Pin locking device for sealing members of a sealing bushing assembly and method for assembling a sealing bushing
The assembly and disassembly of the sealing bushing assembly are simplified by using a pin locking device. By utilizing the cooperation of the pin and the spring, the problem of complex assembly in the prior art is solved, and a simple and compact sealing bushing assembly is realized.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SIEMENS ENERGY GLOBAL GMBH & CO KG
- Filing Date
- 2021-04-27
- Publication Date
- 2026-05-29
AI Technical Summary
The assembly and disassembly of existing sealing bushing assemblies are complex, requiring specific knowledge and skills, and inaccurate assembly may lead to reduced sealing efficiency or failure.
A pin locking device, including a pin and a spring, is adopted. The pin engages with a removal tool through a longitudinal hole in the pin to achieve detachable connection and fixation of the sealing component, simplifying the assembly process.
It enables simple and compact assembly and disassembly of the sealing bushing assembly, improves assembly efficiency, and avoids seal failure caused by inaccurate assembly.
Smart Images
Figure CN115698564B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the technical field of mechanical seals for machines including rotating components (such as shafts), and more precisely to assemblies of mechanical seals as bushings. Background Technology
[0002] Mechanical seals are mechanical devices designed to help connect mechanical components together to prevent leakage and / or withstand pressure and / or expel contaminants. They are particularly widely used in machines that include rotating components, such as dry gas seals (i.e., mechanical seals that use a sealing gas to create a barrier between the process gas and the atmosphere) equipping most centrifugal gas compressors or gas turbines. Mechanical seals for rotating components, especially dry gas seals, come in many configurations and are typically contained within one or more bushings. For example, a tandem dry gas seal includes a primary seal and a secondary seal within a single bushing, where the secondary seal serves as a backup in case of primary seal failure.
[0003] A sealing bushing can be described as an assembly of a mechanical component, which typically forms a cylindrical hollow body, thus having a cylindrical hollow shape. The hollow portion is configured to receive a shaft or rotating member. The sealing elements of the bushing are arranged against and / or around the shaft or rotating member, and then the cylindrical hollow body is housed within a shaft housing (also referred to as a sealing cavity). The shaft housing is configured to surround the shaft and its annularly arranged bushing, which provides a seal between the shaft and the machine housing. One of the main advantages of using a sealing bushing to seal a shaft is its removability: the sealing bushing is effectively removable within the shaft housing (or sealing cavity), annularly surrounding the shaft, allowing for the removal / replacement of all sealing elements included within the sealing bushing simultaneously, enabling quick assembly / disassembly of the sealing elements.
[0004] Typically, a sealing bushing comprises axially stacked annular sealing elements configured for ring-shaped mounting around an axis (i.e., according to the longitudinal direction of the stack), thus creating the cylindrical hollow shape of the bushing. Within these annular sealing elements (or ring-shaped elements), the following can be distinguished:
[0005] - A housing component, the housing component being an annular sealing component, characterized by having an outer diameter configured to mate with the internal space of a shaft housing; and
[0006] - A bushing component, which is an annular sealing component, characterized by having an inner diameter configured to match the size (i.e., diameter) of a shaft.
[0007] According to a typical bushing configuration, the housing component is radially mounted or positioned on the bushing and is generally designed to hold other annular sealing components (such as stationary sealing rings or clamping rings) in a predetermined position within the bushing, and / or to serve as a support for such annular sealing components. During shaft rotation, the housing component is configured to remain stationary relative to the rotation. As for the bushing, it is configured to enclose the shaft to form a sleeve around the shaft. The bushing can remain stationary or be driven to rotate by the rotation of the shaft. In this case, the bushing rotates together with the shaft at the same angular velocity. The outer and inner diameters of the stacked housing component and bushing define the outer and inner substantially cylindrical surfaces of the sealing sleeve, respectively, which are adapted to the internal space of the shaft housing or sealing cavity of a machine (e.g., a pump or compressor) and to the geometry of the shaft of the machine, such that when the sealing bushing is installed inside the shaft housing, the shaft can be received within the hollow portion of the bushing. Housing components are typically joined or secured to each other by screws and / or bolts to form a whole that surrounds all sealing components, namely the bushing. Typically, radial or axial screws are used for axial or radial connection of housing components and bushing components.
[0008] Existing bushings are complex devices whose assembly and disassembly require specific knowledge and skills to install or remove different bushing annular sealing components. For example, inaccurate assembly of different annular sealing components (e.g., misalignment) can significantly reduce sealing efficiency or lead to failure, such as screw breakage or thread damage. Summary of the Invention
[0009] The object of the present invention is to provide a pin locking device for a sealing component of a sealing bushing assembly and a method for installing the sealing component of a sealing bushing assembly. The pin locking device and method facilitate the assembly and disassembly of the sealing bushing and provide a simpler and more compact bushing, thereby simplifying the manufacture of the bushing assembly.
[0010] This objective is achieved by the measures taken according to the independent claim. Further advantageous embodiments are proposed by the dependent claims.
[0011] This invention relates to a pin-locking device for joining and securing two sealing components of a sealing bushing together. The sealing bushing is configured to provide a seal between a rotatable shaft typically equipped in a machine (such as a compressor) and the shaft housing of such a machine. As known in the prior art, the shaft housing is configured to surround and enclose the sealing bushing, which is mounted annularly around a shaft typically centered within its housing. The sealing bushing particularly has a substantially hollow shape, preferably substantially cylindrical, about a longitudinal axis A passing through the center of the sealing bushing and corresponding to the axis of rotation of the shaft when the sealing bushing surrounds the shaft within the shaft housing or sealing cavity (i.e., when it is mounted annularly around the rotatable shaft in the shaft housing / cavity). Typically, the sealing bushing (i.e., its hollow shape) is characterized by its external dimensions (e.g., outer diameter) being configured to match the internal space of the shaft housing, and its inner diameter being configured to match the size (i.e., diameter) of the rotatable shaft. Of course, the hollow (cylindrical) shape can also be used to match the outer dimensions (diameter) and / or inner diameter of shaft housings and / or shafts with different radial dimensional characteristics.
[0012] The sealing bushing comprises a set or stack of sealing elements, preferably annular sealing elements, configured for detachable assembly with each other to form the sealing bushing. According to the invention, at least one of the sealing elements (hereinafter referred to as the first sealing element) is configured for coupling and securing to another sealing element (hereinafter referred to as the second sealing element) of the sealing bushing via a pin-locking device according to the invention.
[0013] More precisely, the pin locking device according to the invention is configured to lock a first sealing member and a second sealing member together, and includes:
[0014] A pin body, preferably characterized by having a substantially cylindrical shape, including a longitudinal hole extending along the longitudinal axis C of an extension, the longitudinal hole defining a cavity within the pin body, the cavity preferably being centered within the pin body, for example, centered within the cylindrical shape about the longitudinal axis C of the extension (the cavity is particularly cylindrical and extends along the longitudinal axis C of the extension), preferably, the cavity is a blind cavity or extends through the pin body along the longitudinal axis C. According to the invention, the inner wall of the hole includes a fixing structure, the fixing structure including, for example, a thread (in other words, the hole is a threaded hole), the thread being formed, for example, around the inner wall, the fixing structure being configured to cooperate with a removal tool, the removal tool being, for example, a screw having the threaded feature and a diameter substantially equal to the diameter of the threaded hole, the threaded hole being configured to receive the screw. The pin body according to the invention preferably includes two parts arranged longitudinally one after the other along the longitudinal axis C: a first part and a second part. Preferably, when the first portion is projected onto the same plane perpendicular to the longitudinal axis C, the cross-section of the second portion is smaller than that of the first portion and is included within the cross-section of the first portion; both cross-sections are cross sections, i.e., cut perpendicular to the longitudinal axis C. Specifically, according to a first preferred embodiment, the first portion has a cross-section that is the same and constant over its length, which is different from the cross-section of the second portion, and the cross-section of the second portion is also constant and the same over its length, wherein the length is measured along the longitudinal axis C. According to another embodiment, the first and second portions have the same and constant cross-section over the entire longitudinal length of the pin. According to the invention, the first portion is configured to fit a pin cavity of a first sealing member (i.e., the size of the pin cavity matches the size of the first portion of the pin), and the second portion is configured to fit a locking cavity of a second sealing member (i.e., the size of the locking cavity matches the size of the second portion of the pin), wherein if the pin has a constant and identical cross-section over its entire length, the first portion is prevented from entering the locking cavity due to its larger radial dimension compared to the second portion or due to the finite length of the cavity. In the case where the cross-section of the second portion is smaller than that of the first portion (see, for example, see...) Figure 3 and Figure 4) Then the first part, particularly the edge of the first part, is configured to contact a contact surface S3 (hereinafter referred to as the third contact surface) of the second sealing member, the locking cavity being formed in the second sealing member when the second part is adapted to the interior of the locking cavity. According to the invention, the first sealing member and the second sealing member are complementary sealing members configured to be fixed to each other and / or to interlock with each other. For example, the pin body has a cylindrical shape extending along the longitudinal axis C with a nominal radius R1 according to its length L, and at one of its ends includes a flange having a radius R2 (R2 < R1) and a length L2 measured along the longitudinal axis C, such that the first part has a cylindrical shape with a length L - L2 and a radius R1, and the second part includes the flange and thus has a cylindrical shape with a length L2 and a radius R2, the first part and the second part being aligned with each other, the longitudinal axis C passing through the centers of the first part and the second part;
[0015] - A spring, such as a disc spring or a wave spring, is configured to extend and contract (negative extension, i.e., compression) along the longitudinal axis C when placed in the pin cavity. The spring is also configured to apply a spring force to the pin body along the longitudinal axis C, such that the spring force tends to move the pin body in a direction away from the end of the pin cavity. In particular, the spring is configured to bear on one side against a first contact surface of the pin cavity of the first sealing member (the first contact surface corresponding to the end of the pin cavity longitudinally opposite to its opening, the opening and the end being particularly aligned with respect to the longitudinal axis C when the pin body is included in the pin cavity), and to contact with its other side a second contact surface, where the second contact surface is a surface of the pin body, such as an outer surface, on which the hole is formed. The spring, or more precisely its spring force, is configured to move or push the pin body from the retracted position towards the locked position, and to maintain the pin body in the locked position. According to the invention, in the retracted position, the pin body is entirely located within the pin cavity: it corresponds to the compressed state of the spring. In the locked position, the second part of the pin body is received or positioned within the locking cavity and is maintained within the locking cavity by the spring force, while the first part remains located within the pin cavity, so that the pin body bridges the first sealing member and the second sealing member.
[0016] The retaining structure of the hole is configured to mate with the extraction tool to hold the pin in the retracted position during assembly of the first and second sealing components (i.e., holding the pin to press the spring against the end of the pin cavity). In the locked position, the pin prevents radial movement or displacement of the pin cavity relative to the locking cavity (radial movement relative to the longitudinal axis C, i.e., movement perpendicular to the longitudinal axis C), thus maintaining the cavities aligned with each other according to the longitudinal axis C. The complementary geometry of the first and second sealing components prevents longitudinal movement of the first sealing component relative to the second sealing component, for example, the position of one of the first or second sealing components in the pin cavity and / or locking cavity is a sleeve for the other.
[0017] According to the invention, the fixing structure is capable of holding the pin in the retracted position when interacting with the removal tool. Furthermore, and preferably, the interaction between the fixing structure and the removal tool is also configured to gradually compress the spring, for example by rotation of the removal tool about the longitudinal axis C and according to a first rotation direction, and then to hold the pin in the retracted position when assembling the first and second sealing components. The release of this interaction (e.g., by removing the removal tool or by rotating the removal tool in a direction opposite to the first rotation direction) is configured to release the spring, which then pushes the pin to its locked position, resulting in the locking of the first and second sealing components. For example, the removal tool is configured to be insertable into a hole in the first sealing component to interact with the fixing structure of the pin, the hole penetrating the wall of the first sealing component and opening on the first contact surface. Preferably, the spring has a hollow shape, for example, preferably a cylindrical hollow shape about the longitudinal axis C: advantageously, this shape allows the removal tool to pass through the hollow portion to reach the fixing structure of the hole. In other words, the interaction between the removal tool and the pin's fixing structure is configured to hold the pin's fixing structure in the retracted position (where the spring is in a first compressed state) to facilitate the assembly of the first sealing component and the second sealing component, wherein releasing the interaction also releases the spring extending from the first compressed state to the second compressed state, in which the spring holds the pin in the locked position.
[0018] The present invention also relates to a sealing bushing comprising a first sealing member and a second sealing member, wherein the first sealing member includes the pin cavity and the second sealing member includes the locking cavity. Preferably, the first sealing member and the second sealing member are annularly interlocked with each other to prevent radial movement. The pin locking device further prevents relative longitudinal movement of the first sealing member relative to the second sealing member.
[0019] Preferably, the pin cavity and the locking cavity are cylindrical cavities with different diameter characteristics. The pin cavity is characterized by having a radius R1' that matches (i.e. is substantially equal to) the radius R1, such that a first portion of the pin is guided by the wall of the pin cavity (by contacting the wall of the pin cavity) during the movement of the pin from the retracted position to the locked position. The radius R1' is greater than the radius R2' that characterizes the diameter of the locking cavity configured to receive the first portion, wherein the radius R2' is configured to match (i.e. is substantially equal to) the radius R2, such that a second portion of the pin is guided by the wall of the locking cavity (by contacting the wall of the locking cavity) during the movement of the pin from the retracted position to the locked position.
[0020] The pin cavity of the first sealing member is further characterized in that it includes the first contact surface, against which the spring is placed / leaned, or placed / leaned on the first contact surface. Additionally, the first sealing member according to the invention includes a hole drilled through the width of one of its walls, the hole extending from one side of the wall to the other side, on which it opens onto the first contact surface, wherein the hole and the pin cavity extend longitudinally along the longitudinal axis C, such that by inserting the removal tool from one side of the wall until reaching and interacting with the fixing structure on the other side of the wall of the first sealing member, the removal tool can interact with the fixing structure of the pin body's hole. According to the invention, the first sealing member is configured for locking / fixing to a second sealing member by one or more pin locking devices according to the invention. When assembled together, the hole, pin cavity, pin body hole, and locking cavity are preferably aligned with each other, for example, the longitudinal axis C passes through the center of each of the hole, pin cavity, pin body hole, and locking cavity.
[0021] The present invention also relates to a method for assembling a sealing bushing, the method comprising assembling sealing components (preferably annular sealing components) to one another to form the stacked sealing components, and characterized in that the method comprises engaging and locking at least one of the sealing components of the sealing bushing (i.e., the first sealing component) to another of the sealing components (i.e., the second sealing component) by means of a previously described pin locking device. Specifically, the method comprises locking each pin of the first sealing component in a retracted position by interaction of a removal tool with a retaining structure of the hole of each pin, then moving and / or positioning the first sealing component relative to the second sealing component until each pin cavity aligns with a locking cavity of the corresponding second sealing component, and releasing each pin by removing / preventing interaction of the removal tool with the retaining structure, the release of each pin causing the pin to move from the retracted position to a locked position, in which the second portion is adapted and received within the locking cavity of the second sealing component.
[0022] According to the invention and preferably, the first sealing member and / or the second sealing member are each annular sealing members configured to fasten (or fix) each other. The movement of the pin from the retracted position to the locked position can be radial or longitudinal relative to the shaft. In the case of radial movement, and if the first and second sealing members are rotating members (i.e., driven to rotate by the rotation of the shaft), the first sealing member, the second sealing member, and the pin locking device are configured to position the locked position radially further relative to the shaft than the retracted position, such that rotation of the paired first and second sealing members does not cause the pin to shift from the locked position to the retracted position.
[0023] Preferably, the first sealing member and / or the second sealing member are each configured for annular mounting around a shaft, and each is characterized by being configured to match the inner diameter of the shaft, or one of the dimensions (i.e., diameter). Alternatively or additionally, the first sealing member and / or the second sealing member are each configured for annular mounting around a shaft, and each is characterized by being configured to match the outer dimension or outer diameter of the shaft housing, or one of the dimensions. Preferably, the first and second sealing members are configured to remain stationary during rotation of the rotatable shaft. In particular, the first and / or second sealing members may include at least one portion configured to rotate with the rotatable shaft during rotation, and optionally include another portion that remains stationary. In particular, the entire first and / or the entire second sealing member is configured to rotate with the rotatable shaft. Preferably, the first sealing member is a housing member and / or a bushing. Similarly, the second sealing member is a housing member and / or a bushing. For example, a housing member configured to simultaneously form a sleeve around the shaft. Attached Figure Description
[0024] Further description and details of the invention will now be described based on the preferred embodiments shown in the following figures:
[0025] Figure 1 This is a schematic cross-sectional side view of the sealing bushing according to the present invention.
[0026] Figure 2 This is a schematic longitudinal section representing a preferred pin locking device according to the present invention.
[0027] Figure 3 This is a three-dimensional schematic representation of the longitudinal section of another preferred pin locking device according to the present invention.
[0028] Figure 4 This is a three-dimensional view of another preferred pin locking device according to the present invention. Detailed Implementation
[0029] Figure 1 A schematic longitudinal section of the sealing bushing 1 according to the invention is shown. As is known in the art, the sealing bushing 1 may comprise various sealing elements 11-19 stacked according to different configurations and geometries, preferably annular sealing elements. It must be understood that by stacking, the axially centered ("axially centered" is relative to the longitudinal axis of the sealing bushing) assembly of the sealing elements forms a stack or pile of sealing elements that forms the bushing, wherein the sealing elements are preferably axially mounted one after another on top (when the longitudinal axis of the bushing is considered to be vertical) and / or radially mounted around (or covering) previously mounted sealing elements. Figure 1 The purpose is merely to present the concept of the invention, and not to focus on any particular type, configuration, geometry or construction of the sealing bushing.
[0030] according to Figure 1 A sealing bushing 1 is annularly mounted around a rotatable shaft 2, which is configured to rotate about a longitudinal axis of rotation A' according to an angular velocity ω. The sealing bushing 1 is configured to be removably housed within a shaft housing 21, which surrounds and encloses the shaft 2 and the seal provided by the sealing bushing 1. The sealing bushing 1 typically provides a seal between the rotatable shaft 2 and the shaft housing 21, preventing, for example, any leakage or contamination of process gases. Preferably, the sealing bushing according to the invention is a dry gas sealing bushing. The sealing bushing typically has a cylindrical shape centered about a longitudinal axis A, which coincides with the longitudinal axis A' when the sealing bushing is annularly mounted around the shaft 2 in the shaft housing 21.
[0031] According to the invention, at least one, or a portion thereof, or each sealing element 11-19 of the sealing bushing is configured for connection or fastening to at least one other sealing element via a pin-locking device 3 according to the invention. As already described, the sealing elements connected via the pin-locking device 3 are referred to as the first sealing element and the second sealing element, respectively. Although in the present example of the invention the first and second sealing elements are annular sealing elements, it is also conceivable that they could be configured to fit into other hollow shapes within the shaft housing 21. According to the claimed pin-locking device 3, the connection advantageously does not contain any screws and / or bolts securing the first and second sealing elements together.
[0032] like Figure 1As schematically illustrated, a first annular sealing member 11 is connected, for example, to a bushing of a second annular sealing member 12 via a claimed pin-locking device 3, wherein the second annular sealing member 12 is a housing member configured to accommodate one or more sealing elements and radially cover the first annular sealing member 11. Alternatively, a third annular sealing member 13 is connected to a housing member of a fourth annular sealing member 14 via one or more pin-locking devices 3, wherein the fourth annular sealing member 14 is also a housing member configured to accommodate one or more sealing elements. A fifth annular sealing member 15 is connected, for example, to a bushing of one or more annular sealing members via the pin-locking device 3, such as to a third annular sealing member 13 on a radial side of the fifth annular sealing member 15 and / or to a sixth annular sealing member 16 on an axial side of the fifth annular sealing member 15, wherein the sixth annular sealing member 16 is also a bushing. For example, a seventh annular sealing member 17 is connected to a housing member of an eighth annular sealing member 18 via the pin-locking device 3, wherein the eighth annular sealing member 18 is a bushing.
[0033] According to the invention, the first and second sealing components can be any annular (i.e., ring-shaped) sealing component of the sealing bushing, such as a housing, bushing, or ring. Preferably, the first sealing component is the housing component of the sealing bushing, and it is connected to the other component by a pin locking device 3, i.e.:
[0034] - Labyrinth seal for sealing bushing; or
[0035] - Another housing component of the sealing bushing; or
[0036] - Barrier seal of the sealing bushing; or
[0037] - The retaining sleeve of the sealing bushing; or
[0038] - Static sealing ring of the sealing bushing.
[0039] The first sealing component can also be a rotatable sealing bushing, such as a bushing adhered to the shaft and surrounding the engagement ring, the bushing and engagement ring rotating at the same speed as the shaft, wherein the bushing is connected to another component by a pin locking device 3, i.e.:
[0040] - The other bushing of the sealing bushing; or
[0041] - The ring of the sealing bushing, such as a coupling ring; or
[0042] - The sealing bushing is constructed to be used as another component that rotates together with the bushing.
[0043] Figure 2The pin locking device 3 according to the invention is shown in more detail. The pin locking device 3 includes a pin 31 and a spring 32. The pin 31 is configured to interact with a removal tool 4 to press the spring 32 against the end of a pin cavity 100A until the pin 31 reaches a retracted position in which the entire pin 31 is located within the pin cavity 100A. The dimensions of the pin cavity 100A are, of course, configured to receive the spring 32 and the pin 31, for example, the length of the pin cavity is equal to or greater than the length of the spring in its compressed form plus the length of the pin 31, wherein the length is measured along the longitudinal axis C (see...). Figure 2 ).
[0044] To enable it to interact with the extraction tool 4, the pin 31 includes a longitudinal hole 310 extending along the longitudinal axis C. The hole 310 can be as follows: Figure 2 The blind hole shown or as Figure 3 and Figure 4 The preferred embodiment shows a through hole in the through pin 31. The hole 310 includes a fixing structure for interacting with the extraction tool 4. The fixing structure is configured to secure or clamp the pin 31 to a fixing portion of the extraction tool 4, wherein the fixing portion is configured to be inserted into the hole 310 to interact with the fixing structure.
[0045] For example, the fixing structure is a thread arranged in the hole 310, such as on the inner wall 311 of the hole 310, and the removal tool 4 has a screw shape including a head 4A and a cylindrical rod 4B, the cylindrical rod 4B being fixed to the head 4A at one end and including the fixing portion at the other end. Preferably, the extraction tool 4 is configured to be inserted into a hole 101 in the first sealing member 100A, wherein the hole 101 extends longitudinally along a longitudinal axis from one side S' accessible to the operator during bushing assembly to the other side S" of the wall 102 of the first sealing member, the longitudinal axis being aligned with the longitudinal axis of the pin cavity 100A and the pin 31 when the pin 31 is placed into the pin cavity 100A. The hole 101 is formed in the pin cavity 100A, thus penetrating the wall 102, which separates the end of the pin cavity 100A from the head of the extraction tool when the cylindrical rod 4B is inserted into the hole 101. The retaining portion is configured to interact with the retaining structure of the hole 310. In particular, the retaining portion includes complementary threads that are complementary to the threads of the hole 310. In practice, in order to press the spring 32 against the first contact surface S1 corresponding to the end of the pin cavity 100A and the other side S" of the wall 102, the operator can rotate the head 4A about the longitudinal axis C. Due to the rotation, the complementary thread of the fixed part engages with the thread of the hole 310, in other words, the fixed part is screwed into the pin 31, and because the head 4A of the removal tool 4 is configured to be placed against the side S', the screwing causes the pin to be displaced in the direction of the end of the cavity (i.e., in the direction of the first contact surface S1 or S"), the displacement compressing the spring 4 located between the end of the cavity and the second contact surface S2 of the pin 31.
[0046] Preferably, the spring 32 is characterized by a hollow shape, wherein its hollow portion is configured to provide a free passage for the removal tool 4 (e.g., its second portion 4B) from hole 101 toward hole 310, allowing it to interact with pin 31 without contacting the spring 32. The spring 32 is, for example, a disc spring or cylindrical wave spring configured for extension and compression along its length, such as... Figure 3 and Figure 4As shown in the diagram. Preferably, at least a first portion 31A of the pin cavity 100A and the pin body 31 has a cylindrical shape. In this case, the pin cavity 100A and the pin body 31 preferably include complementary structures to prevent the pin body 31 from rotating within the pin cavity 100A during the insertion / extraction of the extraction tool 4 into / out of the hole 311. The complementary structures may be, for example, a groove extending along a direction parallel to the longitudinal axis c on the cylindrical inner wall of the pin cavity and a protruding member extending radially on the outer cylindrical surface of the pin body, or a groove extending along a direction parallel to the longitudinal axis c on the outer cylindrical surface of the pin body and a protruding member extending radially on the cylindrical inner wall of the pin cavity, wherein the groove is configured to receive the protruding member and serves as a guide for the protruding member during longitudinal (i.e., along the longitudinal axis C) displacement of the pin body 31 within the pin cavity caused by insertion or extraction, thus preventing the pin body from rotating within the pin cavity. For example, the pin body may include one or more grooves and / or one or more protruding members, wherein for each groove and each protruding member of the pin body, the pin cavity includes complementary protruding members and grooves, respectively. Of course, those skilled in the art can envision other solutions for preventing rotation of the pin body 31 during screwing in / out: for example, the first portion and the pin cavity may have a non-circular cross-section capable of preventing any rotation about the longitudinal axis C during screwing in / out. In this case, the second portion 31B is preferably cylindrical. Furthermore, the fixing structure may take another form / type, such as a hook and complementary protruding members, or a tenon and mortise system, etc. The purpose of the fixing portion of the removal tool 4 is to cooperate / interact with the fixing structure of the pin body, thereby fixing the pin body 31 to the removal tool such that the removal tool can longitudinally displace the pin body 31 in the pin cavity 100A by compressing the spring 32 to unlock the first and second sealing members, or release the removal tool to longitudinally displace the pin body 31 in the pin cavity 100A to lock the first and second sealing members.
[0047] In practice, when assembling the sealing components of the sealing bushing, it is necessary to connect / lock the first sealing component 10A to the second sealing component 10B. To achieve this connection / locking, the method according to the present invention includes:
[0048] - Lock the pin 31 in the retracted position within the pin cavity 100A. To do this, the operator inserts the removal tool 4 into the hole 101 of the first sealing member, so that its fixing portion can interact with the fixing structure of the pin 31. According to... Figure 2 In the preferred embodiment described in section -4, the fixing part is screwed into the hole 310, thereby locking the fixing part to the pin, wherein the rotation of the head 4A in one direction (the screwing-in direction, which may be clockwise or counterclockwise) is configured to compress the spring, while the rotation in the other direction (the screwing-out direction) is configured to release the spring.
[0049] - Once the pin 31 reaches its retracted position at its end in the pin cavity 100A, the first sealing member can be positioned relative to the second sealing member 10B until the pin cavity 100A is aligned with the locking cavity 100B of the corresponding second sealing member 10B. Depending on the shape of the pin 31, the pin cavity and the locking cavity can have different shapes. For example, if the locking cavity 100B is a blind cavity, including an end that prevents longitudinal movement of the pin 31 when the spring 32 is released, then the pin cavity 100A and the locking cavity 100B can be characterized by having the same cross-section (see...). Figure 2 In this case, the pin 31, as well as the pin cavity and locking cavity, can be cylindrical, with the pin cavity having the same diameter as the locking cavity, and the pin being characterized in that its diameter is close to the diameter of the pin cavity and locking cavity, thereby allowing the pin to slide within the cavity, wherein the wall of the cavity serves as a guide. According to another embodiment, if the locking cavity 100B is a through cavity without an end that prevents longitudinal movement of the pin 31 when the spring 32 is released, then the pin cavity 100A and the locking cavity 100B can be characterized by having different cross-sections (see...). Figure 3 and 4 In this configuration, the pin 31, along with the pin cavity and locking cavity, can be cylindrical, with the pin cavity having a diameter larger than that of the locking cavity. The pin 31 is characterized by having two cylindrical portions: a first cylindrical portion 31A and a second cylindrical portion 31B. The diameter of the first cylindrical portion is close to the diameter of the pin cavity, allowing it to slide within the pin cavity while preventing it from entering the locking cavity. The diameter of the second cylindrical portion is close to the diameter of the locking cavity, allowing it to slide within the locking cavity, wherein the wall of the locking cavity serves as a guide. According to this configuration, when the pin 31 is pushed away from the end of the pin cavity 100a, the surface S3 of the second sealing member 10B prevents longitudinal movement of the pin 31, the second portion remains in the pin cavity, and the first portion is received in the locking cavity.
[0050] - After the pin cavity and locking cavity are aligned, the spring 32 is released by removing the removal tool 4 from the pin body 31, for example by unscrewing the removal tool 4 from the pin body 31. This release causes the pin body 31 to move from the retracted position to the locked position, wherein the first portion 31A of the pin body 31 remains in the pin cavity 100A, while the second portion 31B of the pin body 31 is adapted and received within the locking cavity 100B. At this stage, the first sealing member and the second sealing member are locked together.
[0051] According to the present invention, suitable dimensions are necessary for enabling the first sealing member to lock with the second sealing member. Based on this disclosure, those skilled in the art will be able to determine convenient dimensions for the pin, pin cavity, and locking cavity. As previously stated, the longitudinal dimensions of the pin, pin cavity, locking cavity, and compression spring should conform to the following rules:
[0052] - When the pin is in the retracted position, the longitudinal dimension of the compression spring plus the longitudinal dimension of the pin should be completely included within the longitudinal dimension of the pin cavity;
[0053] - In the locked position, the longitudinal dimension of the pin should allow the first part 31A to be placed in the pin cavity, while the second part is placed in the locking cavity 100B.
[0054] Finally, the spring 32 and the pin 31 can be attached or fixed to each other by a suitable structure, such as screws or welding, or they can be two separate or independent parts that must be inserted one by one by the operator into each pin cavity of the first sealing component and held in the retracted position before the first sealing component is assembled with the second sealing component.
[0055] In summary, the present invention provides a pin locking device 3 for facilitating the assembly of a sealing bushing 1, the sealing bushing 1 comprising one or more sealing components, preferably annular sealing components, configured for ring mounting around a rotatable shaft, wherein at least two of the sealing components are connected / secured to each other by one or more pin locking devices according to the invention. The latter makes the bushing simpler and more compact, enabling quick connection / secured connection / secured sealing components without any screws.
Claims
1. A pin locking device (3) for locking a first sealing member (10A) of a sealing bushing (1) together with a second sealing member (10B) of the sealing bushing (1), the pin locking device (3) comprising: - Pin (31), the pin includes a longitudinal hole (310) extending along the longitudinal axis (C), wherein the inner wall (311) of the hole (310) includes a fixing structure configured to cooperate with the extraction tool (4), the pin (31) includes two parts arranged one after the other along the longitudinal axis (C), namely, a first part (31A) configured to fit into the pin cavity (100A) of the first sealing member (10A) and a second part (31B) configured to fit into the locking cavity (100B) of the second sealing member (10B). - A spring (32) configured to apply a spring force to the pin (31) along the longitudinal axis (C), wherein the spring (32) is configured to rest on a first contact surface (S1) of the pin cavity (100A) on one side and to contact a second contact surface (S2) on the other side, wherein the second contact surface (S2) is the surface of the pin (31) having the hole (310) formed therein, wherein the spring force is configured to move the pin (31) from a retracted position toward a locked position, wherein in the retracted position the pin (31) is fully located within the pin cavity (100A), and in the locked position the second portion (31B) is located and held within the locked cavity (100B), while the first portion (31A) remains located within the pin cavity (100A).
2. The pin locking device (3) according to claim 1, wherein, The fixing structure is configured to interact with the removal tool (4) during the assembly of the first sealing member (10A) and the second sealing member (10B) to compress the spring (32) and hold the pin (31) in the retracted position, and the spring (32) is configured to move the pin (31) from the retracted position to the locked position when the interaction is released.
3. The pin locking device (3) according to claim 1 or 2, wherein, When the first portion (31A) is projected onto the same plane perpendicular to the longitudinal axis (C), the cross-section of the second portion (31B) is smaller than the cross-section of the first portion (31A) and is included within the cross-section of the first portion (31A).
4. The pin locking device (3) according to claim 1 or 2, wherein, The fixing structure is a thread formed around the inner wall (311).
5. The pin locking device (3) according to claim 1 or 2, wherein, The first part (31A) and the second part (31B) are cylindrical.
6. A sealing bushing (1) configured to provide a seal between a rotatable shaft (2) and a shaft housing (21), the sealing bushing (1) having a hollow shape around a longitudinal axis (A), the sealing bushing (1) comprising: A set of sealing components configured to be removably assembled with each other to form the sealing bushing (1), wherein each of the sealing components is configured to be mounted in an annular shape around the rotatable shaft (2); The sealing bushing (1) is characterized in that at least one of the sealing components, hereinafter referred to as the first sealing component (10A), is configured to be fastened or secured to another of the sealing components, hereinafter referred to as the second sealing component (10B), by means of a pin locking device (3) according to any one of claims 1 to 5, wherein the first sealing component (10A) includes the pin cavity (100A) and the second sealing component (10B) includes the locking cavity (100B).
7. The sealing bushing (1) according to claim 6, wherein, The first sealing member (10A) includes a hole (101) through a wall (102) of the first sealing member (10A), the hole (101) extending from one side (S') of the wall (102) to the other side (S'') of the wall (102), on the other side (S''), the hole (101) is opened on the first contact surface (S1), wherein the hole (101), the pin cavity (100A), the hole (310) of the pin body (31) and the locking cavity (100B) are configured to align with each other when the first sealing member (10A) and the second sealing member (10B) are assembled.
8. The sealing bushing (1) according to claim 6 or 7, wherein, The hollow shape is a substantially cylindrical hollow shape around the longitudinal axis (A), and the sealing component of the assembly is an annular sealing component.
9. The sealing bushing (1) according to claim 6 or 7, wherein, The first sealing member (10A) is characterized in that it is configured to match the inner diameter of the shaft (2), and the first sealing member (10A) is a bushing (11).
10. The sealing bushing (1) according to claim 6 or 7, wherein, The first sealing component (10A) is characterized in that it is configured to match the external dimensions or outer diameter of the shaft housing (21), the first sealing component (10A) being a housing component (12).
11. The sealing bushing (1) according to claim 6 or 7, wherein, The first sealing member (10A) is configured to remain stationary during rotation of the rotatable shaft (2).
12. The sealing bushing (1) according to claim 6 or 7, wherein, The first sealing member (10A) includes at least one portion configured to rotate together with the rotatable shaft (2) during rotation.
13. The sealing bushing (1) according to claim 6 or 7, wherein, The first sealing component (10A) is the housing component of the sealing bushing (1), and the second sealing component (10B) is: a. The labyrinth seal of the sealing bushing; or b. Another housing component of the sealing bushing; or c. The barrier seal of the sealing bushing; or d. The retaining sleeve of the sealing bushing; or e. The static sealing ring of the sealing bushing.
14. The sealing bushing (1) according to claim 6 or 7, wherein, The first sealing component (10A) is a rotatable bushing of the sealing bushing (1), and the second sealing component (10B) is: a. The other bushing of the sealing bushing; or b. The rotatable sealing ring of the sealing bushing; or c. The sealing bushing is configured to rotate together with another component of the rotatable bushing.
15. A method for assembling a sealing bushing (1) configured to provide a seal between a rotatable shaft (2) and a shaft housing (21), the sealing bushing (1) having a hollow shape around a longitudinal axis (A) and comprising stacked sealing components, the method comprising: - Assemble the sealing components together to form the stacked sealing components; The method is characterized in that it includes engaging and locking at least one of the sealing components of the sealing bushing (1), referred to as the first sealing component (10A), to another of the sealing components, referred to as the second sealing component (10B), by means of the pin locking device (3) according to any one of claims 1 to 5, wherein the engagement and locking includes: - Lock the pin (31) of the pin locking device (3) into the retracted position within the pin cavity (100A) of the first sealing member (10A). - Position the first sealing member (10A) relative to the second sealing member (10B) until the pin cavity (100A) is aligned with the locking cavity (100B) of the corresponding second sealing member (10B). - Release the pin (31), wherein the release causes the pin (31) to move from the retracted position to the locked position, in which the first portion (31A) of the pin (31) is held in the pin cavity (100A), while the second portion (31B) of the pin (31) is adapted and received in the locking cavity (100B).