Bearing assembly of turbocharger

Abstract

The utility model discloses a bearing assembly of a turbocharger, which is simple in structure, stable and reliable in operation and low in assembly complexity, and comprises a shell, a first cross hole and a second cross hole, and the shell is provided with a through hole, and the first cross hole and the second cross hole intersect with the through hole; a bearing is arranged in the through hole and provided with an oil passing hole communicating with the first cross hole and a connecting hole opposite to the second cross hole. The positioning pin comprises a clearance fit section and an interference fit section arranged at the tail part of the clearance fit section; the diameter D of the interference fit section is larger than that of the clearance fit section; wherein the head portion of the clearance fit section is inserted from the tail portion of the second cross hole and enters the connecting hole to be in clearance fit with the connecting hole, and the interference fit section enters the second cross hole and is in interference fit with the second cross hole. The utility model relates to the technical field of turbochargers.

Description

Technical Field

[0001] The utility model relates to the technical field of turbochargers, and more specifically to a bearing assembly of a turbocharger. Background Art

[0002] An exhaust-driven turbocharger includes a rotating group that includes a turbine wheel and a compressor wheel connected to each other by a shaft. During operation, the shaft can be expected to rotate at speeds in excess of 200,000 rpm, depending on factors such as the size of the various turbocharger components. To ensure proper rotor dynamic performance, the rotating group should be well balanced and well supported.

[0003] In many conventional arrangements, the turbocharger shaft is rotatably supported within the intermediate housing by one or more bearings (e.g., oil-lubricated, air bearings, ball bearings, magnetic bearings, etc.). In some arrangements, the one or more bearings may be positioned in the bore of the intermediate housing by one or more locating mechanisms. For example, a locating pin may be employed as part of the locating mechanism to position the semi-floating bearing in the bore of the housing.

[0004] The bearing assembly of a conventional turbocharger (please refer to the turbocharger housing and bearing locating pin disclosed in announcement number CN103122775B, and paragraphs 0016 to 0018 of the specific implementation method of the specification) has a cross hole with a diameter larger than that of the cross hole at the bottom for the locating pin to pass through, and a cross hole with a diameter smaller than that of the locating pin for interference fit. Its structural design limits the locating pin to only one preferred assembly method, namely: inserting the tail of the locating pin through the head of the cross hole at the top of the through hole, and continuously pressing the locating pin downward with the help of a guiding tool, so that the tail end of the locating pin passes through the hole body on the bearing, enters the cross hole at the bottom of the through hole and has an interference fit with the cross hole at the bottom, and the head of the locating pin is in the hole body on the bearing. After the above assembly is completed, the bearing can be limited. However, the structural design of the bearing assembly of the conventional turbocharger is unreasonable, resulting in more stringent requirements on the processing technology, more assembly steps, and more guiding tools. Utility Model Content

[0005] In view of the shortcomings and defects of the prior art, a bearing assembly for a turbocharger is provided which has a simple structure, stable and reliable operation, and low assembly complexity.

[0006] A bearing assembly for a turbocharger, comprising:

[0007] A shell, wherein the shell is provided with a through hole and a second cross hole intersecting with the through hole;

[0008] A bearing is arranged in the through hole, and the bearing is provided with a connecting hole opposite to the second cross hole;

[0009] A locating pin, the locating pin comprising a clearance fit section disposed at a first end and an interference fit section disposed at a second end;

[0010] The diameter D of the interference fit section is greater than the diameter D of the clearance fit section, and the diameter D of the clearance fit section is smaller than the diameter D of the second cross hole;

[0011] The head of the clearance fit section is inserted from the tail of the second cross hole and enters the connecting hole to be clearance-fitted with the connecting hole, and the interference fit section enters the second cross hole and is interference-fitted with the second cross hole.

[0012] After adopting the above structure, the bearing assembly of a turbocharger of the utility model has the following advantages compared with the prior art: the diameter D of the interference fit section of the locating pin is larger than the diameter D of the clearance fit section, and the diameter D of the clearance fit section is smaller than or equal to the diameter D of the second cross hole;

[0013] When assembling the positioning pin, first insert the head of the clearance fit section from the tail of the second cross hole, and make the clearance fit end enter the connecting hole to fit with the clearance of the connecting hole. During this process, the interference fit section enters the second cross hole and has an interference fit with the second cross hole. The assembly steps of the positioning pin in the present application are simpler.

[0014] After the above assembly is completed, the locating pin is in a stable position after interference fit, and the bearing can be positioned in the through hole, ensuring that the locating pin and the bearing will not fall out during operation, so that the device has high operating reliability;

[0015] In addition, the clearance fit section and the connection hole clearance fit can ensure that during the assembly process, the clearance fit section will not cause deformation of the bearing, avoid affecting the operation of the bearing, and further improve the reliability of the device operation.

[0016] As an improvement of the present invention, the shell is further provided with a first cross hole intersecting with the through hole, the bearing is provided with an oil hole connected with the first cross hole, and the first cross hole and the second cross hole are vertically arranged along the same axis A.

[0017] As an improvement of the present invention, the diameter D of the first cross hole is smaller than or equal to the diameter D of the second cross hole.

[0018] As an improvement of the present invention, the axis A of the first cross hole and the second cross hole is perpendicular to the axis B of the through hole.

[0019] As an improvement of the present invention, an inclined surface is provided between the peripheral side of the clearance fit section and the peripheral side of the interference fit section.

[0020] As an improvement of the present invention, the diameter of the tail opening of the second cross hole is enlarged.

[0021] As an improvement of the utility model, the housing is provided with a lubricant channel, and the lubricant channel is communicated with the head of the first cross hole.

[0022] As an improvement of the utility model, the bearing is provided with an axially penetrating inner hole, and the inner hole is interconnected with the oil hole and the connecting hole.

[0023] As an improvement of the present utility model, an assembly opening is provided at the tail of the lower part of the shell corresponding to the second cross hole, and the assembly opening is for a guide tool and a locating pin to pass through. The guide tool includes a push rod, and the diameter of the upper end face of the push rod is larger than the diameter of the second cross hole. The push rod presses the locating pin upward to a preset assembly position. In the preset assembly position, the upper end face of the push rod abuts against the end face of the shell at the tail end of the second cross hole to limit the pressure of the push rod on the locating pin. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a cross-sectional structural schematic diagram of the utility model.

[0025] Figure 2 The utility model Figure 1 Enlarged schematic diagram of the structure at point C in the middle.

[0026] Figure 3 It is a schematic diagram of the cross-sectional structure of the shell of the utility model.

[0027] Figure 4 It is a schematic diagram of the bearing structure of the utility model.

[0028] Figure 5 It is a schematic diagram of the positioning pin structure of the utility model.

[0029] Figure 6 It is a schematic diagram of the assembly implementation of the utility model.

[0030] Figure 7 It is a three-dimensional structural schematic diagram of the utility model.

[0031] As shown in the figure: 1. Shell; 1.1. Through hole; 1.2. First cross hole; 1.21. Diameter D of the first cross hole; 1.3. Second cross hole; 1.31. Diameter D of the second cross hole; 1.4. Lubricant channel; 1.5. Assembly port; 2. Bearing; 2.1. Oil hole; 2.2. Connecting hole; 2.3. Inner hole; 3. Positioning pin; 3.1. Clearance fit section; 3.11. Diameter D of the clearance fit section; 3.2. Interference fit section; 3.21. Diameter D of the interference fit section; 3.3. Inclined surface; 4. Push rod. DETAILED DESCRIPTION

[0032] The utility model is further described below in conjunction with the accompanying drawings and specific embodiments.

[0033] See also Figure 1-7 As shown, a bearing assembly of a turbocharger comprises:

[0034] A housing 1, wherein the housing 1 is provided with a through hole 1.1 and a second cross hole 1.3 intersecting with the through hole 1.1;

[0035] A bearing 2 is disposed in the through hole 1.1, and the bearing 2 is provided with a connecting hole 2.2 opposite to the second cross hole 1.3;

[0036] The positioning pin 3 comprises a clearance fit section 3.1 arranged at the first end, and an interference fit section 3.2 arranged at the second end; wherein the interference fit section 3.2 is arranged at the tail end of the clearance fit section 3.1;

[0037] The diameter D3.21 of the interference fit section 3.2 is greater than the diameter D3.11 of the clearance fit section 3.1, and the diameter D3.11 of the clearance fit section 3.1 is less than or equal to the diameter D1.31 of the second cross hole 1.3;

[0038] The head of the clearance fit section 3.1 is inserted from the tail of the second cross hole 1.3 and enters the connecting hole 2.2 to have a clearance fit with the connecting hole 2.2, and the interference fit section 3.2 enters the second cross hole 1.3 to have an interference fit with the second cross hole 1.3.

[0039] The diameter D3.21 of the interference fit section 3.2 of the positioning pin 3 is larger than the diameter D3.11 of the clearance fit section 3.1, and the diameter D3.11 of the clearance fit section 3.1 is smaller than or equal to the diameter D1.31 of the second cross hole 1.3;

[0040] When assembling the positioning pin 3, firstly, the head of the clearance fitting section 3.1 is inserted from the tail of the second cross hole 1.3, and the clearance fitting end is made to enter the connecting hole 2.2 to be clearance-fitted with the connecting hole 2.2. During this process, the interference fitting section 3.2 enters the second cross hole 1.3 and is interference-fitted with the second cross hole 1.3.

[0041] After the above assembly is completed, the locating pin 3 is in a stable position after interference fit, and the bearing 2 can be positioned in the through hole 1.1, ensuring that the locating pin 3 and the bearing 2 will not fall out during operation, so that the device has high operating reliability;

[0042] In addition, the clearance fit between the clearance fit section 3.1 and the connecting hole 2.2 can ensure that during the assembly process, the clearance fit section 3.1 will not cause deformation of the bearing 2, and since the clearance fit section 3.1 will not contact the hole wall of the second cross hole 1.3 during the assembly process, no rough surface will appear due to contact. The wall surface of the clearance fit section 3.1 is smoother, and the connection effect with the bearing 2 is better, avoiding affecting the operation of the bearing 2, and further improving the reliability of the operation of the device.

[0043] See also Figure 1-7 As shown, the housing 1 is also provided with a first cross hole 1.2 intersecting with the through hole 1.1, and the bearing 2 is provided with an oil hole 2.1 connected with the first cross hole 1.2. The first cross hole 1.2 and the second cross hole 1.3 are vertically arranged along the same axis A, wherein the oil hole 2.1 is connected with the inner hole of the bearing 2.

[0044] See also Figure 1-7 As shown, the diameter D1.21 of the first cross hole 1.2 is less than or equal to the diameter D1.31 of the second cross hole 1.3. The axis A of the first cross hole 1.2 and the second cross hole 1.3 is perpendicular to the axis B of the through hole 1.1.

[0045] After the above improvements, the present invention is different from the conventional turbocharger bearing 2 assembly in that: the first cross hole 1.2 of the present invention does not need to be passed through by the positioning pin 3, so the diameters of the first cross hole 1.2 and the second cross hole 1.3 of the present invention can be the same or different. When the diameters are the same and the same axis A is set, the first cross hole 1.2 and the second cross hole 1.3 can be completed by the same processing step;

[0046] In addition, since the positioning pin 3 does not need to pass through a plurality of holes, the number of guiding tools and assembly processes required when assembling the positioning pin 3 is relatively small, and the assembly steps are more reasonable.

[0047] The bearing assembly of a conventional turbocharger (please refer to the turbocharger housing and bearing locating pin disclosed in announcement number CN103122775B, and paragraphs 0016 to 0018 of the specific implementation method of the specification) has a cross hole with a diameter larger than that of the cross hole at the bottom for the locating pin to pass through, and a cross hole with a diameter smaller than that of the locating pin for interference fit. Its structural design limits the locating pin to only one preferred assembly method, namely: inserting the tail of the locating pin through the head of the cross hole at the top of the through hole, and continuously pressing the locating pin downward with the help of a guiding tool, so that the tail end of the locating pin passes through the hole body on the bearing, enters the cross hole at the bottom of the through hole and has an interference fit with the cross hole at the bottom, and the head of the locating pin is in the hole body on the bearing. After the above assembly is completed, the bearing can be limited. However, the structural design of the bearing assembly of the conventional turbocharger is unreasonable, resulting in more stringent requirements on the processing technology, more assembly steps, and more guiding tools.

[0048] See also Figure 1 As shown, the axis A of the first cross hole 1.2 and the second cross hole 1.3 are perpendicular to the axis B of the through hole 1.1. After the above improvements, the structure is reasonably designed, easy to process, and has good rigidity.

[0049] See also Figure 5 As shown, a bevel 3.3 is provided between the circumferential side of the clearance fit section 3.1 and the circumferential side of the interference fit section 3.2. The bevel 3.3 plays a transition role between the circumferential side of the clearance fit section 3.1 and the circumferential side of the interference fit end, and plays a transition and guiding role when the locating pin 3 is assembled in the first cross hole 1.2, so that the assembly of the locating pin 3 is smoother.

[0050] See also Figure 1-2 As shown, the tail opening diameter of the second cross hole 1.3 is enlarged. After the above improvement, it is beneficial for the interference fit section 3.2 of the positioning pin 3 to smoothly enter the second cross hole 1.3.

[0051] The housing 1 is provided with a lubricant channel 1.4, which is connected to the head of the first cross hole 1.2; the bearing 2 is provided with an axially penetrating inner hole 2.3, which is connected to the oil hole 2.1 and the connecting hole 2.2. After the above improvement, the lubricant in the lubricant channel 1.4 enters the oil hole 2.1 through the first cross hole 1.2, and enters the two ends of the bearing 2 through the inner hole 2.3 of the bearing 2, which plays a role in lubricating and cooling the components at the two ends;

[0052] In addition, there are gaps at the position on the circumferential side of the bearing 2 opposite to the tail end of the first cross hole 1.2 and the position opposite to the head of the second cross hole 1.3. The lubricant entering the first cross hole 1.2 can also enter the gap, and the components in the through hole 1.1 play a role in lubrication and heat dissipation.

[0053] See also Figure 1 , Figure 6 As shown, an assembly opening 1.5 is provided at the tail of the lower part of the shell 1 corresponding to the second cross hole 1.3, and the assembly opening is for a guide tool and a positioning pin 3 to pass through, and the guide tool includes a push rod 4.

[0054] When assembling the locating pin 3, the clearance fit section 3.1 of the locating pin 3 can be inserted from the assembly opening 1.5 to the tail end of the second cross hole 1.3. Further, the upper end of the push rod 4 is inserted from the assembly opening 1.5, and the upper end of the push rod 4 is used to press the locating pin 3 to install the locating pin 3 to the preset assembly position. The length of the locating pin needs to meet the requirement that the clearance fit section 3.1 can be assembled in the connecting hole 2.2, and the interference fit section 3.2 can be assembled in the second cross hole 1.3 at the preset assembly position.

[0055] The diameter of the upper end face of the push rod 4 is larger than the diameter of the second cross hole 1.3. After the push rod 4 presses the locating pin 3 to the preset assembly position, the upper end face of the push rod 4 abuts against the end face of the shell 1 at the tail end of the second cross hole 1.3. At this time, the upper end face of the push rod 4 cannot continue to press on the locating pin 3 to avoid excessive movement of the locating pin 3.

[0056] After the above improvements, compared with the complicated press-fitting tooling and press-fitting process of the traditional turbocharger bearing assembly, the present application has the characteristics of simpler press-fitting process flow for the locating pin 3, simple press-fitting tooling structure, lower cost, and more reliable limiting method for the assembly height of the locating pin 3.

[0057] The above are only preferred implementations of the utility model. The protection scope of the utility model is not limited to the above embodiments. All technical solutions under the idea of ​​the utility model belong to the protection scope of the utility model. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the utility model should also be regarded as the protection scope of the utility model.

Claims

1. A bearing assembly for a turbocharger, characterized in that: include: A shell (1), wherein the shell (1) is provided with a through hole (1.1) and a second intersecting hole (1.3) intersecting with the through hole (1.1); A bearing (2) is arranged in the through hole (1.1), and the bearing (2) is provided with a connecting hole (2.2) opposite to the second cross hole (1.3); A positioning pin (3), the positioning pin (3) comprising a clearance fit section (3.1) arranged at a first end, and an interference fit section (3.2) arranged at a second end; The diameter D (3.21) of the interference fit section (3.2) is greater than the diameter D (3.11) of the clearance fit section (3.1), and the diameter D (3.11) of the clearance fit section (3.1) is smaller than the diameter D (1.31) of the second cross hole (1.3); The head of the clearance fit section (3.1) is inserted from the tail of the second cross hole (1.3) and enters the connecting hole (2.2) to be clearance-fitted with the connecting hole (2.2), and the interference fit section (3.2) enters the second cross hole (1.3) to be interference-fitted with the second cross hole (1.3).

2. A turbocharger bearing assembly according to claim 1, characterized in that: The housing (1) is also provided with a first cross hole (1.2) intersecting with the through hole (1.1), and the bearing (2) is provided with an oil hole (2.1) communicating with the first cross hole (1.2).

3. The bearing assembly of a turbocharger according to claim 2, characterized in that: The first cross hole (1.2) and the second cross hole (1.3) are arranged vertically along the same axis A, and the diameter D (1.21) of the first cross hole (1.2) is smaller than or equal to the diameter D (1.31) of the second cross hole (1.3).

4. The bearing assembly of a turbocharger according to claim 3, characterized in that: The axis A of the first cross hole (1.2) and the second cross hole (1.3) is perpendicular to the axis B of the through hole (1.1).

5. The bearing assembly of a turbocharger according to claim 1, characterized in that: An inclined surface (3.3) is provided between the peripheral side of the clearance fit section (3.1) and the peripheral side of the interference fit section (3.2).

6. The bearing assembly of a turbocharger according to claim 1, characterized in that: The tail opening diameter of the second cross hole (1.3) is enlarged.

7. The bearing assembly of a turbocharger according to claim 1, characterized in that: The housing (1) is provided with a lubricant channel (1.4), and the lubricant channel (1.4) is connected to the head of the first cross hole (1.2).

8. The bearing assembly of a turbocharger according to claim 1, characterized in that: The bearing (2) is provided with an inner hole (2.3) that penetrates axially, and the inner hole (2.3) is interconnected with the oil hole (2.1) and the connecting hole (2.2).

9. The bearing assembly of a turbocharger according to claim 1, characterized in that: An assembly opening (1.5) is provided at the tail of the second cross hole (1.3) at the lower part of the shell (1), and the assembly opening (1.5) is for a guide tool and a positioning pin (3) to pass through. The guide tool comprises a push rod (4), and the diameter of the upper end surface of the push rod (4) is larger than the diameter of the second cross hole (1.3). The push rod (4) presses the positioning pin (3) upward to a preset assembly position. At the preset assembly position, the upper end surface of the push rod (4) abuts against the end surface of the shell (1) at the tail end of the second cross hole (1.3), so as to limit the pressing of the push rod (4) on the positioning pin (3).

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