Tangential key structure and compressor

Abstract

The utility model provides a tangential key structure and a compressor, the tangential key structure comprises a first tangential key and a second tangential key, the first tangential key is used for being arranged on an impeller, the second tangential key is used for being arranged on a rotating shaft, the first tangential key is provided with a first abutting surface, the second tangential key is provided with a second abutting surface, and the first abutting surface and the second abutting surface are arranged on the rotating shaft. The first abutting face and the second abutting face abut against each other in the axial direction and the circumferential direction of the rotating shaft. According to the tangential key structure and the compressor provided by the embodiment of the utility model, the first tangential key is arranged on the impeller, the second tangential key is arranged on the rotating shaft, and the first abutting surface of the first tangential key abuts against the second abutting surface of the second tangential key in the axial direction and the circumferential direction of the rotating shaft; the fixed connection between the rotating shaft and the impeller can be realized, and the torque can be stably transmitted.

Description

Technical Field

[0001] This application belongs to the technical field of compressors, and particularly relates to a tangential key structure and a compressor. Background Art

[0002] Compressors generally include an impeller and a main shaft. The assembly structure between the impeller and the main shaft is usually a large interference fit without a key or a small interference fit with a key. Both of these transmission forms can meet the torque transmission of the impeller while ensuring no loosening.

[0003] However, in the prior art, for a small-sized rotor without a spacer sleeve with a compact structure, there is a situation where the hub thickness of the impeller does not meet the requirements for keyway machining, or due to installation direction and structural limitations, single or double key fits cannot meet the axial positioning of the impeller. If a large interference fit without a key is used, since the main shaft is relatively thin, it is easy to cause the problem of bending deformation of the main shaft after assembly. Utility Model Content

[0004] Therefore, the technical problem to be solved by this application is to provide a tangential key structure and a compressor, which can improve the connection strength and stability between the impeller and the main shaft.

[0005] To solve the above problems, this application provides a tangential key structure, including a first tangential key and a second tangential key. The first tangential key is used to be arranged on the impeller, and the second tangential key is used to be arranged on the rotating shaft. A first abutting surface is arranged on the first tangential key, and a second abutting surface is arranged on the second tangential key. The first abutting surface abuts against the second abutting surface in the axial direction and circumferential direction of the rotating shaft.

[0006] Optionally, the cross-section of the first tangential key increases along the rotation direction of the impeller, and the cross-section of the second tangential key decreases along the rotation direction of the rotating shaft.

[0007] Optionally, the first tangential key is arranged in the shaft hole of the impeller and protrudes inward along the radial direction, and the second tangential key is arranged on the outer peripheral wall of the rotating shaft and protrudes outward along the radial direction.

[0008] Optionally, the impeller is sleeved on the rotating shaft along a first direction. After the first tangential key abuts against the second tangential key, the first tangential key is in the first direction of the second tangential key.

[0009] Optionally, the shaft hole of the impeller includes a first hole section and a second hole section. The first hole section and the second hole section are arranged along the axial direction of the impeller. The aperture of the first hole section is larger than that of the second hole section. The first tangential key is arranged on the hole wall of the first hole section. The outer wall of the first tangential key close to the central axis of the shaft hole is an arc surface, and the diameter of the circle where it is located is the same as the diameter of the second hole section. The difference between the diameter of the first hole section and the diameter of the second hole section is 1-3 mm.

[0010] Optionally, there are multiple first tangential keys, and the multiple first tangential keys are evenly arranged along the circumferential direction of the impeller. There are multiple second tangential keys, and the multiple first tangential keys are evenly arranged along the circumferential direction of the impeller. The number of the first tangential keys and the number of the second tangential keys are even numbers. The number of the first tangential keys and the number of the second tangential keys do not exceed eight. The first tangential keys and the second tangential keys are arranged in one-to-one correspondence.

[0011] Optionally, the first tangential key extends in an arc along the circumferential direction of the impeller, and the central angle corresponding to the formed arc is 19°-21°. The second tangential key extends in an arc along the circumferential direction of the rotating shaft, and the central angle corresponding to the formed arc is 19°-21°. The angle formed by the first abutting surface and the plane perpendicular to the central axis of the impeller is 7°-9°. The angle formed by the second abutting surface and the plane perpendicular to the central axis of the rotating shaft is 7°-9°.

[0012] Optionally, the rotating shaft includes a first shaft section and a second shaft section. The first shaft section and the second shaft section are arranged along the axial direction of the rotating shaft. The outer diameter of the first shaft section is larger than that of the second shaft section to form a positioning step on the outer peripheral wall of the rotating shaft. The positioning step is used to abut against the end of the impeller. When the positioning step abuts against the end of the impeller, the first abutting surface and the second abutting surface are opposite in the circumferential direction of the rotating shaft.

[0013] Optionally, the outer wall of the second tangential key away from the central axis of the rotating shaft is an arc surface, and the diameter of the circle where it is located is smaller than the outer diameter of the first shaft section and the diameter of the circle where the root of the first tangential key is located. The diameter of the relief circle of the second tangential key is the same as the diameter of the circle where the root of the second tangential key is located. The second shaft section includes a first sleeved section and a second sleeved section. The first sleeved section is arranged in the first hole section, and the second sleeved section is arranged in the second hole section. The second tangential key is arranged on the first sleeved section. The diameter of the relief circle of the second tangential key is larger than the diameter of the second sleeved section, and the difference is 1-3 mm. The difference between the outer diameter of the first shaft section and the diameter of the second sleeved section is 3-5 mm. The rotating shaft and the impeller are in interference fit, and the interference amount is 0.1%-0.2%.

[0014] On the other hand of the present application, a compressor is provided, which includes the tangential key structure as described above.

[0015] Beneficial effects

[0016] In an embodiment of the present utility model, a tangential key structure and a compressor are provided. In the tangential key structure, a first tangential key is arranged on the impeller, a second tangential key is arranged on the rotating shaft, and the first abutting surface of the first tangential key abuts against the second abutting surface of the second tangential key in the axial direction and circumferential direction of the rotating shaft, so as to realize the fixed connection between the rotating shaft and the impeller and stably transmit torque. Description of the drawings

[0017] Figure 1 It is a schematic structural diagram of the impeller of the embodiment of the present application;

[0018] Figure 2 is Figure 1 a schematic structural diagram of the shaft hole at the A direction in ;

[0019] Figure 3 It is a schematic structural diagram of the rotating shaft of the embodiment of the present application;

[0020] Figure 4 It is a three-dimensional structural diagram of the impeller of the embodiment of the present application;

[0021] Figure 5 It is a schematic structural diagram of the first state when the rotating shaft and the impeller are assembled in the embodiment of the present application;

[0022] Figure 6 It is a schematic structural diagram of the second state when the rotating shaft and the impeller are assembled in the embodiment of the present application.

[0023] The reference signs are represented as:

[0024] 1, first tangential key; 11, first abutting surface; 2, second tangential key; 21, second abutting surface; 3, impeller; 31, first hole section; 32, second hole section; 4, rotating shaft; 41, first shaft section; 42, second shaft section; 43, positioning step. Specific embodiments

[0025] In the description of the present application, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present utility model.

[0026] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, "a plurality" means two or more unless otherwise specifically defined.

[0027] In the present application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected to", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0028] The preferred embodiments of the present utility model will be described below with reference to the drawings. It should be understood that the preferred embodiments described herein are only for the purpose of illustrating and explaining the present utility model and are not used to limit the present utility model.

[0029] Referring jointly to Figures 1 to 6 As shown, according to an embodiment of the present application, a tangential key structure is provided, which includes a first tangential key 1 and a second tangential key 2. The first tangential key 1 is used to be arranged on an impeller 3, and the second tangential key 2 is used to be arranged on a rotating shaft 4. A first abutting surface 11 is arranged on the first tangential key 1, and a second abutting surface 21 is arranged on the second tangential key 2. The first abutting surface 11 and the second abutting surface 21 abut against each other in the axial direction and circumferential direction of the rotating shaft 4.

[0030] By arranging the first tangential key 1 on the impeller 3, arranging the second tangential key 2 on the rotating shaft 4, and making the first abutting surface 11 of the first tangential key 1 and the second abutting surface 21 of the second tangential key 2 abut against each other in the axial direction and circumferential direction of the rotating shaft 4, a fixed connection between the rotating shaft 4 and the impeller 3 can be realized and torque can be stably transmitted.

[0031] Among them, the impeller 3 and the rotating shaft 4 can be the impeller 3 and the rotating shaft 4 in the compressor, that is, the tangential key structure in this embodiment can be applied to the installation of the impeller 3 and the rotating shaft 4 in the compressor.

[0032] Among them, the first tangential key 1 is milled on the impeller 3, and the second tangential key 2 is milled on the rotating shaft 4.

[0033] Among them, the first abutting surface 11 and the second abutting surface 21 are adapted to each other so that the first abutting surface 11 and the second abutting surface 21 are closely attached.

[0034] Specifically, the first abutting surface 11 and the second abutting surface 21 are adapted planes or curved surfaces, and both the first abutting surface 11 and the second abutting surface 21 are arranged at an angle other than 90° with respect to the central axis of the rotating shaft 4, so that the first abutting surface 11 and the second abutting surface 21 are closely attached in the axial direction and circumferential direction of the rotating shaft 4.

[0035] More specifically, in this embodiment, both the first abutting surface 11 and the second abutting surface 21 are planes, and the first abutting surface 11 and the second abutting surface 21 are parallel to each other, and the shape and size of the first abutting surface 11 and the second abutting surface 21 are the same, so that the first abutting surface 11 and the second abutting surface 21 are abutted correspondingly.

[0036] The cross-section of the first tangential key 1 increases along the rotation direction of the impeller 3, and the cross-section of the second tangential key 2 decreases along the rotation direction of the rotating shaft 4. It can also be understood that the direction of the first tangential key 1 is opposite to the rotation direction of the rotor, and the direction of the second tangential key 2 is the same as the rotation direction of the rotor, so that the first tangential key 1 and the second tangential key 2 have good structural strength.

[0037] Among them, the longitudinal cross-sections of the first tangential key 1 and the second tangential key 2 are generally trapezoidal. In this embodiment, the longitudinal cross-sections of the first tangential key 1 and the second tangential key 2 are generally right-angled trapezoids.

[0038] Specifically, the first abutting surface 11 is the inclined waist of the formed right-angled trapezoid, the right-angled waist of the right-angled trapezoid is perpendicular to the central axis of the impeller 3, and the upper base and the lower base of the right-angled trapezoid are parallel to the central axis of the impeller 3. The second abutting surface 21 is the inclined waist of the formed right-angled trapezoid, the right-angled waist of the right-angled trapezoid is perpendicular to the central axis of the rotating shaft 4, and the upper base and the lower base of the right-angled trapezoid are parallel to the central axis of the rotating shaft 4. The above perpendicularity is a skew perpendicularity, and after being projected onto a plane, it is a perpendicular relationship.

[0039] Specifically, the upper base of the right-angled trapezoid formed by the longitudinal cross-section of the first tangential key 1 is opposite to the lower base of the right-angled trapezoid formed by the longitudinal cross-section of the second tangential key 2 in the axial direction of the rotating shaft 4, and the lower base of the right-angled trapezoid formed by the longitudinal cross-section of the first tangential key 1 is opposite to the upper base of the right-angled trapezoid formed by the longitudinal cross-section of the second tangential key 2 in the axial direction of the rotating shaft 4.

[0040] The first tangential key 1 is arranged in the shaft hole of the impeller 3 and protrudes inward in the radial direction. The second tangential key 2 is arranged on the outer peripheral wall of the rotating shaft 4 and protrudes outward in the radial direction, so that the first tangential key 1 and the second tangential key 2 can be in close contact with each other.

[0041] Among them, the first tangential key 1 protrudes inward in the radial direction, that is, the first tangential key 1 protrudes toward the central axis direction of the shaft hole of the impeller 3. The second tangential key 2 protrudes outward in the radial direction, that is, the second tangential key 2 protrudes away from the central axis direction of the rotating shaft 4.

[0042] Among them, the first tangential key 1 is arranged on the inner peripheral wall of the shaft hole of the impeller 3, and the second tangential key 2 is arranged on the outer peripheral wall of the rotating shaft 4.

[0043] The impeller 3 is sleeved on the rotating shaft 4 in the first direction. After the first tangential key 1 and the second tangential key 2 are in contact with each other, the first tangential key 1 is in the first direction of the second tangential key 2. Furthermore, the first tangential key 1 can be clamped and fixed by the rotating shaft 4 and the second tangential key 2, ensuring good connection stability.

[0044] Among them, the first direction is parallel to the axial direction of the rotating shaft 4 and the impeller 3.

[0045] Among them, as Figure 5 shown, when the impeller 3 is sleeved on the rotating shaft 4 in the first direction, the first tangential key 1 and the second tangential key 2 are offset in the first direction. As Figure 6 shown, when the sleeving is in place, the rotating shaft 4 and the impeller 3 are relatively rotated, so that the first tangential key 1 and the second tangential key 2 are in contact with each other. After the contact is in place, the first tangential key 1 is in the first direction of the second tangential key 2.

[0046] The shaft hole of the impeller 3 includes a first hole section 31 and a second hole section 32. The first hole section 31 and the second hole section 32 are arranged along the axial direction of the impeller 3. The aperture of the first hole section 31 is larger than the aperture of the second hole section 32. The first tangential key 1 is arranged on the hole wall of the first hole section 31. The outer wall of the first tangential key 1 close to the central axis of the shaft hole is an arc surface, and the diameter of the circle where it is located is the same as the diameter of the second hole section 32, that is, the diameter of the circle where the outer wall of the first tangential key 1 close to the central axis of the shaft hole is located is the same as the diameter of the second hole section 32, which can realize milling out the first tangential key 1 on the first hole section 31 and enable the first tangential key 1 to be in contact with the second tangential key 2, thereby realizing the connection and fixation of the impeller 3 and the rotating shaft 4.

[0047] Among them, the first hole section 31 and the second hole section 32 are coaxially arranged.

[0048] Among them, when the rotating shaft 4 is inserted into the shaft hole, it is first inserted into the first hole section 31 and then into the second hole section 32.

[0049] Among them, the first tangential key 1 is integrally arc-shaped, and the outer wall of the first tangential key 1 close to the central axis of the shaft hole is also an arc surface.

[0050] Among them, the circle where the arc-shaped outer wall of the first tangential key 1 close to the central axis of the shaft hole is located can be called the inner hole circle of the first tangential key 1.

[0051] Specifically, as Figure 1 shown, the diameter of the circle where the arc-shaped outer wall of the first tangential key 1 close to the central axis of the shaft hole is located and the diameter of the second hole section 32 are Φ1. The diameter of the first hole section 31 is Φ2.

[0052] Among them, the diameter of the second hole section 32 is equal to the diameter of the clearance circle between the first hole section 31 and the first tangential key 1, and is also equal to the diameter of the circle where the root of the first tangential key 1 is located.

[0053] Among them, the difference between the diameter of the first hole section 31 and the diameter of the second hole section 32 is 1 - 3 mm.

[0054] Specifically, the difference between the diameter of the first hole section 31 and the diameter of the second hole section 32 is 2 mm.

[0055] The number of the first tangential keys 1 is multiple, and the multiple first tangential keys 1 are evenly arranged along the circumferential direction of the impeller 3. The number of the second tangential keys 2 is multiple, and the multiple first tangential keys 1 are evenly arranged along the circumferential direction of the impeller 3, which can make the torque distribution more uniform and ensure good stability.

[0056] Among them, the number of the first tangential keys 1 and the number of the second tangential keys 2 are even numbers.

[0057] Specifically, the number of the first tangential keys 1 and the number of the second tangential keys 2 do not exceed eight.

[0058] In this embodiment, the number of the first tangential keys 1 and the number of the second tangential keys 2 are both four.

[0059] Among them, the first tangential keys 1 and the second tangential keys 2 are arranged in one-to-one correspondence, and one first tangential key 1 is in contact with one second tangential key 2.

[0060] As Figure 2 shown, the first tangential key 1 extends in an arc shape along the circumferential direction of the impeller 3, and the central angle γ corresponding to the formed arc is 19° - 21°. Specifically, in this embodiment, the central angle γ is 20°.

[0061] The second tangential key 2 extends in an arc shape along the circumferential direction of the rotating shaft 4, and the central angle corresponding to the formed arc is 19° - 21°. Specifically, in this embodiment, the central angle is 20°.

[0062] As Figure 1As shown, the angle α formed by the first abutting surface 11 and the plane perpendicular to the central axis of the impeller 3 is 7° to 9°. Specifically, in this embodiment, the angle α is 8°.

[0063] Among them, the angle formed by the first abutting surface 11 and the plane perpendicular to the central axis of the impeller 3 is also the angle formed by the inclined waist and the right-angled waist in the right trapezoid formed by the longitudinal section of the first tangential key 1.

[0064] As Figure 3 shown, the angle β formed by the second abutting surface 21 and the plane perpendicular to the central axis of the rotating shaft 4 is 7° to 9°. Specifically, in this embodiment, the angle β is 8°.

[0065] Among them, the angle formed by the second abutting surface 21 and the plane perpendicular to the central axis of the impeller 3 is also the angle formed by the inclined waist and the right-angled waist in the right trapezoid formed by the longitudinal section of the second tangential key 2.

[0066] It should be noted that the cross-section is the section perpendicular to the central axis, and the longitudinal section is the section parallel to the length direction.

[0067] The rotating shaft 4 includes a first shaft section 41 and a second shaft section 42. The first shaft section 41 and the second shaft section 42 are arranged along the axial direction of the rotating shaft 4. The outer diameter of the first shaft section 41 is greater than the outer diameter of the second shaft section 42 to form a positioning step 43 on the outer peripheral wall of the rotating shaft 4. The positioning step 43 is used to abut against the end of the impeller 3. When the positioning step 43 abuts against the end of the impeller 3, the first abutting surface 11 and the second abutting surface 21 are opposite to each other in the circumferential direction of the rotating shaft 4.

[0068] By providing the first shaft section 41 and the second shaft section 42 and forming the positioning step 43, the positioning step 43 can abut against the end of the impeller 3 to provide a supporting effect, so that the first tangential key 1 can be pressed against the second tangential key 2, ensuring a good connection and limiting effect.

[0069] Among them, the first shaft section 41 and the second shaft section 42 are two axially connected sections of the rotating shaft 4. As Figure 5 and Figure 6 shown, when the impeller 3 is sleeved on the rotating shaft 4, the first shaft section 41 is outside the shaft hole of the impeller 3, the second shaft section 42 is inside the shaft hole of the impeller 3, and the positioning step 43 formed between the first shaft section 41 and the second shaft section 42 abuts against the end face outside the shaft hole of the impeller 3.

[0070] Among them, when the positioning step 43 abuts against the end of the impeller 3, the first abutting surface 11 and the second abutting surface 21 are opposite in the circumferential direction of the rotating shaft 4. Furthermore, by relatively rotating the impeller 3 and the rotating shaft 4, the first abutting surface 11 and the second abutting surface 21 can be made to abut against each other in the circumferential direction of the rotating shaft 4. Since both the first abutting surface 11 and the second abutting surface 21 are inclined with respect to the axial direction of the rotating shaft 4, a relative clamping force can be formed in the axial direction of the rotating shaft 4 in cooperation with the positioning step 43, and the fixed connection and limit between the impeller 3 and the rotating shaft 4 are achieved through the clamping force.

[0071] Among them, the first shaft section 41 and the second shaft section 42 are coaxially arranged.

[0072] Among them, a right-angle transition is formed between the first shaft section 41 and the second shaft section 42, so that the step surface of the positioning step 43 is perpendicular to the axial direction of the rotating shaft 4.

[0073] The outer wall of the second tangential key 2 away from the central axis of the rotating shaft 4 is an arc surface, and the diameter of the circle where it is located is smaller than the outer diameter of the first shaft section 41 and the diameter of the circle where the root of the first tangential key 1 is located.

[0074] Among them, the circle where the outer wall of the second tangential key 2 away from the central axis of the rotating shaft 4 is located can be called the outer circle of the second tangential key 2, that is, the diameter of the outer circle of the second tangential key 2 is smaller than the outer diameter of the first shaft section 41 and is also smaller than the diameter of the circle where the root of the first tangential key 1 is located.

[0075] Specifically, the diameter of the outer circle of the second tangential key 2 is slightly smaller than the diameter of the circle where the root of the first tangential key 1 is located.

[0076] The diameter Φ4 of the relief circle of the second tangential key 2 is the same as the diameter of the circle where the root of the second tangential key 2 is located.

[0077] Among them, in machining, the relief usually refers to the part of the tool that does not perform cutting during the movement process. When machining a key on a shaft, the relief circle generally refers to the circular area formed by the unprocessed parts left on both sides of the keyway to avoid tool interference or facilitate machining operations. The existence of this relief circle can ensure that the tool for machining the keyway has enough space for cutting and tool withdrawal during machining, prevent the tool from colliding or interfering with other parts of the shaft, and thus ensure the smooth progress and quality of machining.

[0078] The second shaft section 42 includes a first socket section and a second socket section. The first socket section is arranged in the first hole section 31, the second socket section is arranged in the second hole section 32, the second tangential key 2 is arranged on the first socket section, the diameter Φ4 of the relief circle of the second tangential key 2 is larger than the diameter Φ3 of the second socket section, and the difference is 1 - 3 mm.

[0079] Specifically, the diameter Φ4 of the clearance circle of the second tangential key 2 is 2 mm larger than the diameter Φ3 of the second socket section.

[0080] The difference between the outer diameter Φ5 of the first shaft section 41 and the diameter Φ3 of the second socket section is 3 to 5 mm.

[0081] Specifically, the outer diameter Φ5 of the first shaft section 41 is larger than the diameter Φ3 of the second socket section, and the difference is 4 mm.

[0082] The rotating shaft 4 and the impeller 3 are in interference fit, and the interference amount is 0.1% to 0.2%.

[0083] Specifically, the interference amount between the rotating shaft 4 and the impeller 3 is 0.15%.

[0084] When assembling the impeller 3 and the rotating shaft 4 in this embodiment, first heat the impeller 3 to expand the shaft hole of the impeller 3 to have enough clearance, and then push the impeller 3 along the axial direction of the rotating shaft 4. As Figure 5 shown, the first tangential key 1 on the impeller 3 and the second tangential key 2 on the rotating shaft 4 are staggered in the axial direction of the rotating shaft 4, and then are pushed into the vacancy between them. When the positioning step 43 abuts against the end of the impeller 3, as Figure 6 shown, rotate the impeller 3 to make the first tangential key 1 fit with the second tangential key 2. When the impeller 3 is completely cooled, the assembly is completed. At this time, a small interference is generated between the impeller 3 and the rotating shaft 4, meeting the installation requirements.

[0085] On the other hand, this embodiment provides a compressor, including the tangential key structure as described above.

[0086] It is easy for those skilled in the art to understand that, on the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0087] The above are only the preferred embodiments of this application, and are not intended to limit this application. Any modifications, equivalent replacements, and improvements made within the spirit and principles of this application shall be included in the protection scope of this application. The above is only the preferred implementation manner of this application. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of this application, several improvements and variations can still be made, and these improvements and variations should also be regarded as the protection scope of this application.

Claims

1. A tangential key structure, characterized in that: The invention comprises a first tangential key (1) and a second tangential key (2), wherein the first tangential key (1) is used to be arranged on an impeller (3), and the second tangential key (2) is used to be arranged on a rotating shaft (4), the first tangential key (1) is provided with a first abutting surface (11), and the second tangential key (2) is provided with a second abutting surface (21), and the first abutting surface (11) and the second abutting surface (21) abut against each other in the axial direction and the circumferential direction of the rotating shaft (4).

2. The tangential key structure according to claim 1, characterized in that: The cross section of the first tangential key (1) increases along the rotation direction of the impeller (3), and the cross section of the second tangential key (2) decreases along the rotation direction of the shaft (4).

3. The tangential key structure according to claim 1, characterized in that: The first tangential key (1) is arranged in the shaft hole of the impeller (3) and protrudes radially inwards, and the second tangential key (2) is arranged on the outer peripheral wall of the rotating shaft (4) and protrudes radially outwards.

4. The tangential key structure according to claim 1, characterized in that: The impeller (3) is sleeved onto the rotating shaft (4) along a first direction, and after the first tangential key (1) abuts against the second tangential key (2), the first tangential key (1) is located in the first direction of the second tangential key (2).

5. The tangential key structure according to claim 1, characterized in that: The shaft hole of the impeller (3) comprises a first hole section (31) and a second hole section (32); the first hole section (31) and the second hole section (32) are arranged along the axial direction of the impeller (3); the hole diameter of the first hole section (31) is larger than the hole diameter of the second hole section (32); the first tangential key (1) is arranged on the hole wall of the first hole section (31); the outer wall of the first tangential key (1) close to the central axis of the shaft hole is an arc surface, and the diameter of the circle in which the first tangential key (1) is located is the same as the diameter of the second hole section (32); The difference between the diameter of the first hole section (31) and the diameter of the second hole section (32) is 1 to 3 mm.

6. The tangential key structure according to claim 1, characterized in that: There are a plurality of first tangential keys (1), and the plurality of first tangential keys (1) are evenly arranged along the circumference of the impeller (3); there are a plurality of second tangential keys (2), and the plurality of first tangential keys (1) are evenly arranged along the circumference of the impeller (3); The number of the first tangential keys (1) and the number of the second tangential keys (2) are an even number; The number of the first tangential keys (1) and the number of the second tangential keys (2) are no more than eight; The first tangential key (1) and the second tangential key (2) are arranged in a one-to-one correspondence.

7. The tangential key structure according to claim 1, characterized in that: The first tangential key (1) extends in an arc shape along the circumference of the impeller (3), and the central angle of the arc is 19° to 21°; the second tangential key (2) extends in an arc shape along the circumference of the rotating shaft (4), and the central angle of the arc is 19° to 21°; The angle formed between the first abutting surface (11) and a plane perpendicular to the central axis of the impeller (3) is 7° to 9°, and the angle formed between the second abutting surface (21) and a plane perpendicular to the central axis of the rotating shaft (4) is 7° to 9°.

8. The tangential key structure according to claim 5, characterized in that: The rotating shaft (4) comprises a first shaft section (41) and a second shaft section (42); the first shaft section (41) and the second shaft section (42) are arranged along the axial direction of the rotating shaft (4); the outer diameter of the first shaft section (41) is larger than the outer diameter of the second shaft section (42), so as to form a positioning step (43) on the outer peripheral wall of the rotating shaft (4); the positioning step (43) is used to abut against the end of the impeller (3); when the positioning step (43) abuts against the end of the impeller (3), the first abutting surface (11) and the second abutting surface (21) are opposite to each other in the circumferential direction of the rotating shaft (4).

9. The tangential key structure according to claim 8, characterized in that: The outer wall of the second tangential key (2) away from the central axis of the rotating shaft (4) is an arc surface, and the diameter of the circle on which it is located is smaller than the outer diameter of the first shaft section (41) and the diameter of the circle on which the root of the first tangential key (1) is located; The diameter of the hollow knife circle of the second tangential key (2) is the same as the diameter of the circle where the root of the second tangential key (2) is located; The second shaft section (42) comprises a first sleeve section and a second sleeve section, the first sleeve section is arranged in the first hole section (31), the second sleeve section is arranged in the second hole section (32), the second tangential key (2) is arranged on the first sleeve section, the diameter of the hollow knife circle of the second tangential key (2) is larger than the diameter of the second sleeve section, and the difference is 1 to 3 mm; The difference between the outer diameter of the first shaft section (41) and the diameter of the second sleeve section is 3 to 5 mm; The rotating shaft and the impeller (3) are interference fit, and the interference amount is 0.1% to 0.2%.

10. A compressor, characterized in that: Comprising a tangential key structure as described in any one of claims 1-9.

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