JP2010071140A - Variable displacement turbocharger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a variable capacity turbocharger reducing cost by making an actuator driving blades unnecessary, and making a complicated control logic unnecessary. <P>SOLUTION: Four fan shape blades 61 which can do opening/closing action to a surface perpendicularly crossing the direction of flow of air are provided in a compressor lead-in pipe 11. Each blade 61 is fixed on rotatable shafts 62 projecting toward an axis from an outer circumference surface of the compressor lead-in pipe 11, respectively. Coil springs 65 energizing each blade 61 in a blocking direction are wound around at a radially outer end of each shaft 62. Each blade 61 is moved to a fully closed position by each coil spring 65 when air flow from a compressor lead-in port 11a does not exist at all. When air flow increases, each blade 61 is moved to a fully opened position, resisting energizing force to a fully closed side by each coil spring 65 while keeping balance with increased quantity of air. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a variable capacity turbocharger in which the flow rate of air compressed based on the rotation of a rotor provided in an intake passage of an engine is variable depending on the opening of a guide that can be opened and closed in the air flow direction. is there.

  Conventionally, as this type of variable capacity turbocharger, a guide vane that can be projected and retracted is provided in an annular passage that leads from the rotor of the compressor to the scroll portion downstream in the air flow direction, and this guide vane is used as a spotted passage. Is known in which the flow rate of compressed air is made variable based on the rotation of the rotor by projecting or retracting (see Patent Document 1, for example). In this case, an actuator for projecting or retracting the guide vane into the annular passage and a controller for operating the actuator in accordance with the operating state of the engine are provided.

As another variable capacity turbocharger, an annular passage that leads from the scroll portion to the rotor of the exhaust turbine downstream in the flow direction of the exhaust gas from the direction substantially perpendicular to the flow direction of the exhaust gas on the annular passage. A diffuser vane fixed to the projecting pivotable shaft is provided, and the opening of the diffuser vane can be adjusted by rotating the pivoting ring. In some cases, the flow rate of the exhaust gas is made variable by adjusting (see, for example, Patent Document 2). In this case, the rotation ring is connected to an actuator via a rod, and the rotation ring is rotated by operating this actuator according to the operating state of the engine.
JP-A-8-254127 Japanese Utility Model Publication No. 63-115532

  However, the above-mentioned conventional former requires an actuator that projects or retracts a guide, such as a guide vane, in order to make the air flow rate variable. On the other hand, in the latter case of the prior art, an actuator for opening and closing a guide such as a diffuser vane is required to make the flow rate of the exhaust gas variable. For this reason, in any case, an actuator is required and the cost increases.

  Moreover, in order to operate such an actuator in accordance with the operating state of the engine, complicated control logic is indispensable, and countermeasures have been eagerly desired.

  The present invention has been made in view of the above points, and an object of the present invention is to eliminate the need for an actuator that drives a guide, thereby reducing the cost and making a complicated control logic unnecessary. It is to provide a variable capacity turbocharger.

  In order to achieve the above object, according to the present invention, the flow rate of air compressed based on the rotation of a rotor provided in an intake passage of an engine is variable depending on the opening of a guide that can be opened and closed in the air flow direction. A variable capacity turbocharger is assumed. Further, the guide is fixed to a rotatable shaft protruding from a direction substantially perpendicular to the air flow direction on the intake passage. The shaft is urged against the fully closed side while the guide is against the urging force toward the fully closed side while balancing the increased amount of air as the air flow rate increases. Biasing means is provided for operating to the fully open position.

  Due to this specific matter, the guide urged to the fully closed side by the urging means is fully opened against the urging force to the fully closed side while balancing the increased amount of air as the air flow rate increases. Since it moves to the position, the force generated in the guide by the fluid force of air, that is, the force corresponding to the square of the approximate air flow rate (force to open the guide) and the biasing force of the biasing means are balanced. At this position, the opening of the guide is determined. In other words, if the air flow rate is small, the opening of the guide will be small, and the surge flow rate, which is the critical flow rate at which surging will occur, will be reduced. Is hardly received.

  As a result, the opening degree of the guide is optimally set according to the air flow rate, an actuator for operating the guide is not required, and the cost can be reduced. This also eliminates the need for a variable capacity turbocharger system.

  In particular, the following configurations are listed as specifying the attachment of the guide to the shaft. That is, the guide is attached so as to be asymmetric with respect to the shaft when viewed from the air flow direction.

  Due to this specific matter, when air is blown onto the guide, the air flow acts on a large area of the guide that is asymmetrical with respect to the shaft when viewed from the air flow direction, and the guide acts like a weathercock with the shaft as a fulcrum. It is easy to operate on the open side. For this reason, the guide smoothly moves to the open side according to the air flow rate, and the guide can be opened with high accuracy.

  In particular, the following configuration is listed as one for specifying the mounting position of the guide. That is, the guide is provided upstream of the rotor in the air flow direction.

  Due to this specific matter, when the air flow rate is small, the opening of the guide becomes small, and a strong inlet swirl flow is generated, so that the surge flow rate can be reduced. When the air flow rate increases, the opening degree of the guide is determined at a position balanced with the urging force of the urging means, and the surge flow rate can be changed according to the opening degree. On the other hand, when the flow rate of air is large, the opening of the guide is increased, and no inlet swirl flow is generated, which is hardly affected by the guide and is equivalent to a normal turbocharger without a guide. It becomes possible to demonstrate the performance of.

  On the other hand, when the guide is provided in the annular passage that leads from the rotor to the scroll portion on the downstream side in the air flow direction, if the air flow rate is small, the opening of the guide becomes small and the surge The flow rate can be reduced. When the air flow rate increases, the opening degree of the guide is determined at a position balanced with the urging force of the urging means, and the surge flow rate can be changed according to the opening degree. On the other hand, when the air flow rate is high, the opening of the guide becomes large, and it is hardly affected by the guide, and the choke flow rate is secured and the performance equivalent to that of a normal turbocharger without a guide is demonstrated. It becomes possible to do.

  In short, the guide is generated by the fluid force of air by operating the guide to the fully open position against the urging force toward the fully closed side while balancing with the increased amount of air as the air flow rate increases. The opening of the guide is determined at a position where the force for opening the guide and the biasing force of the biasing means are balanced. For this reason, when the flow rate of air is small, the opening degree of the guide is reduced and the surge flow rate is reduced. On the other hand, when the air flow rate is high, the opening degree of the guide is increased and is hardly affected by the guide. As a result, the opening of the guide can be set optimally according to the air flow rate, the actuator for operating the guide can be eliminated, the cost can be reduced, and the variable capacity turbo can be eliminated without complicated control logic. The charger system can be simplified.

  An embodiment of a variable capacity turbocharger according to the present invention will be described with reference to the drawings.

  FIG. 1 shows a cross section of a variable capacity turbocharger according to a first embodiment of the present invention.

  The compressor housing 10 of the variable capacity turbocharger 1 is provided with a compressor introduction pipe 11 (intake passage) through which a compressor introduction port 11a opens, a compressor discharge port 12, and a ring-shaped compressor side scroll 13. The compressor-side scroll 13 extends from the position adjacent to the compressor discharge port 12 along the outer periphery of the compressor housing 10 and communicates with the compressor discharge port 12. And the compressor side scroll 13 is comprised so that a cross-sectional area may be expanded gradually as the compressor discharge port 12 is approached.

  A lubricant introduction port 31 is formed on the outer periphery of the bearing housing 20 adjacent to the compressor housing 10. The lubricating oil introduction port 31 communicates with branch oil passages 35a, 35b, and 35c through an oil passage 35 formed in the axial direction. Lubricating oil supplied from an oil pump (not shown) is supplied to the shaft 36 and the shaft 36. The bearings 36a, 36b, 36c, 36d, 36e to be supported are supplied to the sliding surfaces. The lubricating oil supplied to the sliding surface is discharged from the lubricating oil discharge port 37 a through a space 37 formed inside the bearing housing 20. Reference numeral 38 denotes a cooling water passage for cooling the variable capacity turbocharger 1, and 39 denotes a plate seal. In addition, 20a is one piece of the bearing housing 20 divided | segmented in order to shape | mold each site | part provided in the bearing housing 20. FIG.

  An exhaust gas inlet 34 and an exhaust gas outlet 32 are formed in the turbine housing 30 adjacent to the bearing housing 20. The turbine housing 30 is provided with a ring-shaped turbine-side scroll 33. The turbine-side scroll 33 extends from the position adjacent to the exhaust gas introduction port 34 along the outer periphery of the turbine housing 30 and communicates with the exhaust gas discharge port 32. The turbine-side scroll 33 is configured to gradually reduce the cross-sectional area as it approaches the exhaust gas introduction port 34.

  A compressor rotor 43 (rotor) is rotatably and integrally attached to the shaft 36 supported by the bearings 36a, 36b, 36c, 36d, and 36e of the bearing housing 20 by bolts 41 and nuts 42 at the end on the compressor housing 10 side. On the other hand, the turbine rotor 44 is integrally attached to the turbine housing 30 at the end portion thereof. A compressor side blade 45 and a turbine side blade 46 extending in the radial direction are attached to the compressor rotor 43 and the turbine rotor 44, respectively, and the compressor rotor 43 is rotated integrally by rotating the turbine rotor 44. It has become. A compressor-side annular passage 14 (annular passage) that communicates with the compressor-side scroll 13 is provided on the downstream side in the air flow direction of the compressor-side blade 45 of the compressor housing 10.

  The compressor discharge port 12 of the compressor housing 10 communicates with the intake manifold 52 of the engine E through the intake downstream pipe 51. On the other hand, the exhaust gas inlet 34 of the turbine housing 30 communicates with the exhaust manifold 54 of the engine E through the exhaust upstream pipe 53. Then, air from the intake upstream pipe through an air cleaner (not shown) is introduced into the compressor introduction port 11a of the compressor housing 10, and the air introduced from the compressor introduction port 11a is communicated from the compressor introduction tube 11 to the compressor side annular passage 14. Then, the air is guided to the compressor discharge port 12 through the compressor side scroll 13, and is guided from the compressor discharge port 12 to the engine E through the intake downstream pipe 51 and the intake manifold 52. In this case, an intake passage is constituted by the intake upstream pipe, the compressor introduction pipe 11 of the compressor housing 10, the compressor side annular passage 14, the compressor side scroll 13, and the intake downstream pipe.

  As shown in FIGS. 2 and 3, the compressor introduction pipe 11 located upstream of the compressor blade 45 in the air flow direction has four sheets as guides that can be opened and closed in the air flow direction. Fan-shaped blades 61, 61,... Are provided. Each blade 61 is disposed so as to close the compressor introduction pipe 11 having an annular cross section on a plane substantially orthogonal to the air flow direction. Further, each blade 61 is divided every 90 ° around the axis of the compressor introduction pipe 11, and on the compressor introduction pipe 11, a direction substantially perpendicular to the air flow direction, that is, the axis from the outer peripheral surface of the compressor introduction pipe 11. Are fixed to rotatable shafts 62, 62,. The shafts 62 are provided on the outer peripheral surface of the compressor introduction pipe 11 at positions spaced apart by a predetermined distance in the circumferential direction (positions spaced by 90 °). Further, on the shaft core of the compressor introduction pipe 11, a shaft core member 63 is fixed by stays 64, 64,... (Shown in FIG. 3), and the inner ends of the respective shafts 62 are respectively connected to the shaft core member 63. It is supported rotatably. On the other hand, the radially outer end of each shaft 62 is rotatably supported by the compressor introduction pipe 11. Coil springs 65, 65,... As urging means are wound around the radially outer ends of the shafts 62, and the shafts 62 individually block the blades 61 by the coil springs 65. It is energized. Each blade 61 is pivoted to the fully closed position (position shown in FIG. 2) by the urging force of each coil spring 65 when there is no flow rate of air introduced from the compressor introduction port 11a (when the engine E is stopped). On the other hand, when the flow rate of air introduced from the compressor introduction port 11a is increased, the coil springs 65 are fully closed while balancing with the increased amount of air. It operates through a shaft 62 up to the fully open position (position shown in FIG. 3) against the urging force. Each blade 61 is attached to each shaft 62 so as to be asymmetric when viewed from the air flow direction in a state where the blade 61 is operating to the fully closed position. Specifically, each shaft 62 is located at one end in the circumferential direction of each blade 61 (on the upper side shown in FIG. The blades 61 are attached at positions shifted from the left end of the blade 61 by about 20 ° to the other side in the circumferential direction (right side of the upper blade 61 shown in FIG. 2). It is divided into a small area portion 61a on the upstream side in the air flow direction at the position and a large area portion 61b on the other side in the circumferential direction from the shaft 62 of each blade 61 (downstream in the air flow direction at the fully open position). . In this case, each blade 61 is positioned at a fully closed position and a fully open position by a stopper (not shown), and is set to an opening according to the flow rate of air introduced from the compressor inlet 11a between these positions. As shown in FIGS. 4A and 4B, the force (moment) acting on each vane 61 by the fluid force of air, that is, the force according to the square of the approximate flow rate of air from the compressor inlet 11a ( The opening at the position where the force for opening each blade 61) and the biasing force of each coil spring 65 are balanced.

  Next, the operation of the variable capacity turbocharger 1 will be described.

  The exhaust gas introduced from the exhaust gas inlet 34 is guided to the scroll 33 inside the turbine housing 30, and is discharged from the exhaust gas outlet 32 by rotating the turbine rotor 44. The rotation of the turbine rotor 44 is transmitted to the compressor rotor 43 via the shaft 36, and the compressor rotor 43 compresses the intake air (air) guided to the compressor introduction port 11 a, and from the compressor discharge port 12 to the intake downstream pipe 51 and the intake manifold 52. High-density intake air is guided to the engine E through the engine. At this time, each blade 61 urged through the shaft 62 to the fully closed side by each coil spring 65 in the compressor introduction pipe 11 positioned upstream of the compressor side blade 45 in the air flow direction has a flow rate of air. As it increases, it moves toward the fully open position against the urging force of each coil spring 65 toward the fully closed side while balancing with the increased amount of air.

  In the low speed range where the exhaust gas flow rate is small, the rotation of the turbine rotor 44 is small, so the rotation of the compressor rotor 43 via the shaft 36 is also small, and the flow rate of air from the compressor inlet 11 a guided by the compressor rotor 43. Less. At this time, each blade 61 urged toward the fully closed side by the coil spring 65 has a low air flow rate, and thus counteracts the urging force toward the fully closed side while balancing the low air flow rate. It moves slightly toward the fully open position and is set to a slight opening. For this reason, a strong inlet swirl flow is generated by the air passing through a slight gap between the blades 61.

  On the other hand, in the high speed region where the exhaust gas flow rate is large, the rotation of the turbine rotor 44 increases, so the rotation of the compressor rotor 43 via the shaft 36 also increases, and the air from the compressor introduction port 11a guided by the compressor rotor 43 is increased. The flow rate also increases. At this time, each blade 61 urged toward the fully closed side by the coil spring 65 resists the urging force toward the fully closed side while balancing with the increased air flow rate because the air flow rate increases. As a result, it moves greatly toward the fully open position and is set to a large opening. For this reason, the inlet swirl flow is not generated by the air passing between the blades 61 set to a large opening degree without any trouble.

  Thus, each blade 61 urged toward the fully closed side by the coil spring 65 resists the urging force toward the fully closed side while balancing with the increased amount of air as the air flow rate increases. Since it operates to the fully open position side, the force acting on each blade 61 by the fluid force of air, that is, the force corresponding to the square of the approximate flow rate of air (the force for opening each blade 61), and the coil spring 65 The opening degree of each blade 61 is determined at a position balanced with the urging force. In short, if the flow rate of air is small, the opening degree of each blade 61 becomes small, and a strong inlet swirl flow is generated to reduce the surging flow rate, which is the limit flow rate at which surging occurs. When the air flow rate increases, the opening degree of each blade 61 is determined at a position balanced with the urging force of the coil spring 65, and the surge flow rate changes according to the opening degree. On the other hand, if the flow rate of air is large, the opening degree of each blade 61 is increased, the inlet swirl flow is not generated, and is hardly affected by each blade 61. The same performance as a normal turbocharger not provided with each blade 61 on the upstream side in the direction is exhibited.

  Thereby, the opening degree of each blade 61 is optimally set according to the flow rate of air, an actuator for operating each blade 61 is not required, and the cost can be reduced. Since the control logic is not required, the system of the variable capacity turbocharger 1 can be simplified.

  In addition, each shaft 62 is attached to each blade 61 at a position that is phased approximately 20 ° from one circumferential end to the other circumferential side, and each blade 61 is located in a small area on the circumferential one side from the shaft 62. 61a and a large area portion 61b on the other side in the circumferential direction are divided, so that when air from the compressor introduction port 11a is blown to each blade 61, an air flow acts on the large area portion 61b of each blade 61. Thus, each blade 61 is easy to operate on the open side like a weathercock with the shaft 62 as a fulcrum. For this reason, each blade | wing 61 operate | moves smoothly according to the flow volume of air, and can open | release each blade | wing 61 accurately.

  Next, a second embodiment of the present invention will be described with reference to FIGS.

  In this embodiment, the guide mounting position and configuration are changed. In addition, the structure other than a guide is the same as that of the said Example 1, The same code | symbol is attached | subjected about the same part and the detailed description is abbreviate | omitted.

  That is, in this embodiment, a plurality of diffuser vanes 71, 71,... As guides are provided downstream of the compressor side blade 45 in the air flow direction. The diffuser vanes 71 are arranged at predetermined intervals in the circumferential direction of the compressor-side annular passage 14 having an annular shape as an intake passage. Each diffuser vane 71 is fixed to a rotatable shaft 72, 72,... Provided at predetermined intervals in the circumferential direction of the compressor-side annular passage 14, respectively. Each shaft 72 extends in a direction substantially orthogonal to the flow direction of air flowing in the outer circumferential direction from the axial center side of the compressor introduction pipe 11 in the compressor side annular passage 14, that is, substantially parallel to the axial center of the compressor introduction pipe 11. The side annular passage 14 is penetrated and both ends thereof are rotatably supported by the compressor housing 10 and the bearing housing 20, respectively. Further, coil springs 73, 73,... As urging means are wound around the end of each shaft 72 on the compressor housing 10 side (the left end in FIG. 5), and each diffuser vane 71 is closed by each coil spring 73. Each direction is individually energized. Then, as shown in FIG. 6, each diffuser vane 71 is in a fully closed position (when the engine E is stopped) by the biasing force of each coil spring 73 when there is no flow rate of air introduced from the compressor introduction port 11a. 6), the flow rate of air introduced from the compressor inlet 11a increases as the flow rate of the air introduced from the compressor inlet 11a increases as shown in FIG. In order to counteract the urging force of each coil spring 73 toward the fully closed side, the actuator moves to the fully open position (position shown in FIG. 7) via the shaft 72. Each diffuser vane 71 is attached to each shaft 72 so as to be asymmetric when viewed from the air flow direction in a state where the diffuser vane 71 is operating to the fully closed position. Specifically, each shaft 72 is attached to the upstream side in the air flow direction (closer to the compressor rotor 43 side) in the state where each diffuser vane 71 is moved to the fully open position in the compressor-side annular passage 14, and each diffuser vane is A small area portion 71a on the upstream side in the air flow direction (compressor rotor 43 side) from the shaft 72 of 71 and a large area portion on the downstream side in the air flow direction (compressor discharge port 12 side) from the shaft 72 of each diffuser vane 71. Each diffuser vane 71 is partitioned into 71b. In this case, each diffuser vane 71 is positioned at a fully closed position and a fully open position by a stopper (not shown), and an opening degree corresponding to the flow rate of air introduced from the compressor introduction port 11a between these positions. The force acting on each diffuser vane 71 by the fluid force, that is, the force corresponding to the square of the approximate flow rate of air from the compressor introduction port 11a (the force for opening each diffuser vane 71), and each coil spring 73 The opening is set at a position balanced with the urging force.

  Next, the operation of the variable capacity turbocharger 1 will be described.

  When the intake air (air) from the compressor introduction port 11 a is compressed by the compressor side blade 45 of the turbine rotor 44 and introduced into the compressor side annular passage 14, the compressor side annular passage 14 is made to be fully closed by the coil springs 73. Each diffuser vane 71 energized via the shaft 72 is fully opened against the energizing force of each coil spring 73 toward the fully closed side while balancing with the increased amount of air as the air flow rate increases. It will move to the position side.

  In the low speed region where the exhaust gas flow rate is small, the rotation of the turbine rotor 44 is small, so the rotation of the compressor rotor 43 via the shaft 36 is also small, and the flow rate of the air compressed by the compressor blade 45 of the compressor rotor 43. Less. Therefore, each diffuser vane 71 urged toward the fully closed side by the coil spring 73 resists the urging force toward the fully closed side while balancing with the low air flow rate because the air flow rate is small. Thus, it moves slightly toward the fully open position and is set to a slight opening. At this time, since the flow angle of the compressor discharge port 12 and the angle of the diffuser vane 71 coincide with each other, the surge flow rate is reduced.

  On the other hand, in the high speed region where the exhaust gas flow rate is large, the rotation of the turbine rotor 44 increases, so the rotation of the compressor rotor 43 via the shaft 36 also increases, and the air compressed by the compressor blades 45 of the compressor rotor 43 increases. The flow rate also increases. At this time, each diffuser vane 71 urged toward the fully closed side by the coil spring 73 increases the air flow rate, so that the increased air flow rate is balanced with the increased air flow rate. On the contrary, it moves greatly to the fully open position side and is set to a large opening. For this reason, the air passes between the diffuser vanes 71 and 71 set to a large opening degree without any trouble, the choke flow rate is ensured, and the performance equivalent to that of a normal turbocharger not provided with each diffuser vane 71 is exhibited. To do.

  In this way, each diffuser vane 71 urged toward the fully closed side by the coil spring 73 resists the urging force toward the fully closed side while balancing the increased amount of air as the air flow rate increases. Therefore, the force acting on each diffuser vane 71 by the fluid force of air, that is, the force corresponding to the square of the approximate flow rate of air (the force for opening each diffuser vane 71), The opening degree of each diffuser vane 71 is determined at a position where the urging force of the coil spring 73 is balanced. In short, if the flow rate of air is small, the opening degree of each diffuser vane 71 becomes small, and the surge flow rate is reduced. When the air flow rate increases, the opening degree of the guide is determined at a position balanced with the urging force of the coil spring 73, and the surge flow rate changes according to the opening degree. On the other hand, if the flow rate of air is large, the opening degree of each diffuser vane 71 becomes large, and it is hardly affected by each diffuser vane 71, a choke flow rate is ensured, and a normal turbo without each diffuser vane 71 is provided. Demonstrates the same performance as a charger.

  As a result, the opening degree of each diffuser vane 71 is optimally set according to the flow rate of air, and an actuator for operating each diffuser vane 71 is not required, and the cost can be reduced. Complex control logic is not required, and the system of the variable capacity turbocharger 1 can be simplified.

  In addition, each shaft 72 is attached to the upstream side in the air flow direction (close to the compressor rotor 43 side) in a state where each diffuser vane 71 is moved to the fully open position in the compressor-side annular passage 14, and the shaft 72 of each diffuser vane 71. Since each diffuser vane 71 is partitioned into a small area portion 71a on the upstream side in the air flow direction and a large area portion 71b on the downstream side in the air flow direction from the shaft 72 of each diffuser vane 71, the compressor rotor When the air compressed by the 43 compressor side blades 45 is blown onto each diffuser vane 71, the air flow acts on the large area portion 71 b of each diffuser vane 71, and each diffuser vane 71 uses the shaft 72 as a fulcrum. It becomes easy to operate on the open side like a weathercock. For this reason, each diffuser vane 71 smoothly moves to the open side according to the flow rate of air, and each diffuser vane 71 can be opened with high accuracy.

  Note that the present invention is not limited to the above-described embodiments, and includes other various modifications. For example, in the first embodiment, 90 around the axis of the compressor introduction pipe 11 as a guide. Although the four fan-shaped blades 61, 61,... Divided at every ° are applied, a plurality of fan-shaped blades divided at predetermined angles around the axis of the compressor introduction pipe may be applied.

  In the first embodiment, each shaft 62 is attached to each blade 61 at a position that is phase shifted by approximately 20 ° from one end in the circumferential direction to the other end in the circumferential direction. It is not limited to a position that is phase shifted by approximately 20 ° from one circumferential end of each blade to the other circumferential direction, and each shaft has an upstream side in the air flow direction with respect to each blade relative to the central position in the circumferential direction. What is necessary is just to attach to the position made to phase to the one circumferential direction which becomes.

  Further, in each of the above embodiments, the blade 61 and the diffuser vane 71 are individually urged through the shafts by the coil springs 65 and 73 respectively provided at the ends of the shafts 62 and 72. And one end of each arm or each diffuser vane is connected to the shaft of each vane or each diffuser vane, and each vane or each diffuser vane is urged to the fully closed side at the other end of the link or arm. It may be connected to a plurality of biasing means smaller than the number. That is, the number of urging means does not necessarily need to match the number of shafts of each blade or each diffuser vane.

It is a vertical side view of the variable capacity | capacitance turbocharger which concerns on Example 1 of this invention. Similarly, it is a longitudinal front view of the vicinity of the compressor housing with each blade fully closed. Similarly, it is a longitudinal side view of the vicinity of the compressor housing with each blade fully opened. FIG. 5 is a diagram for explaining the characteristics of the opening degree of each blade set at a position where the force acting on each blade due to the fluid force of air and the biasing force of the coil spring are balanced, and (a) shows the flow rate of air. On the other hand, it is a characteristic diagram which shows the characteristic of the force which acts on each blade | wing, (b) is a characteristic diagram which shows the characteristic of the urging | biasing force of a coil spring with respect to the opening degree of each blade | wing. It is a vertical side view of the vicinity of the compressor housing of the variable capacity turbocharger according to the second embodiment of the present invention. Similarly, it is a longitudinal front view of the compressor housing in the fully closed state of each diffuser vane. Similarly, it is a longitudinal front view of the compressor housing in a fully opened state of each diffuser vane.

Explanation of symbols

1 Variable capacity turbocharger 10 Compressor housing 11 Compressor introduction pipe (intake passage)
13 Compressor side scroll (scroll)
14 Compressor-side annular passage (intake passage, annular passage)
43 Compressor rotor (rotor)
61 Feather (Guide)
62 Shaft 65 Coil spring (biasing means)
71 Diffuser vane (guide)
72 Shaft 73 Coil spring (biasing means)
E engine

Claims (4)

In a variable capacity turbocharger in which the flow rate of air compressed based on rotation of a rotor provided in an intake passage of an engine is variable depending on the opening degree of a guide that can be opened and closed with respect to the air flow direction.
The guide is fixed to a rotatable shaft that protrudes from a direction substantially orthogonal to the air flow direction on the intake passage,
The shaft urges the guide toward the fully closed side, while the guide is fully opened against the urging force toward the fully closed side while balancing the amount of increase in the air as the air flow rate increases. A variable-capacity turbocharger characterized in that an urging means for operating to a position is provided. The variable capacity turbocharger according to claim 1,
The variable capacity turbocharger, wherein the guide is attached to the shaft so as to be asymmetrical when viewed from the air flow direction. In the variable capacity turbocharger according to claim 1 or 2,
The variable capacity turbocharger, wherein the guide is provided upstream of the rotor in the air flow direction. In the variable capacity turbocharger according to claim 1 or 2,
The variable capacity turbocharger, wherein the guide is provided in an annular passage that leads from the rotor to a scroll downstream in the air flow direction.

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