A mechanical seal rotary joint

Abstract

The present invention relates to a mechanically sealed rotary joint, which comprises a central rotating shaft, a retaining spring baffle, an upper mechanical sealing structure, a bearing, a first shaft sealing ring, a housing and a lower mechanical sealing structure; the housing is arranged outside the central rotating shaft, and the first shaft sealing ring is arranged in the middle of the housing and the central rotating shaft; at the end of the central rotating shaft, the upper mechanical sealing structure and the bearing are arranged in sequence from the inside to the outside between the central rotating shaft and the housing, and the retaining spring baffle is arranged at the end of the central rotating shaft to limit the upper mechanical sealing structure on the central rotating shaft; at the other end of the central rotating shaft, the lower mechanical sealing structure is arranged between the central rotating shaft and the housing. The present invention is heat-resistant, has a long service life, has low requirements on the properties of the medium, and has leakage detectability.

Description

Technical Field

[0001] The invention relates to a mechanical equipment component, in particular to a mechanical sealing rotary joint. Background Art

[0002] At present, there are various types of rotary joints on the market, and most of them use soft-connected seals such as O-rings or skeleton oil seals. When this type of seal is used for a long time in the equipment, it is easy to wear or deform due to high temperature caused by rotational friction, causing the seal to fail. Summary of the invention

[0003] In view of the above problems existing in the prior art, the object of the present invention is to provide a mechanically sealed rotary joint, which has the characteristics of high temperature resistance, long service life, detectable leakage and low requirements for sealing medium.

[0004] To achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a mechanically sealed rotary joint, which includes a central rotating shaft, a retaining spring baffle, an upper mechanical sealing structure, a bearing, a first shaft sealing ring, an outer shell and a lower mechanical sealing structure; the outer shell is arranged on the outside of the central rotating shaft, and the first shaft sealing ring is arranged in the middle of the outer shell and the central rotating shaft; at the end of the central rotating shaft, the upper mechanical sealing structure and the bearing are arranged in sequence from the inside to the outside between the central rotating shaft and the outer shell, and the retaining spring baffle is arranged on the end of the central rotating shaft to limit the upper mechanical sealing structure on the central rotating shaft; at the other end of the central rotating shaft, the lower mechanical sealing structure is arranged between the central rotating shaft and the outer shell.

[0005] Furthermore, the upper mechanical sealing structure and the lower mechanical sealing structure both include a moving ring, moving ring graphite, compensation ring graphite, compensation ring, a spring, an outer shell sealing ring and an anti-rotation pin; the moving ring is transitionally fitted with the end of the central rotating shaft, the moving ring graphite is provided on the lower section of the moving ring, and there is an interference fit between the moving ring graphite and the moving ring; the compensation ring graphite is provided at the lower part of the moving ring graphite, and the compensation ring graphite is installed on the compensation ring with an interference fit, the compensation ring is fixed on the outer shell through the anti-rotation pin and is located below the compensation ring, and the outer shell sealing ring is provided between the outer shell and the central rotating shaft; the spring is provided at the lower part of the compensation ring, one end of the spring is fixed to the outer shell, and the other end of the spring contacts with the lower end face of the compensation ring, providing a clamping force for the compensation ring.

[0006] Furthermore, a second shaft sealing ring is provided between the moving ring and the central rotating shaft.

[0007] Furthermore, a dynamic ring sealing ring is provided between the dynamic ring and the dynamic ring graphite.

[0008] Furthermore, a compensation ring sealing ring is installed between the compensation ring graphite and the compensation ring.

[0009] Furthermore, the rotary joint has three channels, the first channel is arranged at the center of the central rotating shaft along the length direction of the central rotating shaft; the second channel is a sealed cavity formed by the central rotating shaft, the outer shell, the upper mechanical sealing structure and the first shaft sealing ring; the third channel is a sealed cavity formed by the central rotating shaft, the outer shell, the lower mechanical sealing structure and the first shaft sealing ring.

[0010] Furthermore, the medium passing through the first channel is gas, and the medium passing through the second and third channels is liquid.

[0011] Furthermore, the inlet and the outlet of the first channel are respectively located at two ends of the central rotating shaft.

[0012] Furthermore, the inlet of the second channel is arranged on the outer shell, and the outlet of the second channel is arranged on the central rotating shaft; the outlet of the second channel is arranged along the length direction of the central rotating shaft, and its length is less than the length of the first channel, and is arranged in parallel with the first channel; and the inlet of the second channel passes through the outer shell and the sealed cavity of the second channel in sequence, and is connected with the top of the outlet of the second channel, and the bottom of the outlet of the second channel is located on the side wall at the other end of the central rotating shaft.

[0013] Furthermore, the inlet of the third channel is arranged on the outer shell, and the outlet of the third channel is arranged on the central rotating shaft; the outlet of the third channel is arranged along the length direction of the central rotating shaft, and its length is less than the length of the outlet of the second channel, and is arranged in parallel with the outlets of the first channel and the second channel; and the inlet of the third channel passes through the outer shell and the sealed cavity of the third channel in sequence, and is connected with the top of the outlet of the third channel, and the bottom of the outlet of the third channel is located on the side wall at the other end of the central rotating shaft.

[0014] Since the present invention adopts the above technical scheme, it has the following advantages: 1. The present invention adopts a mechanical seal to make the rotary joint heat-resistant, have a long service life, and have low requirements on the properties of the medium passing through the rotary joint. 2. The sealing method of the present invention is a tight hard connection, and there is an oil filling hole on the rotary joint, which is convenient for providing lubrication to the mechanical seal and achieving sealing through oil film lubrication. 3. The present invention has leak detectability. In summary, the present invention can be widely used in various mechanical equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0016] Figure 2 It is a schematic diagram of the inlet and outlet structures of the three channels of the present invention;

[0017] Figure 3 is an exploded schematic diagram of a mechanical seal according to an embodiment of the present invention;

[0018] Figure numerals: 1 center shaft, 2 retaining ring baffle, 3 upper mechanical sealing structure, 4 bearing, 5 first shaft sealing ring, 6 housing, 7 lower mechanical sealing structure, 1-1 inlet of the first channel, 1-2 inlet of the second channel, 1-3 inlet of the third channel, 1-4 outlet of the third channel, 1-5 outlet of the second channel, 1-6 outlet of the first channel, 3-1 moving ring, 3-2 second shaft sealing ring, 3-3 moving ring sealing ring, 3-4 moving ring graphite, 3-5 compensation ring graphite, 3-6 compensation ring sealing ring, 3-7 compensation ring, 3-8 spring, 3-9 housing sealing ring, 3-10 anti-rotation pin. DETAILED DESCRIPTION

[0019] In the description of the present invention, it should be understood that the terms "upper", "lower", "inner", "outer" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. The present invention is described in detail below in conjunction with the drawings and embodiments.

[0020] like Figure 1 As shown, the present invention provides a mechanically sealed rotary joint, which includes a central rotating shaft 1, a retaining spring baffle 2, an upper mechanical sealing structure 3, a bearing 4, a first shaft sealing ring 5, a housing 6 and a lower mechanical sealing structure 7. The housing 6 is arranged outside the central rotating shaft 1, and the first shaft sealing ring 5 is arranged in the middle of the housing 6 and the central rotating shaft 1. The housing 6 is a stationary part, and the central rotating shaft 1 is a rotating part. At the end of the central rotating shaft 1, the upper mechanical sealing structure 3 and the bearing 4 are arranged in sequence from the inside to the outside between the central rotating shaft 1 and the housing 6, and the retaining spring baffle 2 is arranged at the end of the central rotating shaft 1 to limit the upper mechanical sealing structure 3 on the central rotating shaft 1. At the other end of the central rotating shaft 1, the lower mechanical sealing structure 7 is arranged between the central rotating shaft 1 and the housing 6.

[0021] The rotary joint of the present invention has three channels. The first channel is arranged at the center of the central rotating shaft 1 along the length direction of the central rotating shaft 1. The inlet 1-1 and the outlet 1-6 of the first channel are respectively located at the two ends of the central rotating shaft 1 (such as Figure 2 The second channel is a sealed cavity composed of the central shaft 1, the housing 6, the upper mechanical seal structure 3 and the first shaft seal ring 5, as shown in FIG. Figure 2As shown, the inlet 1-2 of the second channel is arranged on the housing 6, and the outlet 1-5 of the second channel is arranged on the central shaft 1. The outlet 1-5 is arranged along the length direction of the central shaft 1, and its length is less than that of the first channel, and is arranged in parallel with the first channel; and the inlet 1-2 of the second channel passes through the housing 6 and the sealing cavity of the second channel in sequence, and is connected with the top of the outlet 1-5 of the second channel, and the bottom of the outlet 1-5 of the second channel is located on the side wall of the other end of the central shaft 1. The third channel is a sealing cavity composed of the central shaft 1, the housing 6, the lower mechanical sealing structure 7 and the first shaft sealing ring 5, as shown Figure 2 As shown, the inlet 1-3 of the third channel is arranged on the shell 6, and the outlet 1-4 of the third channel is arranged on the central shaft 1. The outlet 1-4 is arranged along the length direction of the central shaft 1, and its length is less than the length of the outlet 1-5 of the second channel, and is arranged in parallel with the outlets 1-5 of the first channel and the second channel; and the inlet 1-3 of the third channel passes through the shell 6 and the sealed cavity of the third channel in sequence, and is connected with the top of the outlet 1-4 of the third channel, and the bottom of the outlet 1-4 of the third channel is located on the side wall of the other end of the central shaft 1. When the shell 6 is stationary and the central shaft 1 rotates, three non-interfering channels can be combined. The medium that can pass through the first channel is gas, and the medium that can pass through the second and third channels is liquid. In this embodiment, the gas is vacuum and the liquid can be lubricating oil.

[0022] In a preferred embodiment, the upper mechanical seal structure 3 and the lower mechanical seal structure 7 have the same structure, and the upper mechanical seal structure 3 is taken as an example for detailed description. Figure 3 As shown, the upper mechanical sealing structure 3 includes a dynamic ring 3-1, a second shaft sealing ring 3-2, a dynamic ring sealing ring 3-3, a dynamic ring graphite 3-4, a compensation ring graphite 3-5, a compensation ring sealing ring 3-6, a compensation ring 3-7, a spring 3-8, a housing sealing ring 3-9 and an anti-rotation pin 3-10.

[0023] The moving ring 3-1 is transitionally matched with the end of the central rotating shaft 1, and a second shaft sealing ring 3-2 is arranged between the moving ring 3-1 and the central rotating shaft 1. The moving ring graphite 3-4 is arranged on the lower section of the moving ring 3-1, and the moving ring graphite 3-4 and the moving ring 3-1 are interference-fitted, and a moving ring sealing ring 3-3 is arranged between the moving ring 3-1 and the moving ring graphite 3-4, so that there is no leakage between the moving ring graphite 3-4 and the moving ring 3-1. A compensation ring graphite 3-5 is arranged at the lower part of the moving ring graphite 3-4. The compensation ring graphite 3-5 is installed on the compensation ring 3-7 by interference fit. A compensation ring sealing ring 3-6 is installed between the compensation ring graphite 3-5 and the compensation ring 3-7 to prevent leakage between the compensation ring graphite 3-5 and the compensation ring 3-7. The compensation ring 3-7 is fixed on the housing 6 by the anti-rotation pin 3-10. The compensation ring 3-7 is prevented from rotating by the anti-rotation pin 3-10. A housing sealing ring 3-9 is arranged between the housing 6 and the central shaft 1 below the compensation ring 3-7. A spring 3-8 is arranged at the lower part of the compensation ring 3-7. One end of the spring 3-8 is fixed on the housing 6. The other end of the spring 3-8 contacts the lower end surface of the compensation ring 3-7 to provide a pressing force for the compensation ring 3-7.

[0024] When in use, when the central shaft 1 rotates, the dynamic ring 3-1 is driven to rotate through the transition fit between the dynamic ring 3-1 and the central shaft 1, and the second shaft seal ring 3-2 between the central shaft 1 and the dynamic ring 3-1 is used to prevent leakage; the dynamic ring graphite 3-4 is installed on the dynamic ring 3-1 with interference fit; the compensation ring graphite 3-5 is installed on the compensation ring 3-7 with interference fit, and the compensation ring 3-7 is prevented from rotating by the anti-rotation pin 3-10. The mechanical seal generates appropriate pressing force on the contact surface of the rotating dynamic ring 3-1 and the graphite of the compensation ring 3-7 through the push of the spring 3-8 and the pressure of the sealing medium through the compensation ring 3-8 and the shell seal ring 3-9, so that the two end faces are closely attached to maintain a very thin liquid film between the end faces to achieve the purpose of sealing, and realize the performance of long service life, low requirements for the sealed medium, and strong environmental adaptability. This layer of liquid film has fluid dynamic pressure and static pressure, which plays the role of lubrication and pressure balance.

[0025] The above embodiments are only used to illustrate the present invention. The structure, size, location and shape of each component may be changed. On the basis of the technical solution of the present invention, any improvement and equivalent transformation of individual components based on the principle of the present invention should not be excluded from the protection scope of the present invention.

Claims

1. A mechanically sealed rotary joint, Features: It includes a central rotating shaft, a retaining spring baffle, an upper mechanical sealing structure, a bearing, a first shaft sealing ring, a shell and a lower mechanical sealing structure; the shell is arranged outside the central rotating shaft, and the first shaft sealing ring is arranged in the middle of the shell and the central rotating shaft; at the end of the central rotating shaft, the upper mechanical sealing structure and the bearing are arranged in sequence from the inside to the outside between the central rotating shaft and the shell, and the retaining spring baffle is arranged at the end of the central rotating shaft to limit the upper mechanical sealing structure on the central rotating shaft; at the other end of the central rotating shaft, the lower mechanical sealing structure is arranged between the central rotating shaft and the shell; The upper mechanical sealing structure and the lower mechanical sealing structure both include a moving ring, moving ring graphite, compensation ring graphite, compensation ring, a spring, a shell sealing ring and an anti-rotation pin; the moving ring is transitionally fitted with the end of the central rotating shaft, the moving ring graphite is provided on the lower end face of the moving ring, and there is an interference fit between the moving ring graphite and the moving ring; the compensation ring graphite is provided at the lower part of the moving ring graphite, and the compensation ring graphite is installed on the compensation ring with an interference fit, the compensation ring is fixed on the outer shell through the anti-rotation pin and is located below the compensation ring, and the outer shell sealing ring is provided between the outer shell and the central rotating shaft; the spring is provided at the lower part of the compensation ring, one end of the spring is fixed on the outer shell, and the other end of the spring contacts with the lower end face of the compensation ring, providing a clamping force for the compensation ring.

2. The rotary joint according to claim 1, Features: A second shaft sealing ring is arranged between the moving ring and the central rotating shaft.

3. The rotary joint according to claim 1, Features: A dynamic ring sealing ring is arranged between the dynamic ring and the dynamic ring graphite.

4. The rotary joint according to claim 1, Features: A compensation ring seal is installed between the compensation ring graphite and the compensation ring.

5. The rotary joint according to any one of claims 1 to 4, Features: The rotary joint has three channels, the first channel is arranged at the center of the central rotating shaft along the length direction of the central rotating shaft; the second channel is a sealed cavity formed by the central rotating shaft, the outer shell, the upper mechanical sealing structure and the first shaft sealing ring; the third channel is a sealed cavity formed by the central rotating shaft, the outer shell, the lower mechanical sealing structure and the first shaft sealing ring.

6. The rotary joint according to claim 5, Features: The medium passing through the first channel is gas, and the medium passing through the second and third channels is liquid.

7. The rotary joint according to claim 5, Features: The inlet and the outlet of the first channel are respectively located at two ends of the central rotating shaft.

8. The rotary joint according to claim 5, Features: The inlet of the second channel is arranged on the outer shell, and the outlet of the second channel is arranged on the central rotating shaft; the outlet of the second channel is arranged along the length direction of the central rotating shaft, and its length is less than the length of the first channel, and is arranged in parallel with the first channel; and the inlet of the second channel passes through the outer shell and the sealed cavity of the second channel in sequence, and is connected with the top of the outlet of the second channel, and the bottom of the outlet of the second channel is located on the side wall at the other end of the central rotating shaft.

9. The rotary joint according to claim 8, Features: The inlet of the third channel is arranged on the outer shell, and the outlet of the third channel is arranged on the central rotating shaft; the outlet of the third channel is arranged along the length direction of the central rotating shaft, and its length is less than the length of the outlet of the second channel, and is arranged in parallel with the outlets of the first channel and the second channel; and the inlet of the third channel passes through the outer shell and the sealed cavity of the third channel in sequence, and is connected with the top of the outlet of the third channel, and the bottom of the outlet of the third channel is located on the side wall at the other end of the central rotating shaft.

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