energy of a working fluid injected into a fluid turbine, the position of the fluid injection port and the position of the fluid turbine are substantially aligned in the axial direction. The injection direction of the working fluid is set to a substantially tangential direction of the fluid turbine, and the fluid turbine is surrounded by a plurality of buckets in which an intermediate portion bulges in a substantially U-shape in the same direction as the incident direction of the working fluid. Buckets that are arranged side by side and that are adjacent to each other in the circumferential direction until they overlap each other. A turbocharger for an engine, characterized in that a substantially U-shaped guide groove for guiding the working fluid and discharging the working fluid in a direction substantially opposite to the incident direction is formed between the ports. 2. The turbocharger for an engine according to claim 1, wherein the discharge direction of the working fluid from the guide groove is inclined by 15 ° or more and 25 ° or less with respect to the circumferential direction of the fluid turbine. And turbocharger for the engine. 3. The turbocharger for an engine according to claim 1, wherein two of the buckets are arranged in the axial direction of the turbo rotary shaft to form the guide groove in a substantially W shape, and the guide groove is located at a central position of the guide groove. A turbocharger for an engine, wherein an incident position of the working fluid is set. 4. The turbocharger for an engine according to claim 3, wherein an inclined surface along the incident direction of the working fluid is formed in the central portion of the guide groove. . 5. The turbocharger for an engine according to claim 1, wherein a plurality of the fluid injection ports are arranged side by side in the circumferential direction, and the number of the buckets with respect to the number of the fluid injection ports. A turbocharger for an engine, characterized in that the ratio is set to 1.6 or more and 2.0 or less. 6. The turbocharger for an engine according to claim 1, wherein a bearing is provided between the turbo rotary shaft and a housing of the turbocharger, and the fluid turbine is mounted on the turbo rotary shaft. A turbocharger for an engine, characterized in that the exhaust turbine is detachably attached to an end of the turbo rotary shaft. 7. The turbocharger for an engine according to claim 6, wherein the turbo rotary shaft is rotatably supported by an angular contact ball bearing, and the fluid injection port is formed around the fluid turbine, and A fluid injection case integrally having an opposed wall facing the angular ball bearing is disposed, and a compression spring is interposed between the opposed wall of the fluid injection case and the angular ball bearing to repel the compression spring. A turbocharger for an engine, wherein the axial position of the angular contact ball bearing is fixed by force. 8. The turbocharger for an engine according to claim 7, wherein the compression spring is arranged closer to the exhaust turbine than the fluid injection case. 9. A fluid turbine is provided in the middle of a turbo rotary shaft connecting an intake compressor and an exhaust turbine, and a fluid injection port for injecting a working fluid is provided around the fluid turbine, and the fluid injection port is provided from the fluid injection port. In a turbocharger for an engine configured to auxiliary drive the turbo rotating shaft by the energy of a working fluid injected into a fluid turbine, a plurality of buckets are arranged side by side in the fluid turbine in the circumferential direction, and A turbocharger for an engine, wherein a plurality of fluid injection ports are arranged side by side in the circumferential direction, and a ratio of the number of buckets to the number of fluid injection ports is set to 1.6 or more and 2.0 or less. .