JP6757281B2 - Turbocharger housing and its manufacturing method - Google Patents

Description

The present invention relates to a turbocharger housing and a method for manufacturing the same.

A turbocharger mounted on an internal combustion engine of an automobile or the like has a compressor impeller and a turbine impeller, and these are housed in a housing. The compressor impeller is arranged in an air flow path formed inside the housing. The air flow path has an intake port for sucking air toward the compressor impeller, a diffuser passage through which the compressed air discharged from the compressor impeller passes, and a discharge scroll chamber through which the compressed air passing through the diffuser passage flows. The discharge scroll chamber discharges compressed air to the internal combustion engine side.

Then, in an internal combustion engine such as an automobile, a blow-by gas recirculation device (hereinafter referred to as PCV) that recirculates blow-by gas (mainly unburned gas) generated in the crankcase to the intake passage to purify the inside of the crankcase and the head cover. ) Is provided. In this case, the oil (oil mist) contained in the blow-by gas may flow out from the PCV to the intake passage on the upstream side of the compressor in the turbocharger.

At this time, if the outlet air pressure of the compressor is high, the outlet air temperature also rises. Therefore, the oil flowing out from the PCV is concentrated and increased in viscosity due to evaporation, so that the diffuser surface of the turbocharger housing and the bearing housing facing the diffuser surface are increased. It may be deposited as a deposit on the surface of the housing. Then, the accumulated deposit narrows the diffuser passage, which may lead to a decrease in the performance of the turbocharger and further a decrease in the output of the internal combustion engine.

Conventionally, in order to prevent the accumulation of deposits in the diffuser passage as described above, the outlet air temperature of the compressor has been suppressed to some extent. Therefore, the performance of the turbocharger could not be fully exhibited, and the output of the internal combustion engine could not be sufficiently increased.

In Patent Document 1, in order to prevent the accumulation of deposits in the diffuser passage, a refrigerant flow path is provided in the housing for the turbocharger, and the refrigerant flows through the refrigerant flow path to pass through the air flow path in the housing. A configuration that suppresses the temperature rise of the compressed air is disclosed. In the configuration disclosed in Patent Document 1, the housing for the turbocharger is formed by the first piece, the second piece, and the third piece, and the refrigerant flow path is defined by assembling the two pieces.

Japanese Unexamined Patent Publication No. 2016-176353

However, in the configuration disclosed in Patent Document 1, in order to maintain the liquidtightness of the refrigerant flow path, a holding portion for holding the O-ring as a sealing member is formed between the first piece and the second piece. At the same time, it is necessary to fit the seal member into the holding portion and further sandwich the seal member between the first piece and the second piece. Therefore, an increase in the number of parts leads to an increase in cost and a decrease in assembly workability.

Further, in the configuration disclosed in Patent Document 1, each piece has a shape without undercut in consideration of die cutting so that each piece can be molded by die casting. Along with this, the cross-sectional shape of the scroll chamber is significantly different from the circular shape, which causes a decrease in the compression efficiency of the supply air.

Further, as a method of forming the refrigerant flow path in the housing for the turbocharger, gravity casting using a sand core can be considered. According to this method, the degree of freedom in shape is high, and it is possible to deal with complicated shapes. However, in this method, the casting cycle is long, and sand removal work and sand residue inspection work for removing sand cores are required, so that the manufacturing man-hours increase and the productivity decreases. Further, there is a possibility that the refrigerant flow path communicates with the outside due to the cavity defect and the refrigerant leaks to the outside.

The present invention has been made in view of this background, and an object of the present invention is to provide a turbocharger housing that prevents deposits from adhering, has good assembly workability, and can be easily molded by die casting.

One embodiment of the present invention is a turbocharger housing in which a compressor impeller is housed.
A shroud portion that surrounds the compressor impeller in the circumferential direction and has a shroud surface facing the compressor impeller.
A diffuser portion formed in the circumferential direction on the outer peripheral side of the compressor impeller and forming a diffuser passage through which the compressed air discharged from the compressor impeller passes.
A scroll chamber forming portion that forms a scroll chamber that guides compressed air that has passed through the diffuser passage to the outside,
A refrigerant flow path that is formed in the circumferential direction along the diffuser portion and allows a refrigerant that cools the diffuser portion to flow,
Have,
The turbocharger housing has at least a part of the scroll chamber forming portion, at least a part of the scroll chamber forming portion, the diffuser portion and the shroud portion, and is inserted inside the scroll piece. It is divided into a shroud piece and
The refrigerant flow path is composed of an annular space portion formed by a first flow path forming portion and a second flow path forming portion formed on opposite portions of the scroll piece and the shroud piece, respectively.
On the outermost peripheral portion on the inner surface of the refrigerant flow path, a contact portion formed by contacting the first flow path forming portion and the second flow path forming portion with each other is located.
The contact portion is formed with a groove portion in which the inner side surface of the refrigerant flow path is recessed outward in the radial direction and is continuous in the circumferential direction.
The groove portion is in a turbocharger housing in which a sealing material for sealing the contact portion is filled.

According to the above-mentioned one form of the turbocharger housing, the turbocharger housing is formed separately, and the refrigerant flow path is formed with the first flow path forming portion formed at the opposite portions of the scroll piece and the shroud piece, respectively. It is formed by a second flow path forming portion. At the outermost peripheral portion on the inner surface of the refrigerant flow path, a contact portion formed by contacting the first flow path forming portion and the second flow path forming portion with each other is located, and the contact portion is located with the refrigerant flow. The inner side surface of the road is recessed outward in the radial direction, and a groove portion continuous in the circumferential direction is formed. Then, the groove portion is filled with a sealing material for sealing the contact portion. As a result, it is possible to seal between the first flow path forming portion and the second flow path forming portion forming the flow path simply by filling the groove portion with the sealing material. Therefore, the first flow path forming portion and the second flow path forming portion can be sealed. There is no need to insert an O-ring between the forming portion and the assembly workability is good. Moreover, since the O-ring is not required, the number of parts can be reduced.

Further, the turbocharger housing is divided and has a scroll piece and a shroud piece, and the scroll chamber is formed by assembling at least both pieces to each other. As a result, the cross-sectional shape of the scroll chamber can be made circular, and the scroll chamber forming portion can be made into a shape without undercut that can be die-cut. As a result, the compression efficiency of the air supply can be improved, and it can be easily molded by die casting.

FIG. 3 is a cross-sectional view of a turbocharger housing according to a first embodiment. FIG. 1 is a cross-sectional view taken along the line II-II. Partial enlarged view of the cross-sectional view of the housing for the turbocharger in the first embodiment. The flow chart which shows the manufacturing method of the housing for turbocharger in Example 1. FIG. The conceptual diagram for demonstrating the manufacturing method of the housing for turbocharger in Example 1. FIG. Another conceptual diagram for explaining a method of manufacturing a housing for a turbocharger in the first embodiment. Yet another conceptual diagram for explaining the method of manufacturing the housing for the turbocharger in the first embodiment.

In the present specification, the "circumferential direction" is the rotation direction of the compressor impeller, the "axial direction" is the direction of the rotation axis of the compressor impeller, and the "diameter direction" is the radius of the virtual circle centered on the rotation axis of the compressor impeller. The radial outer direction is the direction of a straight line extending from the center of the virtual circle toward the circumference.

It is preferable that the groove portion is formed so that a virtual circle centered on the axis of the compressor impeller is located inside the groove portion. In this case, it becomes easy to uniformly fill the groove with the sealing material by utilizing the centrifugal force generated by rotating the compressor impeller around the axis, and the assembling workability is further improved.

The groove portion is V outward in the radial direction so that the deepest position is the boundary position between the first flow path forming portion and the second flow path forming portion in the cross section including the axis of the compressor impeller. It is preferable that the shape is notched in a character shape. In this case, the sealing material filled in the groove portion is easily held in the groove portion, and at the contact portion, it is easy to enter between the first flow path forming portion and the second flow path forming portion. The sealing property between the flow path forming portion and the second flow path forming portion can be further improved.

In the contact portion, it is preferable that a sealing material for sealing between the scroll piece and the shroud piece is interposed between the scroll piece and the shroud piece. In this case, the sealing property between the scroll piece and the shroud piece at the contact portion can be further improved.

In the contact portion, it is preferable that both the contact surface of the scroll piece and the contact surface of the shroud piece are parallel to the surface perpendicular to the axial direction. In this case, the centrifugal force generated by rotating the compressor impeller around the axis is used to apply the sealing material filled in the groove to the first flow path forming portion and the second flow path forming portion at the contact portion. It becomes easy to enter between, and the sealing property between the first flow path forming portion and the second flow path forming portion can be further improved.

The method for manufacturing the housing for the turbocharger is a preparatory step for preparing the scroll piece and the shroud piece, and the shroud piece is press-fitted into the scroll piece and assembled to form the first flow path forming portion and the second flow path forming portion. An assembling step of forming the refrigerant flow path composed of an annular space portion by abutting the flow path forming portion, and after the assembling step, a fluid sealing material is injected into the refrigerant flow path, or Prior to the assembling step, at least one of the first flow path forming portion and the second flow path forming portion is coated with a fluid sealing material to apply the sealing material, and the above-mentioned assembly is performed with each other. A filling step of rotating the scroll piece and the shroud piece about the axis of the compressor impeller to fill the groove with the sealing material, and a curing step of curing the sealing material filled in the groove. It is preferable to use a method for manufacturing a housing for a turbocharger including. In this case, the sealing material can be easily filled in the groove in the filling step.

The filling step is preferably performed together with the lathe processing for forming the shroud surface. In this case, since the shroud surface can be formed and the sealing material can be filled in the groove, the manufacturing process can be simplified.

(Example 1)
Hereinafter, examples of the turbocharger housing will be described.
As shown in FIG. 1, the turbocharger housing 1 accommodates a compressor impeller 13, and includes an intake port 11, a shroud portion 20, a diffuser portion 30, a scroll chamber forming portion 120, and a refrigerant flow path 5.
The shroud portion 20 has a shroud surface 22 that surrounds the compressor impeller 13 in the circumferential direction and faces the compressor impeller 13.
The diffuser portion 30 is formed on the outer peripheral side of the compressor impeller 13 in the circumferential direction, and forms a diffuser passage 15 through which the compressed air discharged from the compressor impeller 13 passes.
The scroll chamber forming unit 120 forms a scroll chamber 12 that guides the compressed air that has passed through the diffuser passage 15 to the outside.
The refrigerant flow path 5 is formed in the circumferential direction along the diffuser portion 30, and also allows the refrigerant that cools the diffuser portion 30 to flow.
The turbocharger housing 1 has a scroll piece 2 having at least a part of the scroll chamber forming portion 120, at least a part of the scroll chamber forming portion 120, a diffuser portion 30 and a shroud portion 20, and is inside the scroll piece 2. It is divided into a shroud piece 3 inserted into and a shroud piece 3.
The refrigerant flow path 5 is formed from an annular space portion 50 partitioned by a first flow path forming portion 51 and a second flow path forming portion 52 formed on facing portions of the scroll piece 2 and the shroud piece 3, respectively. Become.
On the outermost peripheral portion of the inner surface 54 of the refrigerant flow path 5, a contact portion 53 in which the first flow path forming portion and the second flow path forming portion are in contact with each other is located.
The contact portion 53 is formed with a groove portion 55 in which the inner side surface 54 of the refrigerant flow path 5 is recessed outward in the radial direction and is continuous in the circumferential direction.
Then, as shown in FIG. 3, the groove portion 55 is filled with a sealing material 56 that seals the contact portion 53.

Hereinafter, the turbocharger housing 1 of this example will be described in detail.
As shown in FIG. 1, the turbocharger housing 1 is formed by assembling a scroll piece 2, a shroud piece 3, and an outer peripheral piece 4 formed as separate members from each other in the axial direction Y.

As shown in FIGS. 1 and 2, the scroll piece 2 has an intake port 11, a first scroll chamber forming portion 121, an outer peripheral portion 125, and a first flow path forming portion 51. The intake port 11 is formed by an intake port forming portion 110 which has a tubular shape and is formed through the axial direction Y. The first scroll chamber forming unit 121 constitutes the wall surface of the intake side Y1 in the scroll chamber 12. The outer peripheral portion 125 is a portion of the first scroll chamber forming portion 121 on the side opposite to the intake side Y1 and forms the outer peripheral portion of the turbocharger housing 1. An outer peripheral piece 4 is attached to the outer peripheral portion 125. The outer peripheral piece 4 has an annular shape, and has an outer peripheral piece insertion portion 41 press-fitted into the outer peripheral portion 125 and a third scroll chamber forming portion 123 forming a wall surface on the outer peripheral side of the scroll chamber 12.

Then, as shown in FIG. 1, the first flow path forming portion 51 in the scroll piece 2 is configured to form the refrigerant flow path 5 together with the second flow path forming portion 52 described later, and is configured to form the intake port forming portion. It is provided on the Y2 side of 110. As shown in FIG. 3, the first flow path forming portion 51 has a first wall surface 511 which is a wall surface of the intake side Y1 in the refrigerant flow path 5. In this example, the first wall surface 511 is an inclined surface toward the intake side Y1 and the opposite side Y2 as it advances radially outward. The first flow path forming portion 51 has a first contact surface 531 which is a wall surface parallel to the radial direction at an end portion on the outer side in the radial direction of the first wall surface 511. The first contact surface 531 is in contact with the second contact surface 532 of the shroud piece 3 described later. The first flow path forming portion 51 is formed with a through hole 513 penetrating from the first wall surface 511 to the surface opposite to the first wall surface 511. Although not shown, two through holes 513 are formed.

As shown in FIG. 1, the shroud piece 3 has a shroud press-fitting portion 31, a second scroll chamber forming portion 122, a shroud portion 20, a diffuser portion 30, and a second flow path forming portion 52. The shroud press-fitting portion 31 is formed in a tubular shape and is press-fitted into the intake port 11. The second scroll chamber forming portion 122 forms a wall surface on the inner peripheral side of the scroll chamber 12. The shroud portion 20 forms a shroud surface 22 facing the compressor impeller 13. The diffuser portion 30 forms a diffuser surface 34 extending from the shroud surface 22 toward the scroll chamber 12. The diffuser surface 34 faces the facing surface formed on the seal plate of the bearing housing (not shown) at a predetermined distance, and the space between the facing surface and the diffuser surface 34 is the diffuser passage 15.

Then, as shown in FIG. 1, the second flow path forming portion 52 is configured to form the refrigerant flow path 5 together with the first flow path forming portion 51 described above, and is located outside the shroud portion 20 in the radial direction. It is provided on the intake port side Y1 of the diffuser portion 30. As shown in FIG. 3, the second flow path forming portion 52 has a second wall surface 521 which is a wall surface on the Y2 side of the refrigerant flow path 5. In this example, the second wall surface 521 is formed in a concave shape recessed on the Y2 side, has a U shape in a cross section parallel to the axial direction, and has a diameter of the shroud surface 22 as shown in FIG. An annular recess extending in the circumferential direction is formed on the outer side of the direction. As shown in FIG. 1, the second flow path forming portion 52 has a second contact surface 532, which is a wall surface parallel to the radial direction, at an end portion on the outer side in the radial direction of the second wall surface 521. The second contact surface 532 is in contact with the first contact surface 531 of the scroll piece 2.

As shown in FIG. 1, when the shroud press-fitting portion 31 is press-fitted into the intake port 11, the outer peripheral surface 311 of the shroud press-fitting portion 31 and the inner peripheral surface 112 of the intake port 11 are in contact with each other without a gap, and the second The contact surface 532 abuts on the first contact surface 531. As a result, the first contact surface 531 and the second contact surface 532 are brought into contact with each other to form the contact portion 53, and between the first flow path forming portion 51 and the second flow path forming portion 52. A refrigerant flow path 5 which is an annular space is formed. Then, the first wall surface 511 of the first flow path forming portion 51 and the second wall surface 521 of the second flow path forming portion 52 form the inner side surface 54 of the refrigerant flow path 5, and as shown in FIG. 3, the refrigerant The contact portion 53 is located on the outermost peripheral portion of the inner side surface 54 of the flow path 5.

As shown in FIG. 1, a groove 55 is formed in the contact portion 53. The groove portion 55 has an inner side surface 54 of the refrigerant flow path 5 recessed outward in the radial direction and continuously forms an annular shape in the circumferential direction. The groove portion 55 has a V-shaped shape, that is, a wedge-shaped cutout in a cross section parallel to the axial direction toward the outside in the radial direction. The deepest position 551 of the groove portion 55 is the boundary position between the first flow path forming portion 51 and the second flow path forming portion 52. As shown in FIGS. 2 and 3, a virtual circle 16 centered on the axis 13a of the compressor impeller 13 is located inside the groove 55.

In this example, the groove 55 is cut out in a V shape outward in the radial direction in a cross section parallel to the axial direction, but instead of this, the groove portion 55 is formed in a radial direction in a cross section parallel to the axial direction. The shape may be cut out in a U shape, an arc shape, or the like toward the outside. Also in this case, it is preferable that the deepest position 551 of the groove portion 55 is the boundary position between the first flow path forming portion 51 and the second flow path forming portion 52. Further, in this example, both the first flow path forming portion 51 and the second flow path forming portion 52 are cut out to form the groove portion 55, but the present invention is not limited to this, and only one of them is cut out to form the groove portion 55. It may be formed.

The groove portion 55 is filled with a sealing material 56. The type of the sealing material 56 is not particularly limited, but a material having a quick-drying property is preferable. For example, a sealing material used as a liquid gasket can be used. In this example, the sealing material 56 also penetrates between the first contact surface 531 and the second contact surface 532.

In this example, as shown in FIG. 3, the first contact surface 531 and the second contact surface 532, which are the boundaries between the first flow path forming portion 51 and the second flow path forming portion 52 in the contact portion 53, are It is parallel to the plane perpendicular to the axial direction. Then, on the radial outer side of the contact portion 53, the scroll piece 2 is formed with a step portion 57 protruding in the Y2 direction, and the shroud piece 3 is cut out along the outer shape of the step portion 57. The facing portion 58 is formed. The first contact surface 531 and the second contact surface 532 are in contact with each other, but the step portion 57 and the step facing portion 58 are not in contact with each other.

Next, a method of manufacturing the turbocharger housing 1 of this example will be described.
As shown in FIG. 4, the method for manufacturing the housing 1 for a turbocharger includes a preparation step S1, an assembly step S2, an application step S3, a filling step S4, and a curing step S5.

First, in the preparation step S1, the scroll piece 2, the shroud piece 3, and the outer peripheral piece 4 are prepared. The scroll piece 2, the shroud piece 3, and the outer peripheral piece 4 are individually die-cast. As shown in FIG. 5, when the shroud piece 3 is produced, first, the shroud piece precursor 3a, which is a rough material of the shroud piece 3, is die-cast. In the shroud piece precursor 3a, the shroud surface 22 and the inner side surface 312 of the shroud press-fitting portion 31 are not formed, and the inner side surface 22a of the shroud piece precursor 3a is cylindrical. Except for this, it has the outer shape of the shroud piece 3 of the shroud piece precursor 3a.

Next, the assembling step S2, as shown by an arrow P in FIG. 5, the shroud press-fit portion 31 of the shroud piece precursors 3a, by press-fitting to the inside of the inlet forming portion 110 of the scroll piece 2, FIG. 6 As shown in the above, the second contact surface 532 of the shroud piece precursor 3a is abutted against the first contact surface 531 of the scroll piece 2. As a result, the refrigerant flow path 5 formed of an annular space is formed between the first flow path forming portion 51 and the second flow path forming portion 52. Then, the through hole 513 formed in the scroll piece 2 communicates with the refrigerant flow path 5.

After that, in the applying step S3, the sealing material 56 having fluidity is injected into the refrigerant flow path 5 from the through hole 513 to apply the sealing material 56 to the refrigerant flow path 5. In the applying step S3, the sealing material 56 is in a state of being accumulated at the bottom of the refrigerant flow path 5. The amount of the sealing material 56 to be injected is not limited, but in this example, it is the same as the volume of the groove 55.

Then, as shown in FIG. 7, in the filling step S4, rotate the Scrollable Rupisu 2 and the shroud piece precursor 3a assembled to each other about the axis 13a of the con-flop suppressor impeller 13. As a result, a centrifugal force is applied to the sealing material 56 to fill the groove portion 55 located on the outermost circumference inside the refrigerant flow path 5. The filling step S4 is carried out until substantially the entire amount of the sealing material 56 injected into the refrigerant flow path 5 is uniformly filled in the groove 55 and the sealing material 56 flowing in the refrigerant flow path 5 is substantially absent. .. In this example, the filling step S4 is performed together with lathe processing for forming the shroud surface 22 on the shroud piece precursor 3a. In the turning, in order to cut the inner surface 22a of the shroud piece precursor 3a, rotates the assembly as a Scrollable Rupisu 2 and the shroud piece precursor 3a around the axis 13a of the con-flop suppressor impeller 13 .. In this example, the filling step S4 is carried out by utilizing the rotation.

Then, in the curing step S5, the rotation is continued to maintain the state in which the sealing material 56 is filled in the groove 55 for a predetermined time. As a result, the sealing material 56 is cured while being filled in the groove portion 55. By using a quick-drying seal material 56, the seal material 56 can be cured in a state of being filled in the groove portion 55 during the lathe processing. After the sealant 56 is hardened by press-fitting the outer peripheral piece 4 to scroll piece 2, the turbocharger housing 1 is manufactured.

Then, in the turbocharger housing 1, Figure 1, by connecting the refrigerant inlet and a refrigerant discharge pipe (not shown) into the through-hole 5 13 communicating with the coolant channel 5 shown in FIG. 3, the refrigerant flow of the refrigerant through these The diffuser surface 34 can be cooled by circulating the refrigerant through the road 5.

In this example, the sealing material 56 was injected into the refrigerant flow path 5 in the applying step S3 after the assembling step S2, but instead of this, the first flow path forming portion 51 and the first flow path forming portion 51 and before the assembling step S2 The applying step S3 for applying the sealing material 56 to at least one of the second flow path forming portions 52 may be carried out. In this case, in consideration of workability in the assembling step S2 after the applying step S3, a sealing material 56 having a high viscosity is used, and as shown in FIG. 5, the first flow path forming portion 51 or the first flow path forming portion 51 or the first. It is preferable to apply the coating to the portion of the two flow path forming portion 52 that forms the groove portion 55. Further, in the applying step S3 performed before the assembling step S2, a sealing material such as FIPG may be applied to at least one of the first contact surface 531 and the second contact surface 532.

Next, the action and effect of the turbocharger housing of this example will be described in detail.
According to the turbocharger housing 1 of this example, the turbocharger housing 1 is formed separately, and the refrigerant flow path is the first flow path formed at the opposite portions of the scroll piece 2 and the shroud piece 3, respectively. It is formed by the forming portion 51 and the second flow path forming portion 52. On the outermost peripheral portion of the inner surface 54 of the refrigerant flow path 5, a contact portion 53 in which the first flow path forming portion 51 and the second flow path forming portion 52 are in contact with each other is located, and the contact portion 53 is located. The 53 has a groove portion 55 formed in which the inner side surface 54 of the refrigerant flow path 5 is recessed outward in the radial direction and is continuous in the circumferential direction. The groove portion 55 is filled with a sealing material 56 that seals the contact portion 53. As a result, the groove portion 55 can be sealed between the first flow path forming portion 51 and the second flow path forming portion 52 that form the refrigerant flow path by simply filling the groove portion 55 with the sealing material 56. Therefore, the first flow path forming portion can be sealed. It is not necessary to sandwich an O-ring between the 51 and the second flow path forming portion 52, and the assembling workability is good. Moreover, since the O-ring is not required, the number of parts can be reduced.

Further, the turbocharger housing 1 is separately formed and has a scroll piece 2 and a shroud piece 3, and the scroll chamber 12 is formed by assembling at least both pieces to each other. As a result, the scroll chamber forming portion 120 can be formed into a shape without undercut that can be die-cut while making the cross-sectional shape of the scroll chamber 12 circular. As a result, the compression efficiency of the air supply can be improved, and it can be easily molded by die casting. In this embodiment, the turbocharger housing 1, scroll piece 2, although a three-piece structure consisting of the shroud piece 3 and the outer peripheral piece 4, equally in two-piece structure consisting of scroll piece 2 and the shroud piece 3 It has the effect of.

Further, the refrigerant flow path 5 in the turbocharger housing 1 of this example is applied to the conventional turbocharger housing because it is not necessary to significantly change the basic configuration of the sucrose piece and the shroud piece in the conventional turbocharger housing. It's easier to do.

Further, in this example, the groove portion 55 is formed so that the virtual circle 16 centered on the axis 13a of the compressor impeller 13 is located inside the groove portion 55. As a result, it becomes easy to uniformly fill the groove portion 55 with the sealing material 56 by utilizing the centrifugal force generated by rotating the compressor impeller 13 around the axis 13a, and the assembling workability is further improved.

Further, in this example, the groove portion 55 has a cross section including the axis 13a of the compressor impeller 13 so that the deepest position 551 is the boundary position between the first flow path forming portion 51 and the second flow path forming portion 52. It has a V-shaped notch toward the outside in the radial direction. As a result, the sealing material 56 filled in the groove portion 55 is easily held by the groove portion 55, and the sealing material 56 is placed between the first flow path forming portion 51 and the second flow path forming portion 52 in the contact portion 53. It becomes easy to enter, and the sealing property between the first flow path forming portion 51 and the second flow path forming portion 52 can be improved.

Incidentally, the second wall 5 21 of the second flow path forming portion 52 may be inclined surface gently inclined toward the groove portion 55. In this case, in the filling step S4, the sealing material 56 easily reaches the groove 55 along the second wall 5 21.

Further, in the contact portion 53, a sealing material 56 for sealing between the scroll piece 2 and the shroud piece 3 may be interposed. In this case, the sealing property between the scroll piece 2 and the shroud piece 3 at the contact portion 53 can be further improved.

Further, in this example, in the contact portion 53, the first contact surface 531 of the scroll piece 2 and the second contact surface 532 of the shroud piece 3 are both parallel to the plane perpendicular to the axial direction. As a result, the sealing material 56 filled in the groove portion 55 is brought into the contact portion 53 with the first flow path forming portion 51 and the second flow by utilizing the centrifugal force generated by rotating the compressor impeller 13 around the axis 13a. It becomes easy to enter between the path forming portion 52, and the sealing property between the first flow path forming portion 51 and the second flow path forming portion 52 can be further improved.

Further, in this example, on the radial outside of the contact portion 53, the scroll piece 2 is formed with a step portion 57 protruding in the Y2 direction, and the shroud piece 3 is cut along the outer shape of the step portion 57. The missing step facing portion 58 is formed. As a result, in the filling step S4, the sealing material 56 that has flowed in from the deepest position 551 of the groove portion 55 between the first contact surface 531 and the second contact surface 532 is prevented from coming out into the scroll chamber 12. be able to. As a result, the sealing material 56 tends to stay between the groove portion 55, the first contact surface 531 and the second contact surface 532, and thus is between the first flow path forming portion 51 and the second flow path forming portion 52. The sealing property in the above can be further improved. In this example, the step portion 57 and the step facing portion 58 are provided one by one, but the step portion 57 has a shape having a plurality of irregularities, and the step facing portion 58 is provided along the plurality of irregularities. The shape may have irregularities. In this case, it is possible to further prevent the sealing material 56 from slipping out into the scroll chamber 12, and further improve the sealing property between the first flow path forming portion 51 and the second flow path forming portion 52. it can.

Further, in the method of manufacturing the housing for the turbocharger in this example, the preparation step S1 for preparing the scroll piece 2 and the shroud piece 3 (shroud piece precursor 3a) and the shroud piece 3 (shroud piece precursor 3a) on the scroll piece 2 assembled by press-fitting the, the first flow path forming portion 51 and the second flow path forming portion 52 is abutted against, the assembling step S 2 to form a coolant channel 5 made of the space portion of the annular, set the sealing material 56 having fluidity coolant channel 5 is injected after the urging step S 2, or at least one on the flowability of the assembling step S 2 the first flow path forming portion 51 and the second flow path forming unit 52 before S3 for applying the sealing material 56 by applying the sealing material 56, and the scroll piece 2 and the shroud piece 3 (shroud piece precursor 3a) assembled to each other are shafted around the axis 13a of the compressor impeller 13. The present invention includes a filling step S4 in which the sealing material 56 is rotated to fill the groove portion, and a curing step S5 in which the sealing material 56 filled in the groove portion 55 is cured. As a result, in the filling step S4, the sealing material 56 can be easily filled in the groove portion 55.

Further, in this example, the filling step S4 is performed together with the lathe processing for forming the shroud surface 22. As a result, the shroud surface 22 can be formed and the groove portion 55 of the sealing material 56 can be filled, so that the manufacturing process can be simplified.

The present invention is not limited to the above examples and modifications, and can be applied to various examples and modifications without departing from the gist thereof.

1 turbocharger housing 2 scroll piece 3 shroud piece 5 refrigerant channel 20 shroud 30 diffuser portion 51 first flow path forming portion 52 second flow path forming portion 53 contact portion 55 the groove 551 deepest position 56 the sealing member 120 scrolls Room forming part

Claims (7)

A turbocharger housing that houses the compressor impeller.
A shroud portion that surrounds the compressor impeller in the circumferential direction and has a shroud surface facing the compressor impeller.
A diffuser portion formed in the circumferential direction on the outer peripheral side of the compressor impeller and forming a diffuser passage through which the compressed air discharged from the compressor impeller passes.
A scroll chamber forming portion that forms a scroll chamber that guides compressed air that has passed through the diffuser passage to the outside,
A refrigerant flow path that is formed in the circumferential direction along the diffuser portion and allows a refrigerant that cools the diffuser portion to flow,
Have,
The turbocharger housing has at least a part of the scroll chamber forming portion, at least a part of the scroll chamber forming portion, the diffuser portion and the shroud portion, and is inserted inside the scroll piece. It is divided into a shroud piece and
The refrigerant flow path is composed of an annular space portion formed by a first flow path forming portion and a second flow path forming portion formed on opposite portions of the scroll piece and the shroud piece, respectively.
On the outermost peripheral portion on the inner surface of the refrigerant flow path, a contact portion formed by contacting the first flow path forming portion and the second flow path forming portion with each other is located.
The contact portion is formed with a groove portion in which the inner side surface of the refrigerant flow path is recessed outward in the radial direction and is continuous in the circumferential direction.
A turbocharger housing in which the groove portion is filled with a sealing material for sealing the contact portion. The housing for a turbocharger according to claim 1, wherein the groove portion is formed so that a virtual circle centered on the axis of the compressor impeller is located inside the groove portion. The groove portion is V outward in the radial direction so that the deepest position is the boundary position between the first flow path forming portion and the second flow path forming portion in the cross section including the axis of the compressor impeller. The housing for a turbocharger according to claim 1 or 2, which has a shape notched in a shape. The housing for a turbocharger according to any one of claims 1 to 3, wherein a sealing material for sealing between the scroll piece and the shroud piece is interposed at the contact portion. In the abutting portion, the abutting surface of the scroll piece and the abutting surface of the shroud piece are both parallel to the plane perpendicular to the axial direction, which is the direction of the rotation axis of the compressor impeller , claims 1 to 4. The housing for the turbocharger according to any one of the above. According to any one of the claims 1-5, a method for producing a turbocharger housing,
The preparatory process for preparing the scroll piece and the shroud piece,
A set in which the shroud piece is press-fitted into the scroll piece and assembled, and the first flow path forming portion and the second flow path forming portion are brought into contact with each other to form the refrigerant flow path composed of an annular space portion. With the process
After the assembly step, a fluid sealant is injected into the refrigerant flow path, or before the assembly step, at least one of the first flow path forming portion and the second flow path forming portion has fluidity. The applying process of applying the sealing material and applying the sealing material, and
A filling step in which the scroll piece and the shroud piece assembled to each other are rotated about the axis of the compressor impeller to fill the groove with the sealing material.
A curing step of curing the sealing material filled in the groove, and
How to make a housing for a turbocharger, including. The method for manufacturing a housing for a turbocharger according to claim 6, wherein the filling step is performed together with lathe processing for forming the shroud surface.

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