Air-tight seal structure for high-speed spindle

Abstract

The application discloses a kind of air seal structures for high-speed spindle, it is related to a sealing structure, including the first end cap and the second end cap by pin fastening connection;It further includes the oil film seal ring, support sleeve, dry gas seal assembly and purge seal ring that are sequentially set in the inside of first end cap;The inner ring of first end cap is provided with first annular air groove, second annular air groove and third annular air groove corresponding with oil film seal ring, dry gas seal assembly and purge seal ring respectively;First end cap is provided with main gas hole being communicated with first annular air groove, second annular air groove and third annular air groove respectively;Second end cap is pressed in the inside of first end cap with purge seal ring, dry gas seal assembly, support sleeve and oil film seal ring.The air seal structure for high-speed spindle provided by the application adopts oil film sealing, dry gas sealing and purge sealing three-stage sealing structure to realize the sealing treatment of spindle, guarantee the reliable and effective of overall sealing.

Description

Technical Field

[0001] This invention relates to a sealing structure, and more specifically to a gas seal structure for a high-speed spindle. Background Technology

[0002] The spindle is the shaft on a machine tool that drives the workpiece or cutting tool to rotate. In a machine tool, it mainly supports transmission components and transmits rotational motion and torque. The spindle's motion accuracy and rigidity are crucial factors in ensuring machining quality and cutting efficiency. However, during machining, floating micro-droplets of water and metal particles may enter the spindle from outside the machine tool. Over time, this accumulation can cause the spindle core to rust or wear, affecting its normal operation and reducing machining accuracy and cutting efficiency. Existing spindle cores cannot have direct contact with components other than bearings during operation, and ordinary sealing structures are insufficient for actual production needs. Micro-droplets of water, metal chips from cutting, and even dust may enter the spindle from the spindle nose, thus affecting its normal operation.

[0003] To address the aforementioned issues, prior art patent application 201711486608.X discloses a spindle air-sealing structure. The extended line of the central axis of the third through hole intersects with the shaft core and forms an intersection point. Therefore, the extended line of the central axis of each third through hole forms an angle with the tangent of each intersection point. Simultaneously, due to the gap between the sealing ring and the shaft core, external air enters the gap through each third through hole on the sealing ring and forms an airflow, which can blow dust off the shaft core to prevent water droplets and metal debris from entering the spindle.

[0004] However, the air-tight structure disclosed in the above technical solution only uses the airflow purging function to clean impurities. For high-speed rotating spindles, its sealing effect still needs to be improved.

[0005] Therefore, how to provide a gas seal structure for high-speed spindles with a more stable and reliable sealing effect is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0006] In view of this, the present invention provides an air-sealed structure for high-speed spindles, which aims to solve the above-mentioned technical problems.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A gas seal structure for a high-speed spindle includes a first end cover and a second end cover fastened together by pins; it also includes an oil film seal ring, a support sleeve, a dry gas seal assembly and a purge seal ring sequentially sleeved inside the first end cover.

[0009] The inner ring of the first end cap has a first annular air groove, a second annular air groove, and a third annular air groove corresponding to the oil film sealing ring, the dry gas sealing assembly, and the purge sealing ring, respectively; the first end cap has a main air hole that communicates with the first annular air groove, the second annular air groove, and the third annular air groove, respectively.

[0010] The second end cap presses the purge sealing ring, the dry gas sealing assembly, the support sleeve, and the oil film sealing ring against the inside of the first end cap.

[0011] Through the above technical solution, the high-speed spindle gas seal structure provided by the present invention adopts a three-stage sealing structure of oil film seal, dry gas seal and purge seal to achieve the sealing treatment of the spindle. The purge seal is used to purge impurities that have entered the interior. The dry gas seal forms a gas film structure and flows out from the purge seal. On the one hand, it improves the purging effect, and on the other hand, it forms a gas film structure to prevent impurities from entering. The oil film seal serves as the final seal to ensure the reliability and effectiveness of the overall seal.

[0012] Preferably, in the above-described gas-tight seal structure for a high-speed spindle, the oil film seal ring includes a rigid support ring fitted inside the inner ring of the first end cover, and a rubber seal ring fixed inside the rigid support ring. The thickness of the rigid support ring is approximately the same as the thickness of the support sleeve. This structural arrangement of the rigid support ring allows the oil film seal ring to move within the gap formed by the stepped surface of the first end cover and the support sleeve, enabling it to operate under high-pressure gas and better cooperate with the spindle for sealing.

[0013] Preferably, in the above-mentioned air-sealing structure for a high-speed spindle, the bottom edge of the rubber sealing ring has a sealing lip that extends inwardly at an angle. The sealing lip is made of a flexible rubber material, which can deform under the movement of the rigid support ring to achieve a better sealing effect.

[0014] Preferably, in the above-mentioned high-speed spindle gas seal structure, the dry gas seal assembly includes a support ring seat, springs, stationary rings, and rotating rings; the inner ring of the support ring seat has a radially inwardly protruding annular frame; there are multiple springs, which are respectively fixed to the top and bottom surfaces of the annular frame; there are two stationary rings, which are respectively fixed to the two ends of two sets of springs; there are two rotating rings, which are respectively rotatably arranged at the two ends of the support ring seat, and the two rotating rings respectively fit against the two stationary rings. The rotating ring in the dry gas seal assembly is fixed to the spindle, and during the spindle rotation and under the action of high-pressure gas, a gap can be formed between the rotating ring and the stationary ring, compressing the springs and forming a dry gas seal space.

[0015] Preferably, in the above-mentioned gas-sealed structure for a high-speed spindle, the two end faces of the support ring seat are provided with multiple venting grooves near their inner rings, and the support ring seat is provided with a gas channel connecting the venting grooves and the second annular gas groove. The design of the venting grooves and gas channel allows high-pressure gas to enter between the moving ring and the stationary ring.

[0016] Preferably, in the above-mentioned air-sealed structure for a high-speed spindle, multiple rolling steel balls are embedded on both end faces of the support ring seat near its outer ring. The moving ring has an annular groove that mates with the rolling steel balls, and multiple spiral channels arranged around it. The cooperation between the rolling steel balls and the annular grooves enables a stable rotational fit between the moving ring and the stationary ring, resulting in greater stability.

[0017] Preferably, in the above-mentioned air-sealed structure for a high-speed spindle, a lubricating oil film is present between the contact surfaces of the two moving rings and the support sleeve and the blow-off sealing ring. The lubricating oil film prevents frictional loss. In this invention, a lubricating oil film can be provided at any rotating position, and corresponding oil inlet channels are opened on the first end cover. However, this is not the focus of this invention and will not be elaborated upon further.

[0018] Preferably, in the above-mentioned air-sealed structure for a high-speed spindle, the inner ring of the purge sealing ring has a trapezoidal groove, and multiple purge air holes penetrating its outer wall are opened in the trapezoidal groove, with the multiple purge air holes arranged spirally. Spiral air intake further improves the ability to remove impurities.

[0019] Preferably, in the above-described gas seal structure for a high-speed spindle, the first annular gas groove, the second annular gas groove, and the third annular gas groove are connected to the main air hole through a first branch air passage, a second branch air passage, and a third branch air passage, respectively. The arrangement of the first branch air passage, the second branch air passage, and the third branch air passage ensures smooth gas flow.

[0020] Preferably, in the above-described gas-sealing structure for a high-speed spindle, the inner diameters of the first, third, and second air passages gradually increase. By setting air passages with different inner diameters, different air pressure requirements can be met.

[0021] As can be seen from the above technical solution, compared with the prior art, the present invention discloses a gas-sealed structure for high-speed spindles, which has the following beneficial effects:

[0022] 1. The high-speed spindle air seal structure provided by the present invention adopts a three-stage sealing structure of oil film seal, dry gas seal and purge seal to achieve the sealing treatment of the spindle, ensuring the reliability and effectiveness of the overall seal.

[0023] 2. The purge seal of the present invention is used to purge impurities that have entered the interior. The dry gas seal forms a gas film structure and flows out from the purge seal. On the one hand, it improves the purging effect, and on the other hand, it forms a gas film structure to prevent impurities from entering. The oil film seal acts as the final seal, with each stage working in turn, with a clear division of labor and stable effect. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0025] Figure 1 A cross-sectional view of the air-tight structure for a high-speed spindle provided by the present invention;

[0026] Figure 2 A cross-sectional view of the first end cap provided for this invention;

[0027] Figure 3 A cross-sectional view of the oil film sealing ring provided by the present invention;

[0028] Figure 4 A cross-sectional view of the dry gas sealing assembly provided by the present invention;

[0029] Figure 5 Provided by the present invention Figure 4 A magnified view of part A in the middle;

[0030] Figure 6 This is a front view of the dynamic ring provided by the present invention;

[0031] Figure 7 Provided by the present invention Figure 6 A magnified view of part B in the middle;

[0032] Figure 8 A cross-sectional view of the purge sealing ring provided by the present invention;

[0033] Figure 9 A cross-sectional view of the air-tight structure for high-speed spindles provided by the present invention connecting the spindle;

[0034] Figure 10 Provided by the present invention Figure 9 Enlarged view of the unventilated area C in the middle section;

[0035] Figure 11 Provided by the present invention Figure 9 Enlarged view of the local C ventilation state.

[0036] in;

[0037] 1-First end cap;

[0038] 11-First annular air groove; 12-Second annular air groove; 13-Third annular air groove; 14-Main air port; 15-First branch air passage; 16-Second branch air passage; 17-Third branch air passage;

[0039] 2-Second end cap;

[0040] 3-Pin;

[0041] 4-Oil film seal ring;

[0042] 5-Support sleeve;

[0043] 51-Rigid support ring; 52-Rubber sealing ring; 53-Sealing lip;

[0044] 6-Dry gas sealing assembly;

[0045] 61-Support ring seat; 611-Annular ring frame; 612-Ventilation groove; 613-Gas passage; 62-Spring; 63-Stationary ring; 64-Moving ring; 641-Annular slide groove; 642-Helical groove; 65-Rolling steel ball;

[0046] 7-Purge the sealing ring;

[0047] 71-Trapezoidal groove; 72-Purge air hole;

[0048] 8-Spindle. Detailed Implementation

[0049] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] See appendix Figure 1 and attached Figure 2 The present invention discloses a gas seal structure for a high-speed spindle, including a first end cover 1 and a second end cover 2 fastened together by a pin 3; and further including an oil film sealing ring 4, a support sleeve 5, a dry gas sealing assembly 6 and a purge sealing ring 7 sequentially sleeved inside the first end cover 1.

[0051] The inner ring of the first end cap 1 is provided with a first annular air groove 11, a second annular air groove 12 and a third annular air groove 13 corresponding to the oil film sealing ring 4, the dry gas sealing component 6 and the purge sealing ring 7 respectively; the first end cap 1 is provided with a main air hole 14 that communicates with the first annular air groove 11, the second annular air groove 12 and the third annular air groove 13 respectively.

[0052] The second end cap 2 presses the purge sealing ring 7, the dry gas sealing assembly 6, the support sleeve 5, and the oil film sealing ring 4 against the inside of the first end cap 1.

[0053] See appendix Figure 3 The oil film sealing ring 4 includes a rigid support ring 51 sleeved on the inner ring of the first end cap 1, and a rubber sealing ring 52 fixed inside the rigid support ring 51. The thickness of the rigid support ring 51 is approximately the same as the thickness of the support sleeve 5.

[0054] To further optimize the above technical solution, the bottom edge of the rubber sealing ring 52 has a sealing lip 53 that extends inwardly.

[0055] See appendix Figure 4 To be continued Figure 6 The dry gas sealing assembly 6 includes a support ring seat 61, springs 62, stationary rings 63 and rotating rings 64; the inner ring of the support ring seat 61 has a radially inwardly protruding annular frame 611; there are multiple springs 62, which are respectively fixed to the top and bottom surfaces of the annular frame 611; there are two stationary rings 63, which are respectively fixed to the two ends of the two sets of springs 62; there are two rotating rings 64, which are respectively rotatably arranged at the two ends of the support ring seat 61, and the two rotating rings 64 are respectively in contact with the two stationary rings 63.

[0056] To further optimize the above technical solution, multiple ventilation grooves 612 are provided on both ends of the support ring seat 61 near its inner ring, and a gas channel 613 is provided on the support ring seat 61 to connect the ventilation grooves 612 and the second annular gas groove 12.

[0057] See appendix Figure 7 Multiple rolling steel balls 65 are embedded on both ends of the support ring seat 61 near its outer ring. The moving ring 64 has an annular groove 641 that cooperates with the rolling steel balls 65. The moving ring 64 has multiple spiral channels 642 arranged around it.

[0058] To further optimize the above technical solution, a lubricating oil film is provided between the mating surfaces of the two moving rings 64 and the support sleeve 5 and the blow-off sealing ring 7.

[0059] See appendix Figure 8 The inner ring of the purge sealing ring 7 has a trapezoidal groove 71, and multiple purge air holes 72 that penetrate its outer wall are provided in the trapezoidal groove 71. The multiple purge air holes 72 are spirally arranged.

[0060] To further optimize the above technical solution, the first annular air groove 11, the second annular air groove 12 and the third annular air groove 13 are respectively connected to the main air hole 14 through the first branch air passage 15, the second branch air passage 16 and the third branch air passage 17.

[0061] To further optimize the above technical solution, the inner diameters of the first airway 15, the third airway 17, and the second airway 16 are gradually increased.

[0062] See appendix Figure 9 This is a schematic diagram of the assembly of the main spindle 8. The main spindle 8 is fitted with the upper part of the first end cover 1. The rotating ring 64 is fixedly sleeved on the main spindle 8. When the main spindle rotates, high-pressure gas is introduced into the main air hole 14. The gas enters the first annular air groove 11 through the first branch air passage 15, pushing the oil film sealing ring 4, so that the sealing lip 53 of the rubber sealing ring 52 fits and seals better with the main spindle.

[0063] Gas enters the second annular gas groove 12 through the second branch gas channel 16, and then enters the ventilation groove 612 through the gas channel 613, causing the stationary ring 63 to push the spring 62, separating the stationary ring 63 and the moving ring 64, forming an air seal. Figure 10 Towards Figure 11 The state changes.

[0064] The gas enters the third annular gas groove 13 through the third branch gas channel 17 and is blown out through the purge gas hole 72 to purge impurities.

[0065] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0066] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A gas-tight structure for a high-speed spindle, comprising a first end cap (1) and a second end cap (2) fastened together by a pin (3); characterized in that, It also includes an oil film sealing ring (4), a support sleeve (5), a dry gas sealing assembly (6) and a purge sealing ring (7) sequentially fitted inside the first end cap (1). The inner ring of the first end cap (1) is provided with a first annular air groove (11), a second annular air groove (12) and a third annular air groove (13) corresponding to the oil film sealing ring (4), the dry gas sealing assembly (6) and the purge sealing ring (7) respectively; the first end cap (1) is provided with a main air hole (14) communicating with the first annular air groove (11), the second annular air groove (12) and the third annular air groove (13) respectively. The second end cap (2) presses the purge sealing ring (7), the dry gas sealing assembly (6), the support sleeve (5) and the oil film sealing ring (4) against the inside of the first end cap (1); The dry gas sealing assembly (6) includes a support ring seat (61), springs (62), stationary rings (63), and moving rings (64); the inner ring of the support ring seat (61) has a radially inwardly protruding annular frame (611); there are multiple springs (62), which are respectively fixed to the top and bottom surfaces of the annular frame (611); there are two stationary rings (63), which are respectively fixed to the two ends of the two sets of springs (62); there are two moving rings (64), which are respectively rotatably arranged at the two ends of the support ring seat (61), and the two moving rings (64) are respectively in contact with the two stationary rings (63); The support ring seat (61) has multiple rolling steel balls (65) embedded on both ends near its outer ring. The moving ring (64) has an annular groove (641) that cooperates with the rolling steel balls (65). The moving ring (64) has multiple spiral channels (642) arranged around it. The support ring seat (61) has multiple ventilation grooves (612) on both ends near its inner ring, and the support ring seat (61) has a gas channel (613) connecting the ventilation grooves (612) and the second annular gas groove (12). The purge seal is used to purge impurities that have entered the interior. The dry gas seal forms a gas film structure and flows out from the purge seal. This improves the purging effect and prevents impurities from entering. The oil film seal serves as the final seal.

2. The gas-sealed structure for a high-speed spindle according to claim 1, characterized in that, The oil film sealing ring (4) includes a hard support ring (51) sleeved on the inner ring of the first end cap (1) and a rubber sealing ring (52) fixed inside the hard support ring (51). The thickness of the hard support ring (51) is approximately the same as the thickness of the support sleeve (5).

3. The gas-sealed structure for a high-speed spindle according to claim 2, characterized in that, The bottom edge of the rubber sealing ring (52) has a sealing lip (53) that extends inwardly.

4. The gas-sealed structure for a high-speed spindle according to claim 1, characterized in that, There is a lubricating oil film between the two moving rings (64) and the mating surfaces of the support sleeve (5) and the purge seal (7).

5. The gas-sealed structure for a high-speed spindle according to claim 1, characterized in that, The inner ring of the purge sealing ring (7) has a trapezoidal groove (71), and a plurality of purge air holes (72) penetrating its outer wall are provided in the trapezoidal groove (71), and the plurality of purge air holes (72) are spirally arranged.

6. A gas-tight seal structure for a high-speed spindle according to any one of claims 1-5, characterized in that, The first annular air groove (11), the second annular air groove (12) and the third annular air groove (13) are respectively connected to the main air hole (14) through the first branch air passage (15), the second branch air passage (16) and the third branch air passage (17).

7. The gas-sealed structure for a high-speed spindle according to claim 6, characterized in that, The inner diameters of the first branch airway (15), the third branch airway (17), and the second branch airway (16) gradually increase.

Images