CN110857676B

CN110857676B - Compressor unit

Info

Publication number: CN110857676B
Application number: CN201910760192.9A
Authority: CN
Inventors: 上原英世; 村上光规; 芦川秀法
Original assignee: Honda Motor Co Ltd
Current assignee: Honda Motor Co Ltd
Priority date: 2018-08-23
Filing date: 2019-08-16
Publication date: 2021-11-19
Anticipated expiration: 2039-08-16
Also published as: JP6655138B1; JP2020029822A; CN110857676A

Abstract

The present invention provides a compressor unit, comprising: the compressor (101) compresses intake air of an engine using an impeller (11), an impeller chamber (110) which houses the impeller (11) so that the impeller can rotate, an intake flow path (111) which extends along an axis (CL) of the impeller (11) and introduces the intake air into the impeller chamber (110), a ventilation flow path (112) which is provided so as to intersect the axis (CL) of the impeller (11) and introduces blow-by gas of the engine into the intake flow path (111), and a rectifying plate (120) which is provided along the axis (CL) of the impeller (11) between an inlet (112a) of the ventilation flow path (112) which faces the intake flow path (111) and the impeller chamber (110). The rectifying plate (120) is disposed offset in a direction perpendicular to the axis (CL) of the impeller (11) with respect to the inlet (112a) of the ventilation flow path (112).

Description

Compressor unit

Technical Field

The present invention relates to a compressor unit mounted on a vehicle.

Background

There is known a compressor including an impeller (rotor) which compresses intake air and supplies the compressed intake air to an internal combustion engine, and a rectifying plate which is fixed to an intake air flow passage on an upstream side with respect to the impeller, at least a part of which protrudes toward a rotation axis side from an outer peripheral edge of an inlet of the impeller and extends in a direction of the rotation axis, as viewed in the rotation axis direction of the impeller. Such a device is described in patent document 1, for example.

However, the blow-by gas leaked into the crankcase of the internal combustion engine may flow back to the upstream side of the impeller in the flow path of the intake air. Therefore, for example, in the compressor described in patent document 1, when blowby gas is recirculated to the upstream side of the rectifying plate in the intake air flow path, there is a possibility that liquid such as oil and unburned fuel contained in the blowby gas adheres to the rectifying plate.

Documents of the prior art

Patent document 1: japanese patent laid-open publication No. 2015-105644 (JP 2015-105644A).

Disclosure of Invention

The compressor unit according to an aspect of the present invention includes: a compressor that compresses intake air of an internal combustion engine using an impeller; an impeller chamber that houses an impeller so that the impeller can rotate; an intake flow path extending along an axis of the impeller and introducing intake air into the impeller chamber; a ventilation flow path that introduces blow-by gas of the internal combustion engine into the intake flow path; and a rectifying plate provided along the axis of the impeller between an inlet of the ventilation flow path, which is opposite to the intake flow path, and the impeller chamber. The rectifying plate is disposed offset from the inlet of the ventilation flow path in a direction orthogonal to the axis of the impeller.

Drawings

The objects, features and advantages of the present invention are further clarified by the following description of the embodiments in relation to the accompanying drawings.

Fig. 1 is a perspective view showing a schematic configuration of a supercharging system of an engine according to an embodiment of the present invention.

Fig. 2 is a plan view showing a schematic configuration of the supercharging system of fig. 1.

Fig. 3 is a cross-sectional view showing the intake duct taken along line III-III of fig. 2.

Fig. 4 is a longitudinal sectional view showing the air intake duct taken along line IV-IV of fig. 2.

Fig. 5 is a cross-sectional view of an intake duct provided with a flow regulating plate according to modification 1 of the embodiment of the present invention.

Fig. 6 is a longitudinal sectional view of an intake duct provided with a flow regulating plate according to modification 2 of the embodiment of the present invention.

Fig. 7 is a vertical cross-sectional view of an intake duct provided with a flow regulating plate according to modification 3 of the embodiment of the present invention.

Fig. 8 is a graph showing a relationship between the opening degree of the outlet throttle valve and the standard deviation of the output of the air flow meter.

Detailed Description

An embodiment of the present invention will be described below with reference to fig. 1 to 8. The compressor unit according to an embodiment of the present invention is mounted on a vehicle.

Fig. 1 is a perspective view showing a schematic configuration of a supercharging system 10 of an engine 1 including a compressor unit 200 according to an embodiment of the present invention, and fig. 2 is a plan view showing the schematic configuration of the supercharging system 10 of fig. 1. In fig. 1, the supercharging system 10 is shown by a solid line, and other structures are shown by a two-dot chain line. The supercharging system 10 pressurizes intake air supplied to the engine 1 by driving the compressor 101 to rotate using exhaust energy of the engine 1, which is an internal combustion engine.

As shown in fig. 1 and 2, the supercharging system 10 has: a supercharger 100 disposed on a side portion of the engine 1, an air cleaner case 21, an intake duct 24 connecting the supercharger 100 and the air cleaner case 21, and a ventilation duct 26 disposed along an upper portion of the engine 1. In a state where the engine 1 and the supercharging system 10 are mounted on the vehicle, as shown in fig. 1, the breather pipe 26 is laid on an upper portion of the supercharger 100, an inlet 112a of the breather passage 112 is positioned above an intake passage 111 (described later), and blow-by gas is introduced from above the intake passage 111 (see fig. 3 and 4).

As shown in fig. 2, the supercharger 100 includes a turbine 102 disposed in an exhaust flow path and a compressor 101 disposed in an intake flow path. The compressor unit 200 of the present embodiment is configured by the compressor 101, a flow path (an intake flow path 111, etc.) leading to the compressor 101, and the like.

In the turbine 102, a plurality of worm blades 22 are provided radially on a rotating shaft, and are rotated by energy of exhaust gas discharged from an exhaust part of the engine 1. That is, the worm wheel blade 22 converts the energy of the exhaust gas into mechanical energy. The compressor 101 includes an impeller 11 mechanically coupled to a rotating shaft of the worm wheel blade 22 and rotating integrally with the worm wheel blade 22. The impeller 11 is a centrifugal impeller that converts an axial flow into a radial flow and pressurizes the radial flow. The compressor 101 compresses intake air using the impeller 11 and supplies the compressed intake air to an intake portion (engine cylinder not shown) of the engine 1. Although not shown, the impeller 11 includes a wheel coupled to the rotation shaft of the worm wheel blade 22 and a plurality of blades provided on a conical hub surface of the wheel. The blades are provided at equal intervals in the circumferential direction on the hub surface of the wheel.

The air cleaner box 21 purifies air (outside air) entering from the outside. The upstream end of the intake duct 24 is connected to the air cleaner case 21, and the downstream end is connected to the supercharger 100. The air cleaner case 21 is provided with a pipe joint 21a connected to an intake duct 24, and an air flow meter 25 for detecting the flow rate of intake air is attached to the pipe joint 21 a.

The intake duct 24 extends substantially horizontally in a state of being mounted on the vehicle. The downstream-side end portion of the intake duct 24 is connected to the housing 13 that constitutes the outline of the supercharger 100. The housing 13 has a main housing 130 that houses the impeller 11 and the worm wheel blade 22, and an intake duct 140 provided between the main housing 130 and the intake duct 24. The intake duct 140 is formed in a substantially L-shape in a horizontal plane.

Fig. 3 is a cross-sectional view of the intake duct 140 taken along line III-III of fig. 2, and fig. 4 is a longitudinal sectional view of the intake duct 140 taken along line IV-IV of fig. 2. Fig. 3 and 4 are side views of intake duct 140 mounted on the vehicle. That is, the vertical direction in fig. 3 and 4 is the same as the vertical direction when the supercharging system 10 is mounted on the vehicle. As shown in fig. 3, the left-right direction of intake duct 140 is defined as shown in the drawing.

As shown in fig. 3, one end of the breather pipe 26 is connected to an introduction portion 145 provided at an upper portion of the intake duct 140, and the other end is connected to a crankcase (not shown) of the engine 1. The ventilation duct 26 is laid so as to be slightly inclined downward from the horizontal plane toward one end (the intake duct 140).

As shown in fig. 4, the impeller 11 is disposed such that the rotation center axis (axial line) CL thereof is substantially horizontal. The main casing 130 is formed with an impeller chamber 110 that houses the impeller 11 so that the impeller 11 can rotate. As shown in fig. 2, the upstream end of the intake duct 140 is connected to the intake duct 24, and the downstream end is connected to the main casing 130.

As shown in fig. 3 and 4, the intake duct 140 is a tubular intake air flow passage forming portion in which the intake air flow passage 111 is formed as an intake air flow passage. In the present embodiment, the 1 st member 140a on the upstream side and the 2 nd member 140b on the downstream side are joined to form the intake duct 140. By forming the air intake duct 140 from a plurality of parts, the die-drawing operation during the die-forming can be easily performed.

The intake passage 111 extends along the axis CL of the impeller 11 and introduces intake air into the impeller chamber 110. As shown in fig. 3, the intake duct 140 is generally rectangular as a whole, and includes a pair of side plates 141 facing each other in the left-right direction, a top plate 142 connecting upper end portions of the pair of side plates 141 to each other, and a bottom plate 143 disposed facing the top plate 142 and connecting lower end portions of the pair of side plates 141 to each other. That is, the intake duct 140 is formed in a frame shape having a substantially rectangular cross section.

The top plate 142 is provided with an introduction portion 145 to which the ventilation duct 26 is connected. The introduction portion 145 is a cylindrical ventilation flow path forming portion in which the ventilation flow path 112, which is a flow path of blow-by gas, is formed. The ventilation passage 112 is provided so that its extension, for example, intersects the axis CL of the impeller 11, and introduces blow-by gas from the engine 1 into the intake passage 111. More specifically, the ventilation passage 112 is provided such that the center line thereof is orthogonal to the axis line CL of the impeller 11, and blow-by gas is introduced into the horizontally extending intake passage 111 from the vertically upper side to the vertically lower side. The top plate 142 is provided with a through hole as an inlet 112a through which blow-by gas is introduced from the breather flow path 112 to the intake flow path 111. As shown in fig. 3, an inlet 112a of the ventilation passage 112 facing the intake passage 111 is configured to be located within a range of the lateral width of the small cross-sectional passage 151 configuring the inlet of the impeller chamber 110 when viewed from the intake upstream side along the axis CL.

As shown in fig. 3 and 4, the intake passage 111 includes a small-cross-sectional passage (1 st passage) 151 provided on the main casing 130 side and constituting an inlet of the impeller chamber 110, and a large-cross-sectional passage (2 nd passage) 152 provided on the intake duct 24 side. The small-cross-sectional flow channel 151 has a circular flow channel cross section. The large-cross-sectional flow channel 152 has a rectangular flow channel cross-section, which is larger than the flow channel cross-section of the small-cross-sectional flow channel 151.

As shown in fig. 3, the small-cross-section flow passage 151 is formed such that the entire small-cross-section flow passage 151 is disposed inside the large-cross-section flow passage 152 when viewed from the intake upstream side along the axis CL of the impeller 11. As shown in fig. 4, a tapered portion 153 that is inclined so that the flow path cross-sectional area decreases from the large-cross-sectional flow path 152 to the small-cross-sectional flow path 151 is provided between the large-cross-sectional flow path 152 and the small-cross-sectional flow path 151, whereby the flow path cross-sectional shape gradually changes.

A flat flow rectification plate 120 having a substantially rectangular or trapezoidal shape is provided on the top plate 142. The rectifying plate 120 is provided to extend downward from the top plate 142. The rectifying plate 120 is integrally formed with, for example, a top plate 142 of the 1 st member 140a constituting the inner peripheral surface of the intake duct 14. The flow regulating plate 120 may be fixed to the top plate 142 by welding or the like, with the flow regulating plate 120 being a separate member from the intake duct 140.

The rectifying plate 120 is provided along the axis CL of the impeller 11 between the inlet 112a of the ventilation flow path 112, which is opposite to the intake flow path 111, and the impeller chamber 110. More specifically, as shown in fig. 3 and 4, the flow straightening plate 120 is disposed such that the longitudinal direction is parallel to the axis CL of the impeller 11, the short-side direction is parallel to the vertical direction, and the thickness direction is parallel to the left-right direction. That is, the longitudinal direction and the thickness direction of the current plate 120 are parallel to the horizontal direction. As shown in fig. 4, the end of the rectifying plate 120 on the inlet 112a side of the ventilation passage 112 is formed along the vertical direction, and the end on the impeller chamber 110 side is formed along the tapered portion 153.

As shown in fig. 3, the rectifying plate 120 is disposed offset from the inlet 112a of the ventilation flow path 112 in a direction perpendicular to the axis CL of the impeller 11 and perpendicular to the vertical direction, that is, in the width direction (left-right direction) of the intake duct 140. That is, the flow rectification plate 120 is disposed outside the inlet 112a of the ventilation flow passage 112 so as not to block the flow of blow-by gas from the inlet 112a of the ventilation flow passage 112 to the impeller chamber 110 along the axis CL of the impeller 11 when viewed along the axis CL. In the present embodiment, the flow regulating plate 120 is disposed offset to the left of the intake duct 140 with respect to the inlet 112a of the ventilation passage 112, as viewed from the intake upstream side along the axis CL.

The main flow of the intake air purified by the air cleaner box 21 flows into the intake duct 140 through the intake duct 24 in the direction indicated by the arrow 90 in fig. 4. Then, the blow-by gas flows into the intake duct 140 through the breather pipe 26 in the direction indicated by the arrow 91 in fig. 3 and 4, that is, in the direction substantially perpendicular to the main flow of intake air (see the arrow 90).

In the compressor unit 200, in the low flow rate region, the angle of attack of the intake air increases at the inlet of the impeller 11, and a reverse flow of the intake air is generated around the inlet of the impeller 11. The reverse flow from the impeller 11 side to the intake passage 111 is a swirling flow swirling in the same direction as the rotation direction of the impeller 11, as indicated by an arrow 93 in fig. 3 and 4.

As shown in fig. 3, the rectifying plate 120 is disposed so as to intersect the swirling flow in order to block the swirling flow and rectify the intake air. In the present embodiment, the swirling flow swirls counterclockwise when viewed from the intake upstream side. Therefore, the rectifying plate 120 of the present embodiment is disposed on the upstream side of the swirling flow in the upper portion of the intake passage 111 so as to block the swirling flow that flows from the impeller chamber 110 back to the intake passage 111 from flowing toward the inlet 112a of the ventilation passage 112.

The upstream side of the swirling flow in the upper portion of the intake passage 111 refers to a region on the left side of the axis line CL when viewed from the upstream side of the swirling flow passing through the upper portion of the intake passage 111, that is, from the intake upstream side along the axis line CL, if the rectifying plate 120 is not provided. The downstream side of the swirling flow in the upper portion of the intake passage 111 is a region on the right side of the axis line CL when viewed from the downstream side of the swirling flow passing through the upper portion of the intake passage 111, that is, from the intake upstream side along the axis line CL, if the rectifying plate 120 is not provided.

The tip end (lower end) of the rectifying plate 120 is positioned above the small cross-sectional flow passage 151 constituting the inlet of the impeller chamber 110. In other words, the flow regulating plate 120 is disposed radially outward of the circumferential surface of the small cross-sectional passage 151 so as not to overlap the small cross-sectional passage 151 when viewed from the intake upstream side along the axis CL of the impeller 11. This can reduce the resistance (intake flow resistance) to the main flow (see arrow 90 in fig. 4) of the intake air flowing through the small cross-sectional flow passage 151.

As shown in fig. 4, the length of the flow regulating plate 120 in the longitudinal direction is set to be longer than the pitch of the swirling flow in the counter flow (the distance that the flow advances along the axis CL during one rotation). This can effectively reduce the swirl component of the swirling flow.

The present embodiment can provide the following effects.

(1) The compressor unit 200 of the present embodiment includes: a compressor 101 that compresses intake air of the engine 1 as an internal combustion engine using an impeller 11; an impeller chamber 110 that houses the impeller 11 so that the impeller can rotate; an intake flow path 111 that extends along the axis CL of the impeller 11 and introduces intake air into the impeller chamber 110; a ventilation passage 112 provided so as to intersect with the axis CL of the impeller 11 and configured to introduce blow-by gas of the internal combustion engine into the intake passage 111; and a flow regulating plate 120 provided between the inlet 112a of the ventilation passage 112 facing the intake passage 111 and the impeller chamber 110 along the axis CL of the impeller 11 (see fig. 1 to 4). Therefore, surging can be suppressed by reducing the swirl component of the reverse flow by the flow regulating plate 120.

The rectifying plate 120 is disposed offset in a direction (leftward) perpendicular to the axis CL of the impeller 11 with respect to the inlet 112a of the ventilation flow path 112 (see fig. 3). Therefore, the rectifying plate 120 is not present at a position facing the inlet 112a of the ventilation flow path 112. This can suppress blow-by gas introduced from the inlet 112a of the ventilation passage 112 into the intake passage 111 and flowing toward the impeller 11 from being directly blown onto the flow rectification plate 120. Therefore, according to the present embodiment, it is possible to effectively suppress the adhesion of liquid such as oil and moisture contained in the blow-by gas to the flow straightening plate 120.

Further, in the case where the flow regulating plate 120 is disposed only on the upstream side of the inlet 112a of the ventilation passage 112 (not shown), the liquid contained in the blow-by gas can be prevented from adhering to the flow regulating plate 120, but the swirl component of the reverse flow from the impeller chamber 110 cannot be reduced in the region close to the impeller chamber 110 (the region from the impeller chamber 110 to the ventilation passage 112). In contrast, in the present embodiment, the rectifying plate 120 is disposed at a position shifted to the left in fig. 3 with respect to the inlet 112a of the ventilation passage 112 on the downstream side of the inlet 112a of the ventilation passage 112. Therefore, as described above, according to the present embodiment, surge can be suppressed by the flow regulating plate 120, and liquid contained in blow-by gas can be suppressed from adhering to the flow regulating plate 120.

(2) The rectifying plate 120 is disposed so as to block a swirling flow, which flows from the impeller chamber 110 to the intake passage 111, from flowing to the inlet 112a of the ventilation passage 112. That is, the rectifying plate 120 is disposed on the swirling flow inlet side of the upper portion of the intake passage 111 (see fig. 3). This can effectively suppress the blowby gas from being entrained in the swirling flow that flows back from the impeller chamber 110 to the intake flow path 111, and can suppress contamination of the intake flow path 111.

(3) The rectifying plate 120 is provided to extend downward from the top plate 142 forming the intake passage 111, and a tip end portion (lower end portion) of the rectifying plate 120 is positioned above an inlet of the impeller chamber 110 (see fig. 3). This can reduce the resistance (intake flow resistance) to the main flow of intake air (see arrow 90 in fig. 4). In use in cold regions or the like, even if the liquid accumulated in the bottom of the intake passage 111 freezes, the effect of the rectifying plate 120 can be maintained. On the other hand, when the rectifying plate is attached so as to extend upward from the bottom surface (bottom plate 143) of the intake passage 111, there is a possibility that the liquid accumulated in the bottom of the intake passage 111 is frozen in a state of adhering to the rectifying plate, and the function of the rectifying plate is broken.

The above embodiment can be modified into various forms. The following describes modifications. In the above embodiment, the example in which the flow regulating plate 120 is disposed on the left side of the inlet 112a of the ventilation flow path 112 as viewed from the intake upstream side along the axis CL of the impeller 11 as shown in fig. 3 is described. However, when the rotation direction of the impeller 11, that is, the swirling direction of the reverse flow from the impeller 11 side to the intake flow path 111 is the reverse direction, the rectifying plate 120 is disposed on the right side of the inlet 112a of the ventilation flow path 112 in the drawing.

In the above embodiment, an example in which one rectifying plate 120 is disposed has been described, but the present invention is not limited to this. As shown in fig. 5, a pair of (2) rectifying plates 120 may also be arranged. The pair of flow regulating plates 120 are disposed on both right and left sides of the inlet 112a of the ventilation flow path 112, that is, on the swirling flow inlet side and the swirling flow outlet side of the upper portion of the intake flow path 111, when viewed from the intake upstream side along the axis CL of the impeller 11.

In other words, the pair of flow regulating plates 120 are arranged such that the inlet 112a of the ventilation flow path 112 is positioned between the pair of flow regulating plates 120 when viewed from the intake upstream side along the axis CL of the impeller 11. The rectifying plate 120 is provided in a direction perpendicular to the axis CL of the impeller 11 with respect to the inlet 112a of the ventilation flow path 112, and at a position on one side (left) and a position offset to the other side (right) in a direction (left-right direction) perpendicular to the vertical direction, whereby the blowby gas can be more effectively suppressed from being involved in the swirling flow, and the contamination of the intake flow path 111 can be suppressed. Further, the swirl component of the backflow can be more effectively reduced, and surging can be suppressed.

The rectifying plate 120 may be divided along the axis CL of the impeller 11. For example, as shown in fig. 6, the rectifying plate 120 may be divided at the boundary between the 1 st member 140a mainly constituting the large cross-sectional flow passage 152 and the 2 nd member 140b mainly constituting the small cross-sectional flow passage 151 and the tapered portion 153. That is, the 1 st flow rectification plate 120A having a rectangular shape in side view may be provided in the 1 st member 140A, and the 2 nd flow rectification plate 120B having a trapezoidal shape in side view may be provided in the 2 nd member 140B. This makes it easier to attach the current plate 120.

Further, as shown in fig. 7, a 1 st flow rectification plate 120A having a rectangular shape in side view may be provided in the 1 st member 140A, and a 2 nd flow rectification plate 120B may be omitted. Further, as shown in fig. 6, by providing the 2 nd flow straightening plate 120B, the swirling flow of the reverse flow generated by the impeller 11 can be eliminated in the vicinity of the generation position.

Referring to fig. 8, the flow straightening effect of the flow straightening plate 120 will be described based on the experimental results. Fig. 8 is a graph showing the relationship between the opening degree of the outlet throttle valve and the standard deviation of the output of the air flow meter 25. In fig. 8, the horizontal axis represents the opening degree of the outlet throttle valve provided between the compressor 101 and the intake portion (engine cylinder) of the engine 1, and the vertical axis represents the standard deviation of the output of the air flow meter 25.

The larger the swirl component of the reverse flow, the larger the deviation of the output of the air flow meter 25. Therefore, the rectification effect by the rectification plate 120 can be determined by measuring the standard deviation of the output of the airflow meter 25 by an experiment.

The experimental result of the reference example in the case where the rectifying plate 120 is not provided is taken as (result 1), and the experimental result of the comparative example in which the distance from the compressor 101 to the airflow meter 25 is set to about 1.2 times as compared with the reference example is taken as (result 2). The experimental result of the example in the case where one sheet of the 1 st flow rectification plate 120A shown in fig. 7 is provided as shown in fig. 3 is taken as (result 3), and the experimental result of the example in the case where 2 sheets of the 1 st flow rectification plate 120A shown in fig. 7 is provided as shown in fig. 5 is taken as (result 4). The experimental results in the case where 2 rectifying plates 120 shown in fig. 4 are provided as shown in fig. 5 are taken as (result 5), and the experimental results in the example in the case where the 1 st rectifying plate 120A and the 2 nd rectifying plate 120B shown in fig. 6 are provided as shown in fig. 5 are taken as (result 6). The reference example is different from the embodiments only in the presence or absence of the rectifying plate 120, and the other configurations are the same.

As shown in fig. 8, from the experimental results (result 1) of the reference example and the experimental results (result 2) of the comparative example, it can be determined that: the longer the distance between the compressor 101 and the airflow meter 25, the smaller the standard deviation of the output of the airflow meter 25, and the smaller the influence of the counter-flow swirling flow on the measurement result of the airflow meter 25. In contrast, in the experimental results (results 3 to 6) of all the examples provided with the rectifying plate 120, it was confirmed that: in a small flow rate region (region where the opening degree is greater than 0 DEG and less than 2 alpha DEG) where the opening degree of the outlet throttle valve is small, the standard deviation of the air flow meter 25 is small as compared with the experimental result (result 1) of the reference example and the experimental result (result 2) of the comparative example, and the swirl component of the reverse flow can be reduced by the rectifying plate 120.

Thus, the swirl component of the reverse flow can be more effectively reduced by providing the flow regulating plate 120 than by extending the distance between the compressor 101 and the airflow meter 25. That is, by providing the flow regulating plate 120 as described above, the supercharging system 10 can be downsized, and the swirl component of the reverse flow can be reduced.

The results (result 5) and (result 6) are approximately the same. As can be seen from this, there is no great difference between the case where the rectifying plate 120 shown in fig. 4 is provided and the case where the rectifying plate 120 is divided, that is, the case where the 1 st rectifying plate 120A and the 2 nd rectifying plate 120B shown in fig. 6 are provided, and there is little influence on whether the rectifying plate 120 is divided. Therefore, whether or not to divide the rectifying plate 120 may be determined appropriately according to the shape and the molding method of the intake duct 140.

(results 4 to 6) compared with (result 3), the standard deviation of the output of the air flow meter 25 at the throttle opening degree of α [ ° ] is small. As can be seen from this, compared with the case where one rectifying plate 120 is provided (see fig. 3), the swirl component of the reverse flow can be reduced more in the case where a pair of rectifying plates are provided (see fig. 5).

In addition, since the standard deviation of the output of the airflow meter 25 is smaller in (result 3) compared to (result 2), the swirl component of the reverse flow can be more effectively reduced when the 1-piece flow plate 120 is provided, compared to the case where the distance between the airflow meter 25 and the compressor 101 is extended by 1.2 times.

As described above, according to the present embodiment, the swirl component of the reverse flow from the impeller 11 can be effectively reduced by providing the rectifying plate 120, and the accuracy of the air flow meter 25 can be improved. Further, the liquid contained in the blow-by gas can be prevented from adhering to the flow regulating plate 120, and contamination in the intake passage 111 can be prevented.

In the above-described embodiment, the example in which the large-cross-section flow passage 152 has a rectangular flow passage cross section has been described, but the present invention is not limited to this. For example, the large-cross-section flow channel 152 may have a circular flow channel cross section. In the above embodiment, the example in which the rectifying plate 120 is provided only on the downstream side of the ventilation flow path 112 has been described, but the present invention is not limited to this. For example, the flow regulating plate 120 may be formed such that one end (right end in the drawing) in the longitudinal direction of the flow regulating plate 120 shown in fig. 4 is positioned on the intake air upstream side of the ventilation flow path 112. Further, in the above embodiment, the example in which the lower end portion of the rectifying plate 120 extending downward from the top plate 142 is positioned above the small cross-sectional flow passage 151 constituting the inlet of the impeller chamber 110 has been described, but the present invention is not limited thereto. The flow regulating plate 120 may be formed such that the lower end portion of the flow regulating plate 120 overlaps the small cross-sectional flow passage 151 when viewed from the intake upstream side along the axis CL of the impeller 11. In the above embodiment, the ventilation flow path 112 is provided so as to intersect the axis line CL of the impeller 11, but the ventilation flow path may be provided so as to be offset from the axis line CL as long as the rectifying plate is disposed so as to be offset from the inlet of the ventilation flow path.

One or more of the above embodiments and modifications may be arbitrarily combined, or modifications may be combined with each other.

According to the present invention, surging can be suppressed by the rectifying plate, and liquid contained in blow-by gas can be suppressed from adhering to the rectifying plate.

While the preferred embodiments of the present invention have been described, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the scope of the disclosure of the following claims.

Claims

1. A compressor unit, characterized by having:

a compressor (101) that compresses intake air of the internal combustion engine using an impeller (11);

an impeller chamber (110) that houses the impeller (11) so that the impeller (11) can rotate;

an intake flow path (111) that extends along the axis of the impeller (11) and introduces intake air into the impeller chamber (110);

a ventilation flow path (112) that introduces blow-by gas of the internal combustion engine into the intake flow path (111); and

a flow regulating plate (120) provided along the axis of the impeller (11) between an inlet (112a) of the ventilation flow path (112) that faces the intake flow path (111) and the impeller chamber (110),

the rectifying plate (120) is provided at a position shifted to one side and a position shifted to the other side in a direction orthogonal to the axis of the impeller (11) with respect to an inlet (112a) of the ventilation flow path (112),

the rectifying plate (120) is configured to block a swirling flow that flows from the impeller chamber (110) back to the intake flow path (111) from flowing toward an inlet (112a) of the ventilation flow path (112).

2. Compressor unit according to claim 1,

the rectifying plate (120) is provided to extend downward from a top plate (142) forming the intake passage (111), and a tip end portion of the rectifying plate (120) is located above an inlet of the impeller chamber (110).

3. Compressor unit according to claim 1,

the intake flow path (111) has a 1 st flow path (151) constituting an inlet of the impeller chamber (110), a 2 nd flow path (152) provided upstream of the 1 st flow path (151) and having a larger flow path cross-sectional area than the 1 st flow path (151), and a tapered portion (153) provided between the 1 st flow path (151) and the 2 nd flow path (152) and inclined from the 2 nd flow path (152) to the 1 st flow path (151).

4. Compressor unit according to claim 3,

the rectifying plate (120) is disposed radially outward of the circumferential surface of the 1 st flow path (151).

5. Compressor unit according to claim 3 or 4,

further comprising a 1 st member (140a) constituting the 2 nd flow path (152), a 2 nd member (140b) constituting the 1 st flow path (151) and the tapered portion (153),

the rectifying plate (120) is attached to the inner peripheral surface of the 1 st member (140 a).

6. Compressor unit according to any one of claims 1 to 4,

the ventilation flow path (112) is provided so as to intersect the axis (CL) of the impeller (11).

7. Compressor unit according to claim 5,