JP2012097662A - Variable diffuser of centrifugal compressor for supercharger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a variable diffuser that reduces driving force required for an actuator, easily ensures a connection space for a bearing housing with respect to a base, prevents a compressed air from losing speed, and improves the supercharging efficiency of a centrifugal compressor.SOLUTION: A plurality of vanes 6 include an inner peripheral end 61 rotatably supported with respect to a base inner peripheral edge 41 in a base 4, and an outer peripheral end 62 provided with a shaft 621 movable along a guide groove 51 inclined relative to the circumferential direction C of an interlocking ring 5. The variable diffuser 3 is configured to change the inclination angle α of each of the vanes 6, by rotationally driving the interlocking ring 5 with respect to the base 4 so that the shaft 621 in the outer peripheral end 62 of the each of the vanes 6 moves along the guide groove 51 and each of the vanes 6 turns about the inner peripheral end 61.

Description

  The present invention relates to a variable diffuser in which a tilt angle of a plurality of vanes provided in a diffuser portion can be adjusted in a centrifugal compressor for a supercharger.

In a centrifugal compressor constituting a supercharger (turbocharger) in an internal combustion engine, a diffuser portion that allows compressed air discharged from a compressor impeller to pass through is used to reduce the velocity energy of the compressed air and increase the pressure recovery amount. A vane (blade) is provided.
For example, in the turbocharger compressor provided with the surge suppression means of Patent Document 1, an annular diffuser row is provided on the periphery of the compressor rotor, and the diffuser row is tilted so that the tilt angle can be variably adjusted. It is constituted by a row of vanes provided. The supercharging compressor exhibits higher operating efficiency while suppressing surges over the entire speed range from the low speed range to the high speed range.

  Further, for example, in the compressor of the exhaust turbocharger disclosed in Patent Document 2, a plurality of guide vanes arranged in the diffuser are connected to each other via an arm, and one of the arms is rotated by an air cylinder. It is disclosed that any one of the guide vanes is rotated and the remaining guide vanes are interlocked via the remaining arms. In the low speed region of the engine, the guide vanes protrude into the diffuser and the angle is variably adjusted to improve the supercharging efficiency. Further, in the high speed region of the engine, the guide vanes are moved to the storage chamber to prevent the generation of choke and prevent the supercharging efficiency from being lowered.

Further, for example, in the turbocharger control device of Patent Document 3, it is disclosed that each diffuser vane is rotated via each driven arm by rotating a so-called unison ring by an actuator.
Further, for example, in the improved variable geometry assembly for a turbocharger of Patent Document 4, it is disclosed that a ring that is inclined with respect to the circumferential direction of the ring is formed in a ring that engages a plurality of vanes. Yes.

JP 2005-163691 A JP-A 64-66419 JP 2007-132232 A Special table 2007-533912 gazette

  By the way, when the gaps between the plurality of vane tips and the outer periphery of the impeller are increased by the rotation of the vanes, the compressed air turns around the compressor impeller, and the efficiency is lowered. The gap between the vane tip and the outer periphery of the impeller is preferably constant in order to increase the efficiency of the compressor. On the other hand, in the high-speed rotation region of the compressor, the plurality of vanes have the vane inclination angle with respect to the circumferential direction, which is the rotation direction of the compressor impeller, set as close as possible to the normal direction of the compressor impeller, and the swirl speed of the compressed air It is preferable to restore the energy to a higher pressure. Thereby, the supercharging efficiency in a high-speed rotation area | region can be maintained.

However, in Patent Documents 1, 3, and 4, the rotation center of the vane is at an intermediate position between the inner peripheral side end and the outer peripheral side end, and when changing the tilt angle of the vane, A gap between the side end portion and the outer periphery of the compressor impeller changes, and in particular, in the low speed rotation region, rotation stall of the compressed air is likely to occur.
Moreover, in patent document 2, each vane is rotated centering on the shaft provided in the inner peripheral side edge part, and an arm exists in the back surface side of a shaft. For this reason, the arm may interfere with a bearing housing that supports and accommodates the rotation shaft of the compressor impeller. Further, when each vane is rotated around the shaft provided at the inner peripheral end, each vane receives pressure from the fluid (compressed air) and is necessary for driving each vane. The driving force must be increased. Further, if the strength of the inner peripheral side end portion of each vane is improved so as to withstand a large driving force, the inner peripheral side end portion of each vane becomes thick, and the targeted supercharging efficiency may not be obtained.

  The present invention has been made in view of such conventional problems, and can reduce the driving force required for the actuator, can easily secure a connection space of the bearing housing to the base, and can rotate the compressed air. It is intended to provide a variable diffuser of a centrifugal compressor for a supercharger that can suppress the above and improve the supercharging efficiency of the centrifugal compressor.

A first aspect of the present invention is a centrifugal compressor for a supercharger, wherein a plurality of vanes for increasing a pressure recovery amount by reducing a swirling speed of the compressed air in a diffuser portion that allows compressed air discharged from a compressor impeller to pass therethrough. A plurality of vanes arranged in a circumferential direction, and a variable diffuser in which the inclination angle of the plurality of vanes with respect to the circumferential direction can be adjusted,
A base disposed between a compressor housing that houses the compressor impeller and a bearing housing that pivotally supports and accommodates the rotation shaft of the compressor impeller;
An interlocking ring that constitutes a diffuser forming surface located on the opposite side of the diffuser portion from the air flow-in side with respect to the compressor impeller, and that is disposed so as to be rotatable around the compressor impeller with respect to the base; Have
The plurality of vanes are rotatably supported at their inner peripheral side end portions with respect to the base inner peripheral side edge portion of the base, and at the outer peripheral side end portions, guides provided on the interlocking ring. There is a shaft that moves along the groove,
By rotating the interlocking ring with respect to the base, the shaft at the outer peripheral end of each vane moves along the guide groove, and each vane is centered on the inner peripheral end. The variable diffuser of a centrifugal compressor for a supercharger is characterized in that it is configured to rotate and change the inclination angle of each vane (Claim 1).

According to a second aspect of the present invention, in the centrifugal compressor for a supercharger, a plurality of vanes for reducing the swirling speed of the compressed air and increasing the pressure recovery amount in the diffuser portion that allows the compressed air discharged from the compressor impeller to pass therethrough. A plurality of vanes arranged in a circumferential direction, and a variable diffuser in which the inclination angle of the plurality of vanes with respect to the circumferential direction can be adjusted,
A base disposed between a compressor housing that houses the compressor impeller and a bearing housing that pivotally supports and accommodates the rotation shaft of the compressor impeller;
An interlocking ring that constitutes a diffuser forming surface located on the opposite side of the diffuser portion from the air flow-in side with respect to the compressor impeller, and that is disposed so as to be rotatable around the compressor impeller with respect to the base; Have
The plurality of vanes have their inner peripheral side ends rotatably supported with respect to the ring inner peripheral side edge of the interlocking ring, and the outer peripheral side ends of the vanes are connected to the vane in the interlocking ring. Is provided with a relief groove provided along the track of the outer peripheral end formed when rotating about the inner peripheral end, and a shaft moving along the guide groove provided on the base. Yes,
By rotating the interlocking ring with respect to the base, the shaft at the outer peripheral end of each vane moves along the escape groove and the guide groove, and each vane is moved to the inner peripheral end. The variable diffuser of the centrifugal compressor for a supercharger is characterized in that the inclination angle of each vane is changed by rotating around the section (claim 3).

The variable diffuser of the centrifugal compressor for a supercharger according to the first aspect of the present invention enables the interlocking ring to be rotatable with respect to the base disposed between the compressor housing and the bearing housing, and the entire vane is rotated simultaneously by the interlocking ring. It is configured to move.
Specifically, the variable diffuser of the first invention has a base, an interlocking ring, and a plurality of vanes, and the interlocking ring is provided with a guide groove at a position corresponding to the outer peripheral side end of each vane. is there. In addition, the plurality of vanes have their inner peripheral side end portions supported so as to be rotatable with respect to the base inner peripheral side edge portion of the base, and the outer peripheral side end portion has a shaft that moves along the guide groove. Is provided.

  As a result, when the interlocking ring is driven to rotate with respect to the base by the actuator, the shaft at the outer peripheral end of each vane moves along the guide groove and each vane rotates about the inner peripheral end. The inclination angle of the entire vane can be changed. That is, each vane can rotate around the inner peripheral side end by pushing the shaft at the outer peripheral end by the guide groove in the interlocking ring. Therefore, when changing the inclination angle of the vane, the gap between the inner peripheral end of the vane and the outer periphery of the compressor impeller does not expand, and the compressed air swirls around the outer periphery of the compressor impeller many times. Generation | occurrence | production of the rotational stall which arises can be suppressed.

In addition, since the outer peripheral side end of each vane is pushed by the guide groove of the interlocking ring, each vane is driven using a moment arm according to the length of the vane from the inner peripheral end to the outer peripheral end. can do. Thereby, the driving force required for the actuator can be reduced, and the capacity of the actuator to be used can be reduced.
In the present invention, there is no need to provide a member for driving the vane on the back surface side (base arrangement side) with respect to the vicinity of the outer periphery of the compressor impeller and the vicinity of the inner peripheral side end of the vane. The connection space of the bearing housing with respect to the can be easily secured.

When the rotation speed of the compressor impeller increases, the interlocking ring is rotated in one direction by the actuator to change the inclination angle (inclination posture) of the entire vane from a position close to the circumferential direction to a position close to the normal direction. Can be made. On the other hand, when the rotation speed of the compressor impeller is lowered, the interlocking ring is rotated in the other direction by the actuator, and the inclination angle (inclination posture) of the entire vane is changed from a position close to the normal direction to a position close to the circumferential direction. Can be made.
Thereby, the supercharging efficiency by the centrifugal compressor can be improved by changing the inclination angle of the entire vane according to the rotational speed of the compressor impeller.

  Therefore, according to the variable diffuser of the centrifugal compressor for a supercharger according to the first aspect of the present invention, the driving force required for the actuator can be reduced, the space for connecting the bearing housing to the base can be easily secured, and The supercharging efficiency of the centrifugal compressor can be improved by suppressing the rotational stall of the compressed air.

  The variable diffuser of the centrifugal compressor for a supercharger according to the second aspect of the invention also enables the interlocking ring to rotate with respect to the base disposed between the compressor housing and the bearing housing, so that the entire vane can be rotated simultaneously by the interlocking ring. It is configured to move. The second invention differs from the first invention in that the inner peripheral side end of each vane is rotatably supported with respect to the interlocking ring, and the relief groove is formed on the interlocking ring and the base On the other hand, the guide groove is formed.

In the second invention, when the interlocking ring is driven to rotate with respect to the base, the shaft at the outer peripheral side end of each vane moves along the escape groove in the interlocking ring and the guide groove in the base, and each vane is in the inner periphery. The inclination angle of each vane can be changed by rotating around the side end.
That is, when the interlocking ring is rotated, the inner peripheral side end of each vane rotates simultaneously, and the shaft at the outer peripheral end moves along the guide groove in the base and the escape groove in the interlocking ring. It can be rotated around the end. Therefore, when the vane rotates, the gap between the inner peripheral side end of the vane and the outer periphery of the compressor impeller does not expand, and the rotation generated by the compressed air swirling around the outer periphery of the compressor impeller The occurrence of stall can be suppressed.

Further, each vane can be driven using a moment arm having a length from the center of rotation of the interlocking ring to the inner peripheral side end of each vane. Thereby, the driving force required for the actuator can be reduced, and the capacity of the actuator to be used can be reduced.
Also in the present invention, there is no need to provide a member for driving the vane on the back side (base arrangement side) near the outer periphery of the compressor impeller and the vicinity of the inner peripheral side end of the vane. The connection space of the bearing housing with respect to the can be easily secured. Further, similarly to the first invention, the supercharging efficiency by the centrifugal compressor can be improved by changing the inclination angle of the entire vane according to the rotational speed of the compressor impeller.

  Therefore, the variable diffuser of the centrifugal compressor for the supercharger according to the second invention can reduce the driving force required for the actuator, easily secure the space for connecting the bearing housing to the base, and compress the compressor. The supercharging efficiency of the centrifugal compressor can be improved by suppressing the rotational stall of the air.

Explanatory drawing which shows the variable diffuser of the centrifugal compressor for superchargers in the state seen from the front in Example 1. FIG. BRIEF DESCRIPTION OF THE DRAWINGS Sectional explanatory drawing which shows the variable diffuser of the centrifugal compressor for superchargers in the state seen from the side in Example 1. FIG. Sectional explanatory drawing which expands and shows a part of FIG. 2 in Example 1. FIG. Explanatory drawing which shows the variable diffuser of the centrifugal compressor for superchargers in the state seen from the front in Example 2. FIG. Cross-sectional explanatory drawing which shows the variable diffuser of the centrifugal compressor for superchargers in the state seen from the side in Example 2. FIG. Sectional explanatory drawing which expands and shows a part of FIG. 5 in Example 2. FIG.

A preferred embodiment in the first and second inventions described above will be described.
In the first invention, it is preferable that the guide groove is provided to be inclined with respect to the circumferential direction in the interlocking ring.
In the second invention, it is preferable that the guide groove is provided to be inclined with respect to the circumferential direction in the base.
In these cases, each vane can be easily rotated by rotating the interlocking ring.

Hereinafter, embodiments of a variable diffuser of a centrifugal compressor for a supercharger according to the present invention will be described with reference to the drawings.
Example 1
As shown in FIGS. 1 and 2, the variable diffuser 3 of the turbocharger centrifugal compressor 1 of the present example is a diffuser portion that allows compressed air A discharged from the compressor impeller 2 to pass through in the turbocharger centrifugal compressor 1. In FIG. 31, a plurality of vanes 6 for increasing the pressure recovery amount by decreasing the swirling speed of the compressed air A are arranged in the circumferential direction C, and the inclination angle α of the plurality of vanes 6 with respect to the circumferential direction C is adjusted. Made possible.
The variable diffuser 3 has the following base 4 and interlocking ring 5 in addition to the plurality of vanes 6. The base 4 is disposed between the compressor housing 11 that houses the compressor impeller 2 and the bearing housing 12 that supports and supports the rotating shaft 22 of the compressor impeller 2. The interlocking ring 5 constitutes a diffuser forming surface 32 located on the opposite side of the diffuser portion 31 from the side where the air A0 flows with respect to the compressor impeller 2, and can rotate around the compressor impeller 2 with respect to the base 4. It is arranged.

  The plurality of vanes 6 have their inner peripheral side end portions 61 supported so as to be rotatable with respect to the base inner peripheral side edge portion 41 of the base 4. A shaft 621 that moves along a guide groove 51 that is inclined with respect to the circumferential direction C is provided. The variable diffuser 3 rotates the interlocking ring 5 with respect to the base 4 so that the shaft 621 at the outer peripheral side end 62 of each vane 6 moves along the guide groove 51 and each vane 6 is moved to the inner periphery. It is configured to rotate around the side end 61 to change the inclination angle α of each vane 6.

Hereinafter, the variable diffuser 3 of the centrifugal compressor 1 for the supercharger of this example will be described in detail with reference to FIGS.
Here, FIG. 1 is a diagram showing the variable diffuser 1 as viewed from the diffuser forming surface 32 side, and FIG. 2 schematically shows the structure of the base 4, the interlocking ring 5, and the vane 6 in the variable diffuser 1. It is a figure which shows the cross section cut | disconnected in the position for convenience for description. FIG. 3 is an enlarged view of a part of FIG.

As shown in FIG. 2, the supercharger of this example is used for an automobile turbocharger. The turbocharger generates compressed air A by rotating the compressor impeller 2 disposed coaxially with the rotary shaft 22 provided with the turbine impeller by rotating the turbine impeller using the energy of the exhaust gas. .
The compressor impeller 2 includes a plurality of blades 21 arranged in the circumferential direction C. The compressor housing 11 sucks air A0 from an intake port 111 provided at an axial end of the compressor impeller 2 and converts the air A0 into compressed air A by the compressor impeller 2, and the compressed air A is converted to the outer peripheral side of the compressor impeller 2. The engine is configured to take air from the discharge scroll chamber 112 to the engine via the diffuser portion 31 provided in the engine.

As shown in FIG. 2, the variable diffuser 3 forms a wall surface (diffuser forming surface 32) on the turbine side (or bearing housing 12 side) and a part of the discharge scroll chamber 112 in the diffuser portion 31, and pressure is applied to the diffuser forming surface 32. A plurality of vanes 6 for adjusting the recovery amount are provided.
As shown in FIG. 1, each vane 6 is disposed so as to be inclined in a direction following the direction in which the compressed air A is blown out so that the compressed air A discharged by the rotation of the compressor impeller 2 passes to the outer peripheral side.
As shown in FIG. 3, the base 4 has a disk shape, and is a base outer peripheral side edge 42 positioned on the outermost peripheral side and a base inner peripheral side edge positioned on the inner peripheral side adjacent to the compressor impeller 2. An annular plate-shaped interlocking ring 5 is rotatably disposed in an annular recess 43 formed between the annular recess 41 and the annular recess 43.

  As shown in FIG. 1, the interlocking ring 5 is provided with a linear guide groove 51 that is inclined with respect to the circumferential direction C at a position corresponding to the outer peripheral end 62 of each vane 6. The guide groove 51 follows the track of the outer peripheral end 62 when each vane 6 rotates (changes direction) about the inner peripheral end 61 when the interlocking ring 5 is rotated. Is formed.

Although not shown, a drive pin for rotating the interlocking ring 5 by an actuator is attached to the side of the interlocking ring 5 that faces the base 4. And the actuator arrange | positioned at the outer peripheral side of the bearing housing 12 can rotate the interlocking ring 5 via a link and a drive pin. In addition, when the interlocking ring 5 rotates, the base 4 can be formed with an elongated hole in the circumferential direction C for avoiding the interference of the drive pin.
Various actuators such as a negative pressure type and an electric type can be used as the actuator. When a negative pressure type actuator is used, a suction force acts when the engine is started, and the inclination angle α (inclination posture) of each vane 6 is temporarily maintained at a position 601 close to the circumferential direction C by this suction force. can do.

As shown in FIG. 3, a rotation fulcrum 611 that rotatably engages with a support hole 411 provided in the base inner peripheral edge 41 of the base 4 is provided at the inner peripheral end 61 of each vane 6. It is. The rotation fulcrum part 611 can be constituted by a bearing, a roller, or the like.
Further, the interlocking ring 5 is prevented from coming off by a guide 44 provided on the outer periphery of the annular recess 43 of the base 4, and is guided to rotate by a guide roller 45 provided at the bottom of the annular recess 43.

The variable diffuser 3 of the centrifugal compressor 1 for the supercharger of this example makes the interlocking ring 5 rotatable with respect to the base 4 disposed between the compressor housing 11 and the bearing housing 12. 6 is configured to rotate at the same time.
Specifically, the variable diffuser 3 of this example includes a base 4, an interlocking ring 5, and a plurality of vanes 6, and the interlocking ring 5 has a position corresponding to the outer peripheral side end 62 of each vane 6. The guide groove 51 is provided so as to be inclined with respect to the circumferential direction C which is the rotation direction of the compressor impeller 2. The plurality of vanes 6 have their inner peripheral side end portions 61 supported so as to be rotatable with respect to the base inner peripheral side edge portion 41 of the base 4, and the outer peripheral side end portions 62 have guide grooves. A shaft 621 that moves along the shaft 51 is provided.

  Thereby, when the interlocking ring 5 is rotationally driven with respect to the base 4 by the actuator, the shaft 621 at the outer peripheral side end 62 of each vane 6 moves along the guide groove 51 and each vane 6 is at the inner peripheral end. The inclination angle α of the entire vane 6 can be changed by rotating around 61. That is, each vane 6 can rotate around the inner peripheral end 61 when the shaft 621 at the outer peripheral end 62 is pushed by the guide groove 51 in the interlocking ring 5. Therefore, when the inclination angle α of the vane 6 is changed, the gap X between the inner peripheral side end 61 of the vane 6 and the outer periphery of the compressor impeller 2 is not enlarged, and the compressed air A is not absorbed by the compressor impeller 2. It is possible to suppress the occurrence of rotational stall caused by turning the outer periphery many times.

Further, since the outer peripheral side end 62 of each vane 6 is pushed by the guide groove 51 of the interlocking ring 5, a moment arm according to the length of the vane 6 from the inner peripheral end 61 to the outer peripheral end 62 is used. Thus, each vane 6 can be driven. Thereby, the driving force required for the actuator can be reduced, and the capacity of the actuator to be used can be reduced.
In this example, a member for driving the vane 6 is provided on the back surface side (the side on which the base 4 is disposed) with respect to the vicinity of the outer periphery of the compressor impeller 2 and the vicinity of the inner peripheral side end 61 of the vane 6. There is no need, and the connection space S of the bearing housing 12 to the base 4 can be easily secured.

  As shown in FIG. 1, when the rotational speed of the compressor impeller 2 increases, the interlock ring 5 is rotated in one direction by the actuator so that the inclination angle α (inclination posture) of the entire vane 6 is close to the circumferential direction C. To a position 602 close to the normal direction. The flow of the compressed air A at this time is indicated by an arrow A2. Moreover, in the figure, the state when the interlocking ring 5 is rotated in one direction (indicated by arrow D) is shown. Further, the rotation direction of the compressor impeller 2 is indicated by an arrow T.

On the other hand, when the rotation speed of the compressor impeller 2 decreases, the interlocking ring 5 is rotated in the other direction by the actuator, and the inclination angle α (inclination posture) of the vane 6 as a whole is changed from the position 602 close to the normal direction to the circumferential direction. The position can be changed to a position 601 close to C. The flow of the compressed air A at this time is indicated by an arrow A1.
Thereby, the supercharging efficiency by the centrifugal compressor can be improved by changing the inclination angle α of the entire vane 6 according to the rotational speed of the compressor impeller 2.

  Therefore, according to the variable diffuser 3 of the centrifugal compressor 1 for the supercharger of this example, it is possible to reduce the driving force necessary for the actuator and easily secure the connection space S of the bearing housing 12 to the base 4. It is possible to suppress the rotational stall of the compressed air A and improve the supercharging efficiency of the centrifugal compressor.

(Example 2)
This example is an example in which the structure for rotating the plurality of vanes 6 is changed with respect to the variable diffuser 3 shown in the first embodiment.
As shown in FIGS. 4 and 5, the variable diffuser 3 of the turbocharger centrifugal compressor 1 of the present example also rotates the interlocking ring 5 with respect to the base 4 disposed between the compressor housing 11 and the bearing housing 12. The entire vane 6 is simultaneously rotated by the interlocking ring 5. And in the variable diffuser 3 of this example, the inner peripheral side edge part 61 of each vane 6 is supported so that rotation with respect to the interlocking ring 5, and the escape groove | channel 52 is formed with respect to the interlocking ring 5, and the base 4 In contrast, a guide groove 46 is formed.

  Specifically, as shown in FIG. 6, the variable diffuser 3 of this example is provided between a compressor housing 11 that houses the compressor impeller 2 and a bearing housing 12 that pivotally supports and accommodates the rotating shaft 22 of the compressor impeller 2. And the interlocking ring 5 disposed so as to be rotatable around the compressor impeller 2 with respect to the base 4. The interlocking ring 5 constitutes a diffuser forming surface 32 located on the opposite side of the diffuser portion 31 to the side where air flows into the compressor impeller 2.

As shown in FIG. 4, the plurality of vanes 6 have their inner peripheral side end portions 61 supported so as to be rotatable with respect to the ring inner peripheral side edge portion 53 in the interlocking ring 5, and their outer peripheral side end portions 62. Is provided with a shaft 621. The shaft 621 in each vane 6 includes a relief groove 52 provided along the track of the outer peripheral end 62 formed when the vane 6 rotates about the inner peripheral end 61 in the interlocking ring 5, and a base 4 moves along a guide groove 46 that is inclined with respect to the circumferential direction C.
In the variable diffuser 3 of this example, when the interlocking ring 5 is rotationally driven with respect to the base 4, the shaft 621 at the outer peripheral end 62 of each vane 6 moves along the escape groove 52 and the guide groove 46. At the same time, each vane 6 rotates around the inner peripheral end 61 to change the inclination angle α of each vane 6.

In this example, since the inner peripheral side end 61 of each vane 6 is supported so as to be rotatable with respect to the interlocking ring 5, when the interlocking ring 5 is rotationally driven with respect to the base 4, The position of the outer peripheral side end 62 of each vane 6 is changed by the provided guide grooves 46.
When the interlocking ring 5 of this example is rotated, each vane 6 moves while the inner peripheral side end portion 61 is simultaneously rotated and the shaft 621 at the outer peripheral side end portion 62 is guided by the guide groove 46 in the base 4. The inner peripheral side end 61 can be turned around. Further, the shaft 621 at the outer peripheral side end 62 moves along the relief groove 52 in the interlocking ring 5. Therefore, when the vane 6 rotates, the gap X between the inner peripheral side end 61 of the vane 6 and the outer periphery of the compressor impeller 2 does not expand, and the compressed air A does not move around the outer periphery of the compressor impeller 2. It is possible to suppress the occurrence of rotational stall caused by turning the circumference.

Further, each vane 6 can be driven using a moment arm having a length from the rotation center of the interlocking ring 5 to the inner peripheral side end portion 61 of each vane 6. Thereby, the driving force required for the actuator can be reduced, and the capacity of the actuator to be used can be reduced.
Also in this example, a member for driving the vane 6 is provided on the back surface side (the side where the base 4 is disposed) with respect to the vicinity of the outer periphery of the compressor impeller 2 and the vicinity of the inner peripheral side end 61 of the vane 6. There is no need, and the connection space S of the bearing housing 12 to the base 4 can be easily secured. Similarly to the first embodiment, the supercharging efficiency by the centrifugal compressor can be improved by changing the inclination angle α of the entire vane 6 in accordance with the rotational speed of the compressor impeller 2.
Also in this example, other configurations are the same as those of the first embodiment, and the same effects as those of the first embodiment can be obtained.

DESCRIPTION OF SYMBOLS 1 Centrifugal compressor 11 for turbochargers 11 Compressor housing 12 Bearing housing 2 Compressor impeller 3 Variable diffuser 31 Diffuser part 32 Diffuser formation surface 4 Base 46 Guide groove 5 Interlocking ring 51 Guide groove 52 Relief groove 6 Vane 61 Inner peripheral side end 62 Outer end 621 Shaft

Claims (4)

In a centrifugal compressor for a supercharger, a plurality of vanes for reducing a swirling speed of the compressed air and increasing a pressure recovery amount are directed in a circumferential direction to a diffuser portion that allows compressed air discharged from a compressor impeller to pass therethrough. A variable diffuser in which a plurality of the vanes are arranged and the inclination angle with respect to the circumferential direction of the plurality of vanes is adjustable.
A base disposed between a compressor housing that houses the compressor impeller and a bearing housing that pivotally supports and accommodates the rotation shaft of the compressor impeller;
An interlocking ring that constitutes a diffuser forming surface located on the opposite side of the diffuser portion from the air flow-in side with respect to the compressor impeller, and that is disposed so as to be rotatable around the compressor impeller with respect to the base; Have
The plurality of vanes are rotatably supported at their inner peripheral side end portions with respect to the base inner peripheral side edge portion of the base, and at the outer peripheral side end portions, guides provided on the interlocking ring. There is a shaft that moves along the groove,
By rotating the interlocking ring with respect to the base, the shaft at the outer peripheral end of each vane moves along the guide groove, and each vane is centered on the inner peripheral end. A variable diffuser of a centrifugal compressor for a supercharger, wherein the variable diffuser is configured to rotate and change an inclination angle of each vane.   The variable diffuser of the centrifugal compressor for a supercharger according to claim 1, wherein the guide groove is provided to be inclined with respect to a circumferential direction in the interlocking ring. Variable diffuser of the machine. In a centrifugal compressor for a supercharger, a plurality of vanes for reducing a swirling speed of the compressed air and increasing a pressure recovery amount are directed in a circumferential direction to a diffuser portion that allows compressed air discharged from a compressor impeller to pass therethrough. A variable diffuser in which a plurality of the vanes are arranged and the inclination angle with respect to the circumferential direction of the plurality of vanes is adjustable.
A base disposed between a compressor housing that houses the compressor impeller and a bearing housing that pivotally supports and accommodates the rotation shaft of the compressor impeller;
An interlocking ring that constitutes a diffuser forming surface located on the opposite side of the diffuser portion from the air flow-in side with respect to the compressor impeller, and that is disposed so as to be rotatable around the compressor impeller with respect to the base; Have
The plurality of vanes have their inner peripheral side ends rotatably supported with respect to the ring inner peripheral side edge of the interlocking ring, and the outer peripheral side ends of the vanes are connected to the vane in the interlocking ring. Is provided with a relief groove provided along the track of the outer peripheral end formed when rotating about the inner peripheral end, and a shaft moving along the guide groove provided on the base. Yes,
By rotating the interlocking ring with respect to the base, the shaft at the outer peripheral end of each vane moves along the escape groove and the guide groove, and each vane is moved to the inner peripheral end. A variable diffuser of a centrifugal compressor for a supercharger, characterized in that the tilt angle of each vane is changed by rotating around the section.   The variable diffuser of the centrifugal compressor for a supercharger according to claim 3, wherein the guide groove is provided to be inclined with respect to a circumferential direction in the base. Variable diffuser.

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