An inclination angle self-regulating foil end face gas film sealing structure adaptable to forward and reverse rotations

Abstract

An inclination self-regulating foil end face gas film sealing structure adaptable to forward and reverse rotations, comprising a moving ring or a stationary ring of a gas film seal; characterized in that: at least one of the moving ring or the stationary ring is a foil end face seal ring; the foil end face seal ring includes a first foil, a second foil, a fixing pin, a foil fixing seat, a spring, a foil mounting ring, a cam disc, a scroll spring, a ring body and a bolt; the first foil is fixed to the ring body through the fixing pin, and the first foils are evenly arranged in the circumferential direction; the second foil includes a flat foil and a cylindrical foil; the scroll spring twists under the action of torque to realize the relative rotation of the cam disc and the ring body, and the second foil is closely attached to the upper surface of the cam disc under the pulling force of the spring, so that the inclination angle and the inclination direction of the second foil can change with the topography of the upper surface of the contacted cam disc.

Description

Technical Field

[0001] The present invention relates to the technical field of mechanical end face seal structure design, and particularly relates to an inclination angle self-regulating foil end face gas film seal structure adaptable to forward and reverse rotations, and is particularly applicable to shaft end seal devices of various high-speed rotating machines. Background Art

[0002] End face gas film seal is a new type of mechanical seal used for shaft end seals of high-speed rotating machines, and has significant performance advantages of low leakage and long life. At present, the traditional end face gas film seal is a dry gas seal, and the existing dry gas seal technology is prone to instability under high-speed or variable working conditions, resulting in end face deformation and further causing seal failure.

[0003] When the working conditions of the foil end face gas film seal structure change or are disturbed by the outside world, it can realize the change of the film thickness within a small range and reach dynamic equilibrium. In the prior art, most of the foil end face gas film seal structures can only be used in single-direction rotation, and the opening force of the foil cannot be adjusted. However, in engineering practice, the rotational speeds of many rotating machines will change in real time and may reverse. At this time, the traditional foil end face gas film seal structure will have severe friction, and in severe cases, it may cause damage to the seal structure and result in leakage. Summary of the Invention

[0004] The present invention aims to solve the problems of the above-mentioned traditional dry gas seal and foil end face gas film seal, and provides an inclination angle self-regulating foil end face gas film seal structure adaptable to forward and reverse rotations.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] An inclination angle self-regulating foil end face gas film seal structure adaptable to forward and reverse rotations, including a moving ring or a stationary ring of the gas film seal; characterized in that:

[0007] At least one of the dynamic seal ring or the static seal ring is a foil face seal ring; the foil face seal ring includes a first foil, a second foil, a fixing pin, a foil fixing seat, a spring, a foil mounting ring, a cam disc, a scroll spring, a ring body and a bolt; the first foil is fixed to the ring body through the fixing pin, and the first foils are evenly arranged along the circumferential direction; the second foil includes a flat foil and a cylindrical foil, the flat foil is connected to the cylindrical foil by welding, and the cylindrical foils are evenly arranged under the flat foil along the circumferential direction; both left and right ends of the second foil are provided with first spring fixing grooves, both ends of the foil fixing seat are provided with second spring fixing grooves, both ends of the spring are respectively fixed in the first spring fixing groove and the second spring fixing groove, the foil fixing seat and the foil mounting ring are connected by mortise and tenon joints, and a number of first threaded holes are evenly arranged along the circumferential direction on the foil mounting ring; a number of limiting notch openings are evenly formed along the circumferential direction on the cam disc, the cam disc is provided with a mounting groove for mounting the foil mounting ring, and a first scroll spring fixing groove is formed on the inner circumferential surface of the cam disc; a number of inner diameter fixing pin holes and outer diameter fixing pin holes along the radial direction are evenly formed on the circumferential surface of the ring body, the ring body is provided with a circular ring groove as the installation cavity of the scroll spring, a number of second threaded holes are evenly formed along the circumferential direction on the bottom surface of the ring body, the bolt connects the foil mounting ring and the ring body through the first threaded hole, the limiting notch opening and the second threaded hole, a second scroll spring fixing groove is formed on the inner side surface of the circular ring groove, and the circular ring step on the inner diameter side of the ring body serves as a sealing dam; both ends of the scroll spring are respectively installed in the first scroll spring fixing groove and the second scroll spring fixing groove to connect the cam disc and the ring body; the scroll spring twists under the action of torque to realize the relative rotation of the cam disc and the ring body, and the second foil closely adheres to the upper surface of the cam disc under the pulling force of the spring, so that the inclination angle and the inclination direction of the second foil can change with the topography of the upper surface of the cam disc in contact.

[0008] As a preferred technical solution, the fixing pin is of a hollow structure, radial notch openings are provided at both ends of the fixing pin, the depth of the radial notch opening is the radius length of the fixing pin, and a number of axial notch openings are provided between the two radial notch openings on both sides, and the axial notch openings are evenly arranged along the circumferential direction.

[0009] As a preferred technical solution, a number of concave curved surfaces are evenly formed along the circumferential direction on the upper surface of the cam disc, and the number of the concave curved surfaces is an integer multiple of the number of the second foils.

[0010] As a preferred technical solution, the limiting notch openings are symmetrically formed on both sides of the concave curved surface, and the length of the limiting notch opening is less than or equal to the outer diameter arc length of the first foil.

[0011] After adopting the above technical solution, the present invention has the following advantages:

[0012] A tilt self-regulating foil end face gas film seal structure adaptable to forward and reverse rotations of the present invention is used for shaft end seals of rotating machinery. As a dynamic ring in non-contact mechanical seals, it rotates together with the shaft. In the initial state, the scroll spring is in its original length and not under force, and the second foil is in a horizontal state. As the shaft rotates, the cam disc can rotate relative to the ring body under the action of the scroll spring. When the ring body rotates forward, the cam disc rotates in reverse, and the right side of the second foil tilts along the concave surface on the upper surface of the cam disc under the action of the spring; when the ring body rotates in reverse, the cam disc rotates forward, and the left side of the second foil tilts along the concave surface on the upper surface of the cam disc under the action of the spring, realizing that the tilt direction of the foil is adaptively adjusted according to the rotation direction of the rotating machinery, that is, the tilt direction of the second foil always faces the rotation direction of the rotating machinery, which is beneficial to the opening of the end face and realizes non-contact sealing, so as to be applicable to both single-direction and two-direction rotations. In addition, as the rotational speed changes, the deformation amount of the scroll spring changes accordingly, and the rotation amount of the cam disc also changes. And there are limit notches on the cam disc to limit its rotation angle, that is, to control the tilt angle of the second foil within a certain range. The tilt angle of the second foil changes with the rotational speed, realizing that the gas film pressure changes adaptively with the rotational speed, and improving the stability of the rotating machinery seal during high-speed operation and acceleration and deceleration processes.

[0013] A tilt self-regulating foil end face gas film seal structure adaptable to forward and reverse rotations of the present invention, on the one hand, the cam disc plays a role in changing the tilt angle of the foil, and on the other hand, it can provide a rigid support for the foil, ensuring the stiffness of the foil and improving the anti-impact and vibration performance of the foil. The upper layer of the second foil is a flat foil and the lower layer is a cylindrical foil. The cylindrical foil fits on the upper surface of the cam disc and acts as a cam roller. Under the pulling force of the spring, the cylindrical foil always fits on the upper surface of the cam disc, thereby realizing that the tilt angle size and tilt direction of the foil change with the topography of the upper surface of the cam disc. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is an exploded view of a tilt self-regulating foil end face gas film seal structure adaptable to forward and reverse rotations;

[0015] Figure 2 It is a schematic diagram of a partial assembly structure of the foil end face;

[0016] Figure 3 It is a schematic diagram of the structure of the first foil fixing pin;

[0017] Figure 4 It is a schematic diagram of the structure of the cam disc;

[0018] Figure 5 It is the front view of the ring body;

[0019] Figure 6 is Figure 5 the sectional view of the A-A section in

[0020] Figure 7 the top view of the foil end face gas film seal structure;

[0021] Figure 8 is Figure 7 the sectional view of the B-B section in

[0022] Figure 9 the structural schematic diagram of the second foil;

[0023] In the figure:

[0024] 1 - the first foil;

[0025] 2 - the second foil; 201 - the first spring fixing groove; 202 - the flat foil; 203 - the cylindrical foil;

[0026] 3 - the fixing pin; 301 - the radial notch; 302 - the axial notch;

[0027] 4 - the foil fixing seat; 401 - the second spring fixing groove;

[0028] 5 - the spring;

[0029] 6 - the foil installation ring; 601 - the first threaded hole;

[0030] 7 - the cam disc; 701 - the installation groove; 702 - the limit notch; 703 - the upper surface of the cam disc; 7031 - the concave curved surface; 704 - the first scroll spring fixing groove;

[0031] 8 - the scroll spring;

[0032] 9 - the ring body; 901 - the inner diameter fixing pin hole; 902 - the outer diameter fixing pin hole; 903 - the second threaded hole; 904 - the second scroll spring fixing groove; 905 - the circular ring groove; 906 - the sealing dam;

[0033] 10 - the bolt. Specific embodiments

[0034] The following combines the accompanying drawings and specific embodiments to further elaborate on the present invention in detail.

[0035] Refer to Figures 1-9 , a tilt angle self-regulating foil end face gas film seal structure adaptable to forward and reverse rotations, including the moving ring or static ring of the gas film seal; characterized in that:

[0036] At least one of the moving ring or the stationary ring is a foil face seal ring; the foil face seal ring includes a first foil 1, a second foil 2, a fixing pin 3, a foil fixing seat 4, a spring 5, a foil mounting ring 6, a cam disc 7, a scroll spring 8, a ring body 9 and a bolt 10; the first foil 1 is fixed to the ring body 9 by the fixing pin 3, and the first foils 1 are evenly arranged in the circumferential direction; the second foil 2 includes a flat foil 202 and a cylindrical foil 203, the flat foil 202 is connected to the cylindrical foil 203 by welding, and the cylindrical foils 203 are evenly arranged below the flat foil 202 in the circumferential direction; both left and right ends of the second foil 2 are provided with first spring fixing grooves 201, both ends of the foil fixing seat 4 are provided with second spring fixing grooves 401, both ends of the spring 5 are respectively fixed in the first spring fixing groove 201 and the second spring fixing groove 401, the foil fixing seat 4 and the foil mounting ring 6 are connected by mortise and tenon joints, and a plurality of first threaded holes 601 are evenly arranged on the foil mounting ring 6 in the circumferential direction; a plurality of limiting notch openings 702 are evenly formed in the circumferential direction of the cam disc 7, the cam disc 7 is provided with a mounting groove 701 for mounting the foil mounting ring 6, and a first scroll spring fixing groove 704 is formed on the inner circumferential surface of the cam disc 7; a plurality of inner diameter fixing pin holes 901 and outer diameter fixing pin holes 902 in the radial direction are evenly formed on the circumferential surface of the ring body 9, the ring body 9 is provided with a circular ring groove 905 as an installation cavity for the scroll spring 8, a plurality of second threaded holes 903 are evenly formed on the bottom surface of the ring body 9 in the circumferential direction, the bolt 10 connects the foil mounting ring 6 and the ring body 9 through the first threaded hole 601, the limiting notch opening 702 and the second threaded hole 903, a second scroll spring fixing groove 904 is formed on the inner side surface of the circular ring groove 905, and the circular ring step on the inner diameter side of the ring body 9 serves as a sealing dam 906; both ends of the scroll spring 8 are respectively installed in the first scroll spring fixing groove 704 and the second scroll spring fixing groove 904 to connect the cam disc 7 and the ring body 9; the scroll spring 8 realizes the relative rotation of the cam disc 7 and the ring body 9 by being twisted under the action of torque, and the second foil 2 is tightly attached to the upper surface 703 of the cam disc under the pulling force of the spring 5, so that the inclination angle and the inclination direction of the second foil 2 can change with the morphology of the upper surface 703 of the cam disc in contact.

[0037] The fixing pin 3 is of a hollow structure, both ends of the fixing pin 3 are provided with radial notch openings 301, the depth of the radial notch openings 301 is the radius length of the fixing pin 3, and a plurality of axial notch openings 302 are arranged between the two radial notch openings 301, and the axial notch openings 302 are evenly arranged in the circumferential direction.

[0038] A plurality of concave curved surfaces 7031 are evenly formed on the upper surface 703 of the cam disc along the circumferential direction, and the number of the concave curved surfaces 7031 is an integral multiple of the number of the second foils 2. The concave curved surfaces 7031 are smoothly transitioned with the upper surface 703 of the cam disc, and the space curve formed by the intersection of the concave curved surfaces 7031 and the circumferential surface at any radial position where the concave curved surfaces are located is a smooth continuous curve.

[0039] The limiting notch 702 is symmetrically formed on both sides of the concave curved surface 7031, and the arc angle of the limiting notch 702 is less than or equal to the arc angle of the first foil 1.

[0040] The above embodiments are illustrative of the present invention and not restrictive thereof. Any solution obtained by simply transforming the present invention falls within the protection scope of the present invention.

Claims

1. An inclination self-regulating foil end face gas film seal structure adaptable to forward and reverse rotations, comprising a moving ring or a stationary ring of the gas film seal; characterized in that: At least one of the dynamic seal ring or the static seal ring is a foil face seal ring; the foil face seal ring includes a first foil, a second foil, a fixing pin, a foil fixing seat, a spring, a foil mounting ring, a cam disc, a scroll spring, a ring body and a bolt; the first foil is fixed to the ring body through the fixing pin, and the first foils are evenly arranged in the circumferential direction; the second foil includes a flat foil and a cylindrical foil, the flat foil is connected to the cylindrical foil by welding, and the cylindrical foils are evenly arranged under the flat foil in the circumferential direction; both ends of the second foil are provided with first spring fixing grooves, both ends of the foil fixing seat are provided with second spring fixing grooves, and both ends of the spring are respectively fixed in the first spring fixing groove and the second spring fixing groove, the foil fixing seat and the foil mounting ring are connected by mortise and tenon joints, and a plurality of first threaded holes are evenly arranged on the foil mounting ring in the circumferential direction; a plurality of limiting notch openings are evenly formed in the circumferential direction of the cam disc, the cam disc is provided with a mounting groove for mounting the foil mounting ring, and a first scroll spring fixing groove is formed on the inner circumferential surface of the cam disc; a plurality of inner diameter fixing pin holes and outer diameter fixing pin holes in the radial direction are evenly formed on the circumferential surface of the ring body, the ring body is provided with a circular ring groove as the installation cavity of the scroll spring, a plurality of second threaded holes are evenly formed on the bottom surface of the ring body in the circumferential direction, and the bolt connects the foil mounting ring and the ring body through the first threaded hole, the limiting notch opening and the second threaded hole, a second scroll spring fixing groove is formed on the inner side surface of the circular ring groove, and the circular ring step on the inner diameter side of the ring body serves as a sealing dam; both ends of the scroll spring are respectively installed in the first scroll spring fixing groove and the second scroll spring fixing groove to connect the cam disc and the ring body; the scroll spring twists under the action of torque to realize the relative rotation of the cam disc and the ring body, and the second foil is tightly attached to the upper surface of the cam disc under the tension of the spring, so that the inclination angle and the inclination direction of the second foil can change with the topography of the upper surface of the cam disc in contact.

2. The tilt self-regulating foil face gas film seal structure adaptable to forward and reverse rotations according to claim 1, characterized in that: The fixing pin is of a hollow structure, both ends of the fixing pin are provided with radial notch openings, the depth of the radial notch openings is the radius length of the fixing pin, and a plurality of axial notch openings are arranged between the two radial notch openings on both sides, and the axial notch openings are evenly arranged in the circumferential direction.

3. A tilting self-regulating foil end face gas film seal structure adaptable to forward and reverse rotation as described in claim 1, characterized in that: A plurality of concave curved surfaces are evenly formed on the upper surface of the cam disc in the circumferential direction, and the number of the concave curved surfaces is an integer multiple of the number of the second foils.

4. A tilt self-regulating foil end face gas film seal structure adaptable to forward and reverse rotation as described in claim 3, characterized in that: The concave curved surface is smoothly transitioned with the upper surface of the cam disc, and the space curve formed by the intersection of the concave curved surface and the circumferential surface at any radial position where the concave curved surface is located is a smooth and continuous curve.

5. The tilt self-regulating foil end face gas film sealing structure adaptable to forward and reverse rotation according to claim 3, characterized in that: The limiting notch openings are symmetrically arranged on both sides of the concave curved surface, and the arc angle of the limiting notch opening is less than or equal to the arc angle of the first foil.

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