JPH0583333U - Lubricator for turbocharger - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent a large amount of oil from leaking by immediately stopping or controlling the oil supply to the turbocharger in the event of an abnormality involving oil leakage in the turbocharger. [Composition] Normally, an oil supply hole 7d and an oil outlet hole 6a formed in the peripheral wall of the cylinder 7 of the valve means 2 provided on the upstream side of the turbocharger 1 are divided into two chambers in the cylinder 7 by the spool valve 3. The spring 7 of the oil 7a, 7b exists on the side of the chamber 7a in which the spring 8 is housed, and the oil in the oil main gallery 60 is supplied to the chamber 7a through the throttle portion 4a and directly to the chamber 7a. Is supplied to the center housing 30, and at the time of an abnormality that oil leakage occurs on the downstream side of the chamber 7a, the spring 8 is generated according to the hydraulic pressure difference between the chamber 7a and the chamber 7b.
The spool valve 3 displaced against the pressure can close the oil supply hole 7d or the oil supply hole 7d and the outlet hole 6a.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to improvement of a lubrication device for a turbocharger.

[0002]

[Prior Art]

 In the turbocharger of an internal combustion engine, the compressor wheel is damaged due to some cause (for example, foreign matter that has fallen downstream of the cleaner element when cleaning the air cleaner reaches the turbocharger compressor after a long period of operation). However, it is possible that the driver may not continue to notice the fact of the damage and continue the operation, or even if it is noticed, it may be necessary to move to a maintenance shop and the operation may continue.

In such a case, the compressor wheel is rotated at a high speed in a rotationally unbalanced state, and as a result, the bearing that supports the wheel shaft is unevenly worn, and the rotation axis of the wheel shaft deviates from the normal position. .. Due to this deviation, the sealability of the oil seal interposed in the portion where the wheel shaft penetrates the center housing deteriorates, and the oil supplied for cooling / lubrication from there is supplied to the turbine housing or compressor housing. There is a risk of leaking to.

Then, for example, when oil leaks into the compressor housing, the oil flows into the combustion chamber and is burned there. If abnormal combustion occurs at this time, a sudden pressure increase in the cylinder at that time occurs. The worst case may cause deformation of the conrot, and if oil leaks into the turbine housing, it may burn in the hot exhaust pipe and emit a large amount of white smoke to the rear of the vehicle. There is.

In order to avoid such a failure due to oil leakage when the turbocharger is abnormal during the operation of the engine, a predetermined operation is conventionally performed based on, for example, the engine load, the engine speed, and the turbocharger speed. The standard intake pressure in the state is calculated, the actual intake pressure is detected by the intake pressure sensor, and when the detected value deviates from the standard intake pressure by more than the specified value, it is judged as an abnormality of the turbocharger and the turbocharger is judged. There is a method of stopping the supply of oil (see JP-A-64-80720).

[0006]

[Problems to be solved by the device]

 However, in such an abnormality determination method, the value of the standard intake pressure value varies depending on the operating state, and also varies depending on the engine, turbocharger, etc., so there is an enormous amount of data regarding abnormality determination. At the same time, there is a drawback in that it is very troublesome to properly set this huge amount of data.

[0007]

[Means for Solving the Problems]

 The present invention was devised in view of the above, and in a lubrication device for a turbocharger of an internal combustion engine, a spool valve that is housed in a cylinder so as to be displaceable in the axial direction and divides the cylinder into at least two chambers. And a spring that is housed in one of the two chambers and that biases the spool valve in a direction in which the volume of the other chamber becomes smaller and the spool valve is displaced by being biased by the spring. Valve means having an oil supply hole and an oil outlet hole formed in the cylinder peripheral wall so as to exist on the one chamber side, one end of which is connected to an oil supply source of the internal combustion engine through a throttle portion. The other end is a first oil pipe connected to the oil supply hole of the one chamber, one end is connected to a center housing that accommodates the bearing of the turbocharger, and the other end is the one of the chamber. A second oil pipe connected to the oil outlet hole, and a third oil pipe having one end connected to the oil supply port of the other chamber and the other end connected to the oil supply source. When an oil leak occurs on the downstream side of the chamber, the spool valve operates against the biasing force of the spring by the hydraulic pressure from the third oil pipe, and the oil supply hole on the one chamber side or the oil supply hole on the one chamber side. And the gist is that the outlet hole is configured to be closed or controlled.

[0008]

According to this, when the engine is started, the spool valve is urged by the spring until just before that, and the oil is supplied to the first chamber while opening the supply hole. When oil is supplied from the first chamber to the center housing of the turbocharger through the second oil pipe, but an oil leak occurs at the downstream side of the valve means interposed between the center housing and the oil supply source. Since the oil pressure in the one chamber where the oil is supplied through the throttle is immediately reduced, the urging force of the spring is generated by the oil pressure in the other chamber where the oil is supplied without passing through the throttle. Against the above, the spool valve is displaced so that the volume of the one chamber becomes small, and at this time, the spool valve causes the oil supply hole of the one chamber or the supply hole and the outlet hole of the one chamber. Will be closed.

[0009]

【Example】

 Hereinafter, a first embodiment of the present invention will be described in detail with reference to FIG. In the turbocharger 1 of this embodiment, when exhaust energy of an engine (not shown) passes through the turbine housing 10, the turbine wheel 11 obtains rotational kinetic energy, and the rotational force of the turbine wheel 11 causes the wheel shaft to rotate. The air transmitted to the compressor wheel 21 via 35 and sucked in the compressor housing 20 is compressed by the rotation of the compressor wheel 21 and sent to the combustion chamber of the engine.

In the center housing 30, a wheel shaft 35 is rotatably supported by a bearing 50 serving as a bearing. During operation of the engine, the wheel shaft 35 is provided in the center housing 30 via an oil supply hole 30c and an oil passage 30d. The oil is constantly supplied to lubricate and cool the bearing 50.

Here, the wheel shaft 35 penetrates through holes 30 a and 30 b formed between the center housing 30 and the turbine housing 10 and between the center housing 30 and the compressor housing 20, respectively. The right end projects into the turbine housing 10 and the left end projects into the compressor housing 20, and oil leaks into the turbine housing 10 or the compressor housing 20 through the gap between the through holes 30a and 30b and the wheel shaft 35. In order to prevent this, oil seals 40 are respectively interposed between the through holes 30a and 30b and the wheel shaft 35.

By the way, the oil is supplied to the center housing 30 by an oil passage provided so as to communicate the inside of the center housing 30 and the oil main gallery 60 via the throttle portion 4a, that is, the throttle portion 4a in the figure. , The first oil pipe 4, the valve means 2, and the second oil pipe 6 connected to the oil outlet hole 6a of the cylinder 7, the oil passage 30d, the bearing 50, the housing shaft support 31, and the wheel shaft 35. Through the gap 50a of the above.

The center housing 30 is further connected to an oil return pipe 9 on the downstream side. The oil supplied to the center housing 30 is at atmospheric pressure or almost atmospheric pressure, and the oil is returned through the oil return pipe 9. It is designed to be returned to a pan (not shown).

Here, since the gap 50a such as the oil passage 30d in the oil supply passage and the cooling / lubricating passage of the bearing 50 exerts a function of a throttle, the gap 50a between the throttle portion 4a and the oil passage 30d and the gap 50a. It is possible to keep the oil pressure of the specified pressure.

The valve means 2 is capable of controlling opening / closing of the passage by displacing the spool valve 3 housed in the cylinder 7 in the axial direction. The inside of the cylinder 7 is divided into at least two chambers, in the present embodiment, two chambers, that is, a first chamber 7a and a second chamber 7b, and in FIG. 1, one end of a spring 8 is provided in the first chamber 7a. The other end is stored in the left side wall 7e in the cylinder 7 so as to abut (on the left side in the drawing) the spring retainer portion 3b of the recess 3a on the left side of the spool valve 3.

[0016] Normally (during normal operation and immediately before starting), in the case of the present embodiment, the spool valve 3 is at the maximum displacement position of P1 due to the spring force of the spring 8, and at this time, the first The chamber 7a is connected to the first oil pipe 4 through an oil supply hole 7d formed in the outer wall of the cylinder 7, and further through the throttle portion 4a, an oil supply source, which is an oil main gallery 60 in this embodiment. Is in communication with.

The second chamber 7b is directly connected to the oil main gallery 60 by the third oil pipe 5 not through the throttle portion but directly through the oil supply port 5a.

That is, normally, a force F1 acting on the spool valve 3 from the left side in the figure (a force corresponding to the spring force of the spring 8 and the pressure of the oil supplied through the first oil pipe 4 through the throttle portion 4a) is applied. 2) and the force F2 acting on the spool valve 3 from the right side in the figure (the force corresponding to the pressure of the oil supplied through the third oil pipe 5) are balanced.

Further, when oil leaks from the equilibrium state on the downstream side of the valve means 2, the supply of oil is restricted by the throttle portion 4a provided in the middle of the first oil pipe 4 on the upstream side. As a result, the steady-state oil pressure during normal operation immediately decreases, and at this time the oil pressure in the second chamber 7b does not change, so the spool valve 3 is changed according to the decrease in the oil pressure in the first chamber 7a. The spring 8 is displaced leftward in the figure to a new equilibrium position against the biasing force of the spring 8 to control or stop the supply of oil according to the amount of oil leakage.

In the above embodiment, the opening side end portion 3c of the recess 3a of the spool valve 3 is provided on the step portion 7c formed so that the inner diameter of the cylinder 7 is rapidly reduced near the left side of the oil supply hole 7d. The maximum displacement of the spool valve 3 to the left is restricted at the position P2 here, and as shown by the dotted line in FIG. 1, at this time, the oil supply hole 7d is completely removed by the outer peripheral wall 3d of the spool valve 3. It is designed to be blocked. Further, even if the stepped portion 7c is provided at an appropriate position on the left side in the figure and both the oil supply hole 7d and the outlet hole 6a of the first chamber are closed, the same effect as the above embodiment can be obtained. be able to.

As described above, according to this embodiment, when the turbocharger 1 is in an abnormal state with oil leakage, the turbocharger 1 is immediately transferred to the turbocharger 1 by the valve means 2 interposed between the turbocharger 1 and the oil main gallery 60. Oil supply is controlled or stopped, and there is a concern when a large amount of oil leaks.For example, due to abnormal combustion of oil in the combustion chamber, deformation of the conrot or exhaust pipe This has the effect of preventing various problems such as the release of a large amount of white smoke behind the vehicle due to the burning of oil.

Next, a second embodiment will be described with reference to FIG. 2. The same parts as those of the first embodiment will be described with the same reference numerals as much as possible. In the valve means 2, in addition to the first embodiment, a spring retainer portion 302 that receives the spring force of the spring 8 is provided by a connecting member 303 provided in the spool valve body 301 of the spool valve 3 as shown in FIG. It is possible that it extends on the left side of the figure. Here, the spring retainer 302 part divides the first chamber 7a into two spaces A and B, and in the space shown in FIG. 2, the space A accommodates the spring 8 in the same manner as in the first embodiment. It is open to the atmosphere inside the internal combustion engine through the outlet hole 6e. The space B of the first chamber 7a is connected to the oil supply hole 7d to which the first oil pipe 4 that is normally open is connected, and the second oil supply pipe 6 is connected to the oil outlet. The hole 6a is connected.

Next, the operation of the second embodiment will be described. In this case, similarly to the first embodiment, when the oil seal 40 in the center housing 30 is damaged and the oil leaks, the oil in the second oil pipe 6 also suddenly flows out and the space B in the first chamber 7a is discharged. The oil pressure decreases and the oil pressure in the second chamber 7b causes the spool valve 3 to move to the position shown by the dotted line in the figure against the urging force of the spring 8 to move the oil supply hole 7d and the outlet hole 6a to the spool valve outer peripheral wall 301d. Close. Meanwhile, the oil in the space A of the first chamber 7a is discharged through the outlet hole.

In the second embodiment, by providing the spring retainer portion 302 separately from the spool valve body 301, the size of the spring having a desired spring force can be set independently, and the degree of freedom in design is increased. Since it is slid at two positions apart from each other in the axial direction, that is, the outer peripheral wall 301d of the spool valve body and the outer peripheral wall 302a of the spring retainer portion 302, it is possible to reduce the deviation in the displacement direction of the spool valve. effective.

[0025]

[Effect of the device]

 Therefore, according to the present invention, when an oil leak occurs on the downstream side of the valve means interposed between the center housing of the turbocharger and the oil supply source, the opening of the valve means is immediately and accurately closed. The supply of oil to the center housing is controlled or stopped, and as a result, the oil that leaks to the intake system abnormally explodes in the combustion chamber, causing a sudden rise in cylinder pressure and deforming the connecting rod and leaking to the exhaust system. This has the effect of eliminating the problems associated with the large amount of oil leaking, such as the oil being burned in the hot exhaust pipe and a large amount of white smoke being emitted to the rear of the vehicle.

[Brief description of drawings]

FIG. 1 is a system diagram of a first embodiment of a lubrication device for a turbocharger, showing a main part of the present invention.

FIG. 2 is a sectional view of a valve means as a second embodiment having a different form from the first embodiment.

[Explanation of symbols]

 1 Turbocharger 10 Turbine housing 20 Compressor housing 30 Center housing 35 Wheel shaft 40 Oil seal 50 Bearing 2 Valve means 3 Spool valve 7 Cylinder 7a 1st chamber 7b 2nd chamber 8 Spring 4 1st oil pipe 4a Throttling part 5 3rd Oil pipe 6 Second oil pipe 60 Oil main gallery

Claims (1)

[Scope of utility model registration request] 1. A turbocharger for an internal combustion engine, comprising:
The spool valve is housed in the cylinder so as to be displaceable in the axial direction and divides the cylinder into at least two chambers, and is housed in either one of the two chambers, and the volume of the other chamber becomes smaller. A spring for urging the spool valve and an oil supply hole and an oil outlet hole formed in the cylinder peripheral wall so as to be present on the one chamber side when the spool valve is displaced by being urged by the spring. A valve means, a first oil pipe whose one end is connected to an oil supply source of the internal combustion engine through a throttle portion and the other end is connected to an oil supply hole of the one chamber, and one end of which is a bearing of the turbocharger. A second oil pipe connected to the center housing for accommodation and having the other end connected to the oil outlet hole of the one chamber, one end connected to the oil supply port of the other chamber and the other end thereof A third oil pipe connected to the oil supply source, and at least when an oil leak occurs on the downstream side of the one chamber, the spool valve is biased by the spring by the hydraulic pressure from the third oil pipe. Lubrication device for a turbocharger, characterized in that the oil supply hole on one side of the chamber or the oil supply hole and the outlet hole of the one chamber is closed or controlled.