Air compressor main shaft assembling method and air compressor

Abstract

The invention provides an air compressor main shaft assembling method which comprises the steps that a rotor main shaft and a pressing piece are machined, components are assembled, and a rotor magnet sheath is assembled, and the rotor main shaft is integrally machined and formed and does not need to be assembled. The first bearing sleeve, the rotor magnet and the second bearing sleeve respectively sleeve the rotor main shaft in a penetrating manner, so that the coaxiality requirement of the first bearing sleeve, the rotor magnet and the second bearing sleeve is met, the overall rigidity of the rotor shaft is increased, and the stability of the rotor shaft at a high rotating speed is improved. The first bearing sleeve and the second bearing sleeve are both in interference fit with the rotor main shaft, and the rotor magnet sheath is in interference fit with the rotor magnet. The interference fit assembling mode enables the assembling process to be simple, operation is convenient, the assembling requirement can be lowered, and the assembling time can be shortened. The invention further discloses the air compressor.

Description

Technical Field

[0001] The present application relates to the technical field of air compressors, and in particular to an air compressor main shaft assembly method and an air compressor. Background Art

[0002] The air compressor for hydrogen fuel cells is one of the important components in the hydrogen fuel cell system. It raises the oxygen in the ambient atmosphere to a certain pressure, transports it to the hydrogen fuel cell reactor, and undergoes an electrochemical reaction with hydrogen to produce electricity and water. The driving energy of the air compressor comes from the hydrogen fuel cell reactor. The air compressor and the hydrogen fuel cell reactor form a mutually dependent relationship, so the working characteristics of the air compressor have a great influence on the hydrogen fuel cell.

[0003] The rotor shaft is the shaft that transmits the rotational motion and torque of the motor to the downstream components. At present, the air compressor rotor shafts commonly used in the market mostly adopt a hollow segmented structure. The hollow rotor shaft is usually manufactured as follows: first, by extruding a cylindrical billet or a tube billet, drilling or processing it into a hollow, and then placing a magnet in the hollow shaft segment, and then connecting the hollow shaft segment with openings on both sides to the shaft segments at both ends by press fitting or welding. This manufacturing and assembly method is complex and difficult to process.

[0004] The expander uses turbine expansion to do work in the fuel cell system, recovering part of the energy in the exhaust gas of the fuel cell stack, thereby reducing the air compressor's demand for the stack power and improving the efficiency of the fuel cell stack. The fuel cell stack will produce water vapor during the reaction process, which may condense into liquid water in the expander, affecting system performance and safety. Summary of the invention

[0005] The purpose of the present application is to provide a method for assembling a hollow machine main shaft to reduce the difficulty of machining and assembling a rotor shaft assembly and improve the performance of an air compressor; the present application also provides an air compressor.

[0006] In order to solve the above technical problems, the present application provides an air compressor main shaft assembly method, comprising the steps of:

[0007] Processing a rotor main shaft, wherein the rotor main shaft is processed and formed in one piece;

[0008] Processing a pressing piece, wherein the supporting end of the pressing piece is processed with a drainage slope arranged obliquely from the outer circumference to the end;

[0009] Assembling the components, sequentially inserting the first bearing sleeve, the rotor magnet, and the second bearing sleeve onto the rotor main shaft, wherein both the first bearing sleeve and the second bearing sleeve are interference fit with the rotor main shaft, and a semi-finished rotor shaft component is obtained;

[0010] The rotor magnet sheath is assembled, and the rotor magnet sheath is assembled on the outside of the rotor magnet, and the rotor magnet sheath is interference fit with the rotor magnet.

[0011] Optionally, an axial positioning member is provided on the rotor main shaft, and a side of the first bearing sleeve facing away from the rotor magnet is positioned by the axial positioning member.

[0012] Optionally, a first step ring is provided on one end of the first bearing sleeve close to the rotor magnet, a second step ring is provided on one end of the second bearing sleeve close to the rotor magnet, and the rotor magnet sleeve is interference connected to the first step ring, the rotor magnet and the second step ring.

[0013] Optionally, the component assembling step specifically includes:

[0014] Assemble the components, and sequentially sleeve the first bearing sleeve, the rotor magnet, and the second bearing sleeve on the rotor main shaft, and position the first bearing sleeve on the axial positioning member;

[0015] The assembly is compressed, and a compression piece is assembled on the rotor main shaft to compress the side of the second bearing sleeve facing away from the rotor magnet.

[0016] Optionally, the component assembly step includes:

[0017] Heating the first bearing sleeve to a first preset temperature;

[0018] Assembling the heated first bearing sleeve, and assembling the heated first bearing sleeve on the rotor main shaft so that the first bearing sleeve fits the axial positioning member;

[0019] Assembling the rotor magnet, and assembling the rotor magnet on the rotor main shaft so that the first end of the rotor magnet abuts against the first step ring;

[0020] heating the second bearing sleeve to a second preset temperature;

[0021] Assemble the heated second bearing sleeve, and assemble the heated second bearing sleeve on the rotor main shaft so that the second step ring abuts against the second end of the rotor magnet.

[0022] Optionally, the first preset temperature is T1, and T1 satisfies the following formula:

[0023] T1=(d1-D1) / (a1×D1)+T0

[0024] Wherein, D1 is the inner hole diameter of the first bearing sleeve, d1 is the diameter of the matching shaft section between the rotor main shaft and the inner hole of the first bearing sleeve, a1 is the material linear expansion coefficient of the first bearing sleeve, and T0 is the room temperature.

[0025] Optionally, the second preset temperature is T2, and T2 satisfies the following formula:

[0026] T2=(d2-D2) / (a2×D2)+T0

[0027] Wherein, D2 is the inner hole diameter of the second bearing sleeve, d2 is the diameter of the matching shaft section between the rotor main shaft and the inner hole of the second bearing sleeve, a2 is the material linear expansion coefficient of the second bearing sleeve, and T0 is the room temperature.

[0028] Optionally, the component pressing step includes:

[0029] After the heated second bearing sleeve is assembled, the pressing piece is tightened once, with a tightening torque of 10Nm-20Nm;

[0030] Secondary tightening: After the second bearing sleeve cools to room temperature, the clamping piece is tightened for the second time with a tightening torque of 25Nm-50Nm.

[0031] Optionally, after the assembly pressing step, the step of:

[0032] Cutting is performed on the outer surfaces of the first bearing sleeve, the rotor magnet, and the second bearing sleeve that are in contact with the rotor magnet sleeve.

[0033] Optionally, the rotor magnet sheath assembly steps include:

[0034] heating the rotor magnet sheath;

[0035] Assemble the heated rotor magnet sleeve, position the semi-finished rotor shaft assembly in a positioning tool, the positioning tool has a mounting through hole, the mounting through hole includes a first hole segment and a second hole segment, a positioning step is formed between the first hole segment and the second hole segment, insert the semi-finished rotor shaft assembly into the mounting through hole, the first step ring abuts against the positioning step, the rotor magnet is located in the first hole segment, and the gap between the rotor magnet and the first hole segment is not less than the thickness of the rotor magnet sleeve, and the heated rotor magnet sleeve is fitted into the gap until it abuts against the positioning step.

[0036] An air compressor, characterized by comprising:

[0037] A housing, wherein a rotor shaft assembly assembled by the air compressor main shaft assembly method as described in any one of the above items is disposed in the housing;

[0038] A pressure end, arranged at one end of the shell, for providing compressed air for the fuel cell, wherein the pressure end is provided with a pressure wheel, and the pressure wheel is fixed to one end of the rotor shaft assembly close to the pressure end;

[0039] A turbine end is arranged at the other end of the shell and is used to recover the exhaust gas generated by the fuel cell reaction. The turbine end is provided with a turbine, and the turbine is fixed to one end of the rotor shaft assembly close to the turbine end;

[0040] The rotor shaft assembly is in abutment with the turbine, and the abutment ends of the rotor shaft assembly and the turbine form a groove which is concavely arranged in the radial direction.

[0041] In this embodiment, the back side of the turbine is a guide slope that surrounds the groove, the guide slope and the drainage slope are connected at the root, and the groove is a water-throwing trough surrounded by the guide slope and the drainage slope.

[0042] In this embodiment, a support step protruding from the back side of the turbine is provided at the hub position of the turbine, and the guide slope is composed of the outer periphery of the support step and the back end face of the turbine.

[0043] In this embodiment, the supporting step and the pressing member are in abutment with each other, and the groove is arranged at the abutment end of the supporting step and the pressing member.

[0044] The present application provides an air compressor main shaft assembly method, comprising the steps of: processing a rotor main shaft and a clamping piece, assembly of components and assembly of a rotor magnet sleeve, wherein the rotor main shaft is formed as an integral piece and does not require assembly, and the clamping piece is processed with a drainage ramp. The first bearing sleeve, the rotor magnet, and the second bearing sleeve are respectively sleeved on the rotor main shaft, which meets the coaxiality requirements of the first bearing sleeve, the rotor magnet, and the second bearing sleeve, increases the overall stiffness of the rotor shaft, and improves the stability of the rotor shaft at high speeds. The first bearing sleeve and the second bearing sleeve are both interference fit with the rotor main shaft, and the rotor magnet sleeve is interference fit with the rotor magnet. The interference fit assembly method makes the assembly process simple and easy to operate, which can reduce assembly requirements and shorten assembly time.

[0045] The present application provides an air compressor, including a housing, a compression end and a turbine end. The exhaust gas generated by the fuel cell enters from the turbine end, drives the turbine to rotate, the turbine drives the rotor shaft assembly to rotate, the rotor shaft assembly drives the pressure wheel to rotate, thereby compressing air and providing it to the fuel cell. The compression piece and the turbine form a groove, and the cooling water is thrown out by centrifugal force through the rotation of the rotor, reducing the risk of condensed water entering the motor and improving the performance of the air compressor. The air compressor provided by the present application can utilize the energy of the exhaust gas, reduce energy waste, and improve the efficiency of the fuel cell stack. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 A schematic diagram of the structure of the rotor main shaft disclosed in the embodiment of the present application;

[0047] Figure 2 This is a schematic structural diagram of a semi-finished rotor shaft assembly disclosed in an embodiment of the present application;

[0048] Figure 3 A schematic diagram of the structure of the rotor shaft assembly disclosed in the embodiment of the present application;

[0049] Figure 4 This is a schematic diagram of the structure of the positioning tool disclosed in the embodiment of the present application;

[0050] Figure 5 This is a schematic diagram of assembling the rotor magnet sheath disclosed in the embodiment of the present application;

[0051] Figure 6 It is a schematic structural diagram of a first bearing sleeve disclosed in an embodiment of the present application;

[0052] Figure 7 A schematic diagram of the structure of a second bearing sleeve disclosed in an embodiment of the present application;

[0053] Figure 8 This is a flow chart of the air compressor main shaft assembly method disclosed in the embodiment of the present application;

[0054] Fig. 9 This is a schematic diagram of the air compressor structure disclosed in the embodiment of the present application;

[0055] Fig.10 This is a schematic diagram of the water trough structure disclosed in the embodiment of the present application.

[0056] Figure 1-Figure 10 The meanings of the reference numerals in the figure are as follows:

[0057] 101 is the rotor main shaft, 102 is the axial positioning member, 103 is the first bearing sleeve, 104 is the rotor magnet, 105 is the second bearing sleeve, 106 is the pressing member, 1061 is the water-throwing groove, 107 is the rotor magnet sleeve, 108 is the positioning tool, 1081 is the positioning step, 109 is the turbine, and 1091 is the turbine water-throwing groove;

[0058] 901 is a shell, 902 is a pressure wheel, 903 is a rotor shaft assembly, 904 is a groove, 1091 is a drainage slope, 1061 is a drainage slope, and 1092 is a supporting step. DETAILED DESCRIPTION

[0059] In order to enable those skilled in the art to better understand the technical solution of the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0060] Please refer to Figure 3 As shown, the rotor shaft assembly processed in the present application includes a rotor main shaft 101, a first bearing sleeve 103, a rotor magnet 104, a second bearing sleeve 105 and a rotor magnet sleeve 107. The specific structure of the rotor main shaft 101 is as follows: Figure 1 As shown, the rotor main shaft 101 is an integrated structure, which is integrally processed and formed without assembly. The first bearing sleeve 103 and the second bearing sleeve 105 are used to connect the bearings supporting the rotor shaft.

[0061] like Figure 8 As shown, this embodiment discloses a method for assembling a main shaft of an air compressor, comprising:

[0062] Step S10, processing the rotor main shaft;

[0063] The rotor main shaft 101 can be processed by using a bar material, or by using other materials. The specific structure of the rotor main shaft 101 is as follows: Figure 1 As shown, it is an integrated process and does not require assembly.

[0064] The pressing piece 106 is processed in the machining stage. During the construction process S10 , the drainage slope 1061 can be cut on the pressing piece 106 , or an independent processing step can be set for the pressing piece 106 to provide a pre-processed pressing piece 106 with the drainage slope 1061 .

[0065] Step S20, component assembly;

[0066] The first bearing sleeve 103, the rotor magnet 104 and the second bearing sleeve 105 are sequentially inserted into the rotor main shaft 101, and the first bearing sleeve 103, the rotor magnet 104 and the second bearing sleeve 105 are coaxially arranged to meet the coaxiality requirements of the three. The rotor magnet 104 is a cylindrical magnet. In order to reduce the difficulty of assembly, the first bearing sleeve 103, the second bearing sleeve 105 and the rotor main shaft 101 are all installed in an interference fit manner to avoid relative rotation between the first bearing sleeve 103, the second bearing sleeve 105 and the rotor main shaft 101. In order to avoid damaging the rotor magnet 104, the rotor magnet 104 and the rotor main shaft 101 are clearance-fitted. After the components are assembled, a semi-finished rotor shaft component is obtained, such as Figure 2 It should be noted that the first bearing sleeve 103, the second bearing sleeve 105 and the rotor magnet sleeve 107 are all made of non-magnetic metal.

[0067] For the convenience of explanation, the shaft section where the rotor main shaft 101 cooperates with the first bearing sleeve 103 is defined as the first shaft section, the shaft section where the rotor main shaft 101 cooperates with the rotor magnet 104 is defined as the second shaft section, and the shaft section where the rotor main shaft 101 cooperates with the second bearing sleeve 105 is defined as the third shaft section. In order to facilitate the assembly of the first bearing sleeve 103, the outer diameters of the second shaft section and the third shaft section are both smaller than the outer diameter of the first shaft section. The outer diameters of the second shaft section and the third shaft section can be the same, or the outer diameter of the second shaft section can be set to be larger than the outer diameter of the third shaft section, so as to facilitate the insertion of the rotor magnet 104.

[0068] Step S30, assembling the rotor magnet sheath;

[0069] In order to protect the rotor magnet 104 to a certain extent, the rotor magnet sheath 107 is assembled on the outside of the rotor magnet 104 . In order to prevent the rotor magnet sheath 107 from rotating relative to the rotor magnet 104 , the rotor magnet sheath 107 and the rotor magnet 104 are interference fit.

[0070] In the air compressor main shaft assembly method disclosed in this embodiment, the first bearing sleeve 103 and the second bearing sleeve 105 are both interference fit with the rotor main shaft 101, the rotor magnet 104 is clearance fit with the rotor main shaft 101, and the rotor magnet sleeve 107 is interference fit with the rotor magnet 104. The assembly process is simple and easy to operate, which can reduce assembly requirements and shorten assembly time.

[0071] like Figure 1 As shown, in a specific embodiment of the present application, an axial positioning member 102 is provided on the rotor main shaft 101, and the side of the first bearing sleeve 103 facing away from the rotor magnet 104 is positioned by the axial positioning member 102. The axial positioning member 102 can be a positioning collar or other types.

[0072] A first step ring is provided on one end of the first bearing sleeve 103 close to the rotor magnet 104, a second step ring is provided on one end of the second bearing sleeve 105 close to the rotor magnet 104, and the rotor magnet sleeve 107 is interference-connected to the first step ring, the rotor magnet 104, and the second step ring. In order to facilitate the assembly of the rotor magnet sleeve 107, the first step ring, the rotor magnet 104, and the second step ring have the same outer diameter.

[0073] In a specific embodiment of the present application, the component assembly step includes:

[0074] Step S21, component assembly;

[0075] The first bearing sleeve 103 , the rotor magnet 104 and the second bearing sleeve 105 are sequentially inserted on the rotor main shaft 101 , and the first bearing sleeve 103 is positioned on the axial positioning member 102 to prevent the first bearing sleeve 103 from axial displacement.

[0076] Step S22, pressing the components;

[0077] In order to ensure the stability of the semi-finished rotor shaft assembly after assembly, the clamping member 106 is assembled on the rotor main shaft 101 after the assembly assembly step, so as to clamp the side of the second bearing sleeve 105 facing away from the rotor magnet 104. Specifically, the clamping member 106 can be a clamping nut, and the rotor main shaft 101 is provided with a thread matching the clamping nut.

[0078] In a specific embodiment of the present application, the component assembly step includes:

[0079] Step S211, heating the first bearing sleeve;

[0080] In order to improve the stability of the rotor shaft structure, an interference fit is adopted between the first bearing sleeve 103 and the rotor main shaft 101. In order to facilitate the installation of the first bearing sleeve 103, the first bearing sleeve 103 is first heated. The first bearing sleeve 103 can be heated by a heating furnace, specifically, heated to a first preset temperature.

[0081] Step S212, assembling the heated first bearing sleeve;

[0082] The heated first bearing sleeve 103 is assembled onto the rotor main shaft 101 , so that the first bearing sleeve 103 fits the axial positioning member 102 .

[0083] Step S213, assembling rotor magnets;

[0084] The rotor magnet 104 is assembled on the rotor main shaft 101 so that the first end of the rotor magnet 104 abuts against the first step ring.

[0085] Step S214, heating the second bearing sleeve;

[0086] In order to facilitate the interference connection between the second bearing sleeve 105 and the rotor main shaft 101, the second bearing sleeve 105 may be heated by a heating furnace to a second preset temperature.

[0087] Step S215, assembling the heated second bearing sleeve;

[0088] The second bearing sleeve 105 heated to a second preset temperature is assembled on the rotor main shaft 101 , so that the second step ring abuts against the second end of the rotor magnet 104 .

[0089] It should be noted that step S211 of heating the first bearing sleeve and step S214 of heating the second bearing sleeve can be performed simultaneously.

[0090] Based on the above embodiment, the first preset temperature is T1. Specifically, T1 satisfies the following formula:

[0091] T1=(d1-D1) / (a1×D1)+T0

[0092] Wherein, D1 is the inner diameter of the first bearing sleeve 103 (e.g. Figure 6 d1 is the diameter of the first shaft section of the rotor main shaft 101 (as shown in Figure 1 As shown in FIG. 1 , a1 is the material linear expansion coefficient of the first bearing sleeve 103 , and T0 is room temperature. Preferably, the temperature range of T1 is 150° C.-450° C.

[0093] The second preset temperature is T2. Specifically, T2 satisfies the following formula:

[0094] T2=(d2-D2) / (a2×D2)+T0

[0095] Wherein, D2 is the inner diameter of the second bearing sleeve 105 (eg Figure 7 d2 is the diameter of the third shaft section of the rotor main shaft 101 (as shown in Figure 1 As shown), a2 is the material linear expansion coefficient of the second bearing sleeve 105, and T0 is room temperature. Preferably, the temperature range of T2 is 150°C-450°C.

[0096] In a specific embodiment of the present application, step S22, component pressing includes:

[0097] Step S221, compacting once;

[0098] After the heated second bearing sleeve 105 is assembled, the clamping member 106 is assembled on the rotor main shaft 101 and the clamping member 106 is clamped once, and the tightening torque can be selected to be 10Nm-20Nm. Specifically, the clamping member 106 can be a clamping nut, which can be tightened once by a torque gun.

[0099] Step S222, secondary pressing;

[0100] In order to ensure the clamping force of the clamping piece 106, after the second bearing sleeve 105 cools to room temperature, the clamping piece 106 can be tightened for the second time by a torque gun, and the tightening torque can be selected to be 25Nm-50Nm to ensure the clamping of the first bearing sleeve 103, the rotor magnet 104 and the second bearing sleeve 105 to improve the stability of the rotor shaft structure.

[0101] In order to cooperate with the corresponding parts of the motor and play a sealing role, a labyrinth sealing groove is provided on the rotor main shaft 101.

[0102] In order to improve the assembly accuracy, in a specific embodiment of the present application, after the assembly is pressed in step S22, the following steps are further included:

[0103] Step S23, cutting process;

[0104] The surfaces of the first bearing sleeve 103, the rotor magnet 104, the second bearing sleeve 105 and the rotor magnet sleeve 107 that are in contact with each other are cut so that the outer cylindrical surfaces of the first step ring, the rotor magnet 104 and the second step ring are the same outer cylindrical surface to ensure the stability of the connection between the rotor magnet sleeve 107 and the first bearing sleeve 103, the rotor magnet 104 and the second bearing sleeve 105. Preferably, turning can be used, and the outer diameter coaxiality of the first bearing sleeve 103, the rotor magnet 104 and the second bearing sleeve 105 after turning is ≤0.05, and the total runout is ≤0.05.

[0105] In a specific embodiment of the present application, in order to ensure the combination stability of the rotor magnet sheath 107, the rotor magnet sheath 107 and the rotor magnet 104 are interference fit, and step S30 of assembling the magnet sheath includes:

[0106] Step S31, heating the rotor magnet sheath;

[0107] The rotor magnet sheath 107 may be heated by a heating furnace to a preset temperature;

[0108] Step S32, assembling the heated rotor magnet sheath;

[0109] In order to facilitate the assembly of the rotor magnet cover 107, a positioning tool 108 is used for assembly. Figure 4 and Figure 5 As shown, the positioning fixture 108 has a mounting through hole, and the mounting through hole includes a first hole section and a second hole section, and a positioning step 1081 is formed between the first hole section and the second hole section. The semi-finished rotor shaft assembly is inserted into the mounting through hole of the positioning fixture 108, so that the first step ring abuts against the positioning step 1081. The rotor magnet 104 is located in the first hole section. In order to facilitate the assembly of the rotor magnet sleeve 107, the gap between the rotor magnet 104 and the first hole section is not less than the thickness of the rotor magnet sleeve 107. The heated rotor magnet sleeve 107 is assembled in the gap between the rotor magnet 104 and the first hole section until it abuts against the positioning step 1081. The setting of the positioning fixture 108 facilitates the assembly and positioning of the rotor magnet sleeve 107, which can improve the assembly accuracy and shorten the assembly time.

[0110] In order to ensure the coaxiality of the first bearing sleeve 103 and the second bearing sleeve 105 and the overall accuracy of the rotor shaft, step S40 is also included, in which the outer surfaces of each shaft section of the rotor shaft are integrally fine-ground with the two ends of the rotor shaft as the positioning reference. Preferably, the outer diameter coaxiality of the first bearing sleeve 103 and the second bearing sleeve 105 after fine grinding should be ensured to be ≤0.005.

[0111] In order to facilitate the connection between the rotor shaft assembly and the motor, connecting threads are provided at both ends of the rotor main shaft 101 .

[0112] This embodiment also discloses an air compressor, including a housing, in which a rotor shaft assembly is installed. The rotor shaft assembly is assembled using the air compressor main shaft assembly method disclosed in the above embodiment.

[0113] In a specific embodiment of the present application, the air compressor includes a shell 901, a pressure end and a turbine end. A rotor shaft assembly 903 is arranged in the shell 901. The pressure end is arranged at one end of the shell 901, and is used to provide compressed air for the fuel cell. The pressure end is provided with a pressure wheel 902, and the pressure wheel 902 is fixed to one end of the rotor shaft assembly 903 close to the pressure end. The turbine end is arranged at the other end of the shell 901, and is used to recover the exhaust gas generated by the fuel cell reaction. The turbine end is provided with a turbine 109, and the turbine 109 is fixed to one end of the rotor shaft assembly 903 close to the turbine end; the rotor shaft assembly 903 is abutted with the turbine 106, and the abutting ends of the rotor shaft assembly 903 and the turbine 109 are surrounded by a groove 904 arranged in a radially concave manner.

[0114] The exhaust gas generated by the fuel cell enters from the turbine end, driving the turbine to rotate, the turbine drives the rotor shaft assembly 904 to rotate, and the rotor shaft assembly 904 drives the pressure wheel 902 to rotate, thereby compressing air and providing it to the fuel cell. The air compressor disclosed in the embodiment of the present application can utilize the energy of the exhaust gas and reduce energy waste.

[0115] A groove 904 is set at the abutting position of the rotor shaft assembly 903 and the turbine 109, specifically by a clamping piece 106 that can clamp the various components of the rotor shaft assembly 903. The clamping piece 106 preferably adopts a clamping nut, and a groove 904 is formed at the abutting position with the turbine 109. Through the rotation of the rotor, the centrifugal force is used to throw out the cooling deposited water droplets in the groove, forming a water throwing trough structure, reducing the risk of condensed water entering the interior of the motor and improving the performance of the air compressor.

[0116] In this embodiment, the back side of the turbine 109 is a guide slope 1091 that forms a groove, the end of the clamping piece 106 is a guide slope 1061, the guide slope 1091 and the drainage slope 1061 are connected at the root, and the groove 904 is a water-throwing trough surrounded by the guide slope 1061 and the drainage slope 1091.

[0117] In this embodiment, a support step 1092 protruding from the back side of the turbine 109 is provided at the hub position of the turbine 109 , and the guide slope 1091 is composed of the outer periphery of the support step 1092 and the back end surface of the turbine 109 .

[0118] In this embodiment, the support step 1062 and the pressing member 106 are in abutment with each other, and the groove 904 is arranged at the abutment end of the support step 1092 and the pressing member 106.

[0119] In this embodiment, the drainage slope 1061 of the pressing member 106 and the drainage slope 1091 of the turbine 109 form a water-throwing trough structure, and the cooling water is thrown out by centrifugal force through the rotation of the rotor.

[0120] The above are only preferred implementations of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A method for assembling a main shaft of an air compressor, characterized in that: Includes steps: Processing a rotor main shaft, wherein the rotor main shaft (101) is processed and formed in one piece; Processing a pressing piece, wherein the supporting end of the pressing piece (106) is processed with a drainage slope (1061) arranged obliquely from the outer circumference to the end; Assembling the components, the first bearing sleeve (103), the rotor magnet (104) and the second bearing sleeve (105) are sequentially sleeved on the rotor main shaft (101), the first bearing sleeve (103) and the second bearing sleeve (105) are both interference fit with the rotor main shaft (101), and a semi-finished rotor shaft component is obtained; The rotor magnet sheath is assembled, and the rotor magnet sheath (107) is assembled on the outside of the rotor magnet (104), and the rotor magnet sheath (107) and the rotor magnet (104) are interference-fitted.

2. The air compressor main shaft assembly method according to claim 1, characterized in that: An axial positioning member (102) is provided on the rotor main shaft (101), and a side of the first bearing sleeve (103) facing away from the rotor magnet (104) is positioned by the axial positioning member (102).

3. The air compressor main shaft assembly method according to claim 2, characterized in that: A first step ring is provided on one end of the first bearing sleeve (103) close to the rotor magnet (104), a second step ring is provided on one end of the second bearing sleeve (105) close to the rotor magnet (104), and the rotor magnet sleeve (107) is interference-connected to the first step ring, the rotor magnet (104) and the second step ring.

4. The method for assembling the main shaft of an air compressor according to claim 3, characterized in that: The component assembly steps specifically include: Assembling the components, the first bearing sleeve (103), the rotor magnet (104) and the second bearing sleeve (105) are sequentially sleeved on the rotor main shaft (101), and the first bearing sleeve (103) is positioned on the axial positioning member (102); The assembly is compressed, and a compression piece (106) is assembled on the rotor main shaft (101) to compress the side of the second bearing sleeve (105) facing away from the rotor magnet (104).

5. The method for assembling the main shaft of an air compressor according to claim 4, characterized in that: The component assembly step includes: Heating the first bearing sleeve, heating the first bearing sleeve (103) to a first preset temperature; Assembling the heated first bearing sleeve, and assembling the heated first bearing sleeve (103) on the rotor main shaft (101) so that the first bearing sleeve (103) fits the axial positioning member (102); Assembling the rotor magnet, and assembling the rotor magnet (104) on the rotor main shaft (101) so that the first end of the rotor magnet (104) abuts against the first step ring; Heating the second bearing sleeve, heating the second bearing sleeve (105) to a second preset temperature; The heated second bearing sleeve is assembled, and the heated second bearing sleeve (105) is assembled on the rotor main shaft (101), so that the second step ring abuts against the second end of the rotor magnet (104).

6. The method for assembling the main shaft of an air compressor according to claim 5, characterized in that: The first preset temperature is T1, and T1 satisfies the following formula: T1=(d1-D1) / (a1×D1)+T0 In the formula, D1 is the inner hole diameter of the first bearing sleeve (103), d1 is the diameter of the shaft section of the rotor main shaft (101) and the inner hole of the first bearing sleeve 103, a1 is the material linear expansion coefficient of the first bearing sleeve (103), and T0 is the room temperature.

7. The method for assembling the main shaft of an air compressor according to claim 5, characterized in that: The second preset temperature is T2, and T2 satisfies the following formula: T2=(d2-D2) / (a2×D2)+T0 In the formula, D2 is the inner hole diameter of the second bearing sleeve (105), d2 is the diameter of the shaft section of the rotor main shaft (101) and the inner hole of the second bearing sleeve (105), a2 is the material linear expansion coefficient of the second bearing sleeve (105), and T0 is the room temperature.

8. The method for assembling the main shaft of an air compressor according to claim 5, characterized in that: The component pressing step comprises: After the heated second bearing sleeve (105) is assembled, the pressing member (106) is tightened once, with a tightening torque of 10Nm-20Nm; Secondary tightening: After the second bearing sleeve (105) cools to room temperature, the clamping member (106) is tightened for a second time, with a tightening torque of 25Nm-50Nm.

9. The method for assembling the main shaft of an air compressor according to claim 8, characterized in that: After the assembly pressing step, the step of: Cutting is performed on the outer surfaces of the first bearing sleeve (103), the rotor magnet (104), and the second bearing sleeve (105) that are in contact with the rotor magnet sleeve (107).

10. The method for assembling the main shaft of an air compressor according to claim 3, characterized in that: The steps for assembling the rotor magnet cover include: heating the rotor magnet sheath; Assemble the heated rotor magnet sleeve, position the semi-finished rotor shaft assembly in a positioning tool (108), wherein the positioning tool (108) has a mounting through hole, wherein the mounting through hole includes a first hole section and a second hole section, wherein a positioning step (1081) is formed between the first hole section and the second hole section, insert the semi-finished rotor shaft assembly into the mounting through hole, wherein the first step ring abuts against the positioning step (1081), the rotor magnet (104) is located in the first hole section, and the gap between the rotor magnet (104) and the first hole section is not less than the thickness of the rotor magnet sleeve (107), and assemble the heated rotor magnet sleeve (107) in the gap until it abuts against the positioning step (1081).

11. An air compressor, characterized in that: include: A housing (901), wherein a rotor shaft assembly (903) assembled by the air compressor main shaft assembly method according to any one of claims 1 to 10 is arranged in the housing (901); A pressure end, arranged at one end of the housing (901), used for providing compressed air for the fuel cell, the pressure end being provided with a pressure wheel (902), and the pressure wheel (902) being fixed to one end of the rotor shaft assembly (903) close to the pressure end; A turbine end, arranged at the other end of the housing (901), for recovering exhaust gas generated by a fuel cell reaction, wherein the turbine end is provided with a turbine (109), and the turbine (109) is fixed to one end of the rotor shaft assembly (903) close to the turbine end; The rotor shaft assembly (903) is in abutment with the turbine (109), and the abutment ends of the rotor shaft assembly (903) and the turbine (109) form a groove (904) that is concavely arranged in the radial direction.

12. The air compressor according to claim 10, characterized in that: The back side of the turbine (109) is a flow guide slope (1091) that surrounds the groove (904); the flow guide slope (1091) and the drainage slope (1061) are connected at the root; and the groove (904) is a water-throwing trough surrounded by the flow guide slope (1061) and the drainage slope (1091).

13. The air compressor according to claim 12, characterized in that: A support step (1092) protruding from the back side of the turbine is arranged at the hub position of the turbine (109), and the guide slope (1091) is composed of the outer periphery of the support step (1092) and the back end face of the turbine (109).

14. The air compressor according to claim 13, characterized in that: The support step (904) and the pressing piece (106) are in abutment with each other, and the groove (904) is arranged at the abutment end of the support step (1092) and the pressing piece (106).

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