Shaft end combined sealing structure of massecuite distribution tank stirring shaft

Abstract

The utility model provides a shaft end combined sealing structure of a massecuite distribution tank stirring shaft, which is characterized in that the stirring shaft transversely extends out through a central hole of a flange end plate, and the flange end plate is fixedly connected with a filler seat; a right barrel opening of the barrel seat of the filler seat is provided with a blocking edge; the left side of the blocking edge is a filler cavity; the right end head of the cylinder seat extends into a central hole of the flange end plate; an inner hole of the blocking edge is provided with an air cavity and a plurality of annular narrow grooves, and a first-stage labyrinth sealing structure is formed between the annular narrow grooves and the stirring shaft; the stirring shaft is fixedly sleeved with a movable ring on the right side of the filler seat, the left end of the movable ring extends into a center hole of the flange end plate, an air gap channel is reserved between the movable ring and the filler seat, and a second-stage labyrinth sealing structure is formed between an external thread groove of the movable ring and the center hole of the flange end plate; and a packing ring is filled in a packing cavity of the packing seat and is provided with a packing gland for pressing. The shaft end combined sealing structure can effectively avoid denaturation and failure caused by direct contact of massecuite and the filler ring, so that the durability of shaft end sealing is improved, and the problem that massecuite leaks from a sealing gap can be avoided.

Description

Technical Field

[0001] The utility model relates to a shaft end sealing structure, in particular to a shaft end combined sealing structure of a stirring shaft of a sugar paste distribution tank, belonging to the technical field of sealing components of stirring and conveying equipment in a sugar factory. Background Art

[0002] The sugar paste distribution tank is a device used for stirring and conveying sugar paste in the sugar refining workshop. When working, it is filled with a large amount of sugar paste and is equipped with a low-speed stirring shaft to stir and convey the sugar paste. The stirring shaft of the sugar paste distribution tank works at a speed of about 10rpm. The shaft end seals at the inner and outer connections of the stirring shaft generally use packing seals, and a packing gland is provided to compress the packing. Under the ordinary packing seal structure, the sugar paste in the sugar paste distribution tank will penetrate into the gap and directly soak into the sealing packing at the end of the stirring shaft. The sealing packing after soaking in sugar paste is easy to harden and lose elasticity, so the sugar paste often leaks out from the sealing gap at the end of the stirring shaft. After the leakage occurs, the sealing packing has been denatured at this time, and it is difficult to enhance the sealing effect even if the packing gland is further tightened. If the sugar paste leaks too much, the machine can only be shut down to replace the new sealing packing, which has a great impact on the continuity of production.

[0003] In order to completely solve the problem of sugar mass leakage caused by failure of the shaft end seal of the stirring shaft in the sugar mass distribution tank, we have specially improved the shaft end seal structure of the stirring shaft. Utility Model Content

[0004] The utility model aims to provide a shaft end combined sealing structure of a stirring shaft of a massecuite distributing tank, so as to solve the problem that the shaft end sealing of the stirring shaft of the existing massecuite distributing tank is easy to fail and cause massecuite leakage.

[0005] The specific technical solutions adopted by this utility model are as follows:

[0006] A shaft end combined sealing structure for a stirring shaft of a sugar paste distribution trough, wherein a vertically arranged flange end plate is provided on the outer shell of the sugar paste distribution trough, and the shaft end of the stirring shaft extends horizontally from the inside of the sugar paste distribution trough on the right side of the flange end plate through the center hole of the flange end plate to the outside of the sugar paste distribution trough on the left side of the flange end plate, and a packing seat is fixedly connected to the left end face of the flange end plate.

[0007] The center of the packing seat is a cylindrical cylinder seat which is laterally sleeved on the periphery of the stirring shaft. The right barrel mouth of the cylinder seat is provided with a radially inward annular retaining edge, and the inner hole of the retaining edge forms a clearance fit with the stirring shaft. The cavity between the inner hole of the cylinder seat on the left side of the retaining edge and the stirring shaft is the packing cavity; the circumferential outer wall of the cylinder seat is provided with a circle of radially outward-expanding cylinder seat flange at a position close to the right barrel mouth, and the right end of the cylinder seat on the right side of the cylinder seat flange matches the central hole of the flange end plate, and the cylinder seat flange is fixedly connected to the left end face of the flange end plate by screws, and at the same time, the right end of the cylinder seat extends from left to right into the central hole of the flange end plate for a distance; the inner hole of the retaining edge is provided with a circle of annular wide grooves as an air cavity at a position corresponding to the cylinder seat flange, and the air cavity is provided with a radially outward-expanding air inlet channel connected to the external air nozzle on the circumferential side wall of the cylinder seat flange, and the inner hole of the retaining edge is provided with a plurality of annular narrow grooves on the right side of the air cavity, and the tortuous channel between the annular narrow groove of the inner hole of the retaining edge and the stirring shaft constitutes a first-level labyrinth sealing structure connected to the air cavity.

[0008] A moving ring which rotates synchronously with the stirring shaft is fixedly mounted on the right side of the packing seat on the shaft body of the stirring shaft, and the left end of the moving ring extends from right to left into the center hole of the flange end plate for a distance and forms a clearance fit with the center hole of the flange end plate. A gap is left between the left end face of the moving ring and the right end face of the cylinder seat of the packing seat as an air gap channel, and an external thread groove is provided on the outer circumference of the part of the moving ring extending into the center hole of the flange end plate. The thread rotation direction of the external thread groove is opposite to the rotation direction of the stirring shaft, and the tortuous channel between the external thread groove of the moving ring and the center hole of the flange end plate constitutes a second-level labyrinth sealing structure; at the same time, the Z-shaped stepped channel formed by connecting the channel of the first-level labyrinth sealing structure, the air gap channel and the channel of the second-level labyrinth sealing structure in the longitudinal section also constitutes a labyrinth sealing structure.

[0009] The packing cavity of the packing seat is filled with multiple layers of packing rings. A packing gland is mounted on the shaft body of the stirring shaft in the left gap of the packing seat. The packing gland is provided with a radially outward-extending cover edge and a top ring extending to the left. The packing gland is fixedly connected to the left end face of the packing seat by a clamping bolt passing through the cover edge. At the same time, the top ring of the packing gland extends into the packing cavity of the packing seat to compress the packing ring.

[0010] The shaft end combined sealing structure of the utility model is provided with a two-stage stepped labyrinth sealing structure in the area near the sugar paste, and a packing sealing structure is adopted in the outer area. An air cavity is arranged between the labyrinth sealing structure of the packing seat and the packing sealing structure. When in use, after the compressed air connected from the external air nozzle enters the air cavity, most of it flows to the stepped channel composed of the two-stage labyrinth sealing structure, thereby forming a higher airflow between the gaps of the stepped channel. When the moving ring rotates with the stirring shaft, the external thread groove of the moving ring continuously pushes most of the sugar paste flowing to the gap of the second-stage labyrinth sealing structure into the sugar paste distribution groove, so that it is away from the labyrinth sealing gap. A small amount of sugar paste entering the labyrinth sealing gap cannot enter the packing sealing structure against the airflow and contact the packing ring under the obstruction of the airflow. Therefore, by adopting multiple sealing structures for organic combination, the shaft end combined sealing structure can effectively avoid the sugar paste from directly contacting the packing ring of the packing cavity, resulting in its degeneration and failure, thereby increasing the durability of the shaft end seal and avoiding the problem of sugar paste leaking from the sealing gap, and maintaining the continuity of production. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a cross-sectional view of the shaft end combined sealing structure.

[0012] Figure 2 for Figure 1 A partial enlarged view of .

[0013] Figure 3 A cross-sectional view of the packing seat.

[0014] Figure 4 This is a cross-sectional view of the moving ring.

[0015] In the figure: 1-flange end plate, 2-agitation shaft, 3-packing seat, 3.1-cylinder seat, 3.2-blocking edge, 3.3-packing cavity, 3.4-cylinder seat flange, 3.5-air cavity, 3.6-air inlet channel, 3.7-external air nozzle, 3.8-annular narrow groove, 4-screw, 5-moving ring, 5.1-external thread groove, 5.2-locking screw, 6-packing ring, 7-packing gland, 8-clamping bolt. DETAILED DESCRIPTION

[0016] The present invention is further described below in conjunction with the embodiments and drawings. In the description of the present invention, the directional words "front", "back", "left", "right", "up", and "down" are based on the attached description. Figure 1 The orientation or position relationship shown is only defined to facilitate the description of the present invention, rather than referring to a specific orientation that a device or element must have, and should not be regarded as a limitation to the present invention.

[0017] like Figure 1-4As shown, the shaft end combined sealing structure of the stirring shaft of the sugar paste distribution tank is provided with a vertically arranged flange end plate 1 on the outer shell of the sugar paste distribution tank, and the shaft end of the stirring shaft 2 extends horizontally from the inside of the sugar paste distribution tank on the right side of the flange end plate 1 through the center hole of the flange end plate 1 to the outside of the sugar paste distribution tank on the left side of the flange end plate 1, and the left end face of the flange end plate 1 is fixedly connected to a packing seat 3.

[0018] The center of the packing seat 3 is a cylindrical barrel seat 3.1 which is laterally sleeved on the outer periphery of the stirring shaft 2. The right barrel mouth of the barrel seat 3.1 is provided with a radially inward-contracted annular retaining edge 3.2. The inner hole of the retaining edge 3.2 forms a clearance fit with the stirring shaft 2. The cavity between the inner hole of the barrel seat 3.1 on the left side of the retaining edge 3.2 and the stirring shaft 2 is the packing cavity 3.3. The circumferential outer wall of the barrel seat 3.1 is provided with a circle of radially outward-contracted barrel seat flange 3.4 near the right barrel mouth. The right end of the barrel seat 3.1 on the right side of the barrel seat flange 3.4 matches the center hole of the flange end plate 1. The barrel seat flange 3.4 is fixedly connected to the flange by screws 4. On the left end surface of the end plate 1, the right end of the cylinder seat 3.1 extends from left to right into the center hole of the flange end plate 1 for a distance; the inner hole of the retaining edge 3.2 is provided with a circle of wide annular grooves as an air cavity 3.5 at a position corresponding to the cylinder seat flange 3.4, and the air cavity 3.5 is provided with a radially outward air inlet channel 3.6 connected to the external air nozzle 3.7 on the circumferential side wall of the cylinder seat flange 3.4, and the inner hole of the retaining edge 3.2 is provided with a plurality of annular narrow grooves 3.8 on the right side of the air cavity 3.5, and the tortuous channel between the annular narrow grooves 3.8 of the inner hole of the retaining edge 3.2 and the stirring shaft 2 constitutes a first-level labyrinth sealing structure connected to the air cavity 3.5.

[0019] A moving ring 5 which rotates synchronously with the stirring shaft 2 is fixedly sleeved on the right side of the packing seat 3 on the shaft body of the stirring shaft 2. The left end of the moving ring 5 extends from right to left into the center hole of the flange end plate 1 for a distance and forms a clearance fit with the center hole of the flange end plate 1. A gap is left between the left end face of the moving ring 5 and the right end face of the cylinder seat 3.1 of the packing seat 3 as an air gap channel. An external thread groove 5.1 is provided on the outer circumference of the part of the moving ring 5 extending into the center hole of the flange end plate 1. The thread rotation direction of the external thread groove 5.1 is opposite to the rotation direction of the stirring shaft 2. The tortuous channel between the external thread groove 5.1 of the moving ring 5 and the center hole of the flange end plate 1 constitutes a second-level labyrinth sealing structure; at the same time, the Z-shaped stepped channel formed by connecting the channel of the first-level labyrinth sealing structure, the air gap channel and the channel of the second-level labyrinth sealing structure in the longitudinal section also constitutes a labyrinth sealing structure.

[0020] The packing cavity 3.3 of the packing seat 3 is filled with multiple layers of packing rings 6. A packing gland 7 is mounted on the shaft body of the stirring shaft 2 in the left gap of the packing seat 3. The packing gland 7 is provided with a radially outwardly extending cover edge and a top ring extending to the left. The packing gland 7 is fixedly connected to the left end face of the packing seat 3 by a clamping bolt 8 passing through the cover edge. At the same time, the top ring of the packing gland 7 extends into the packing cavity 3.3 of the packing seat 3 to clamp the packing ring 6.

[0021] Furthermore, the moving ring 5 is fixedly connected to the shaft body of the stirring shaft 2 by means of locking screws 5.2 extending radially therein.

[0022] Furthermore, the air cavity 3.5 of the packing seat 3 is provided with two air inlet passages 3.6, and the two air inlet passages 3.6 are respectively connected to two external air nozzles 3.7 on the circumferential side wall of the cylinder seat flange 3.4 to ensure sufficient air intake.

[0023] Furthermore, the number of layers of the packing rings 6 filled in the packing cavity 3.3 of the packing seat 3 is more than 3, and the packing rings 6 are packing packing sealing rings.

[0024] The working principle of this shaft end combined seal structure is as follows:

[0025] The shaft end combined sealing structure is provided with a two-stage stepped labyrinth sealing structure in the area near the sugar paste, and a packing sealing structure is used in the outer area. The labyrinth sealing structure is generally applied to high-speed shafts to produce airflow sealing effects. For the stirring shaft of the sugar paste distribution tank with a low speed, it is necessary to introduce compressed air to force airflow through the gap of the labyrinth seal to achieve a better sealing effect. Therefore, the shaft end combined sealing structure is provided with an air cavity between the labyrinth sealing structure of the packing seat and the packing sealing structure. When in use, compressed air is connected from an external air nozzle. After the compressed air enters the air cavity, it is blocked by the packing sealing structure (the packing sealing structure here mainly serves the purpose of blocking compressed air and preventing excessive leakage of compressed air). Most of it flows to the stepped channel composed of the two-stage labyrinth sealing structure and enters the sugar paste distribution tank, thereby forming a higher airflow between the gaps of the stepped channel. When the moving ring rotates with the stirring shaft, the external thread groove of the moving ring continuously pushes most of the sugar paste flowing into the gap of the second-stage labyrinth sealing structure into the sugar paste distribution groove like a screw conveyor, so as to keep it away from the labyrinth sealing gap. A small amount of sugar paste entering the labyrinth sealing gap cannot go against the airflow to the packing sealing structure and contact the packing ring due to the obstruction of the airflow, thereby avoiding the problem of direct contact between the sugar paste and the packing ring, resulting in its denaturation and failure and causing sugar paste leakage.

[0026] The above-mentioned figures are only typical embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A shaft end combined sealing structure for a stirring shaft of a massecuite dispensing tank, characterized by: The shaft end combined sealing structure is provided with a flange end plate (1) arranged vertically on the outer shell of the massecuite distribution groove, the shaft end of the stirring shaft (2) extends horizontally from the inside of the massecuite distribution groove on the right side of the flange end plate (1) through the central hole of the flange end plate (1) to the outside of the massecuite distribution groove on the left side of the flange end plate (1), and the left end surface of the flange end plate (1) is fixedly connected with a packing seat (3); The center of the packing seat (3) is a cylindrical barrel seat (3.1) which is laterally mounted on the outer periphery of the stirring shaft (2). The right barrel mouth of the barrel seat (3.1) is provided with a radially inwardly contracted annular retaining edge (3.2). The inner hole of the retaining edge (3.2) forms a clearance fit with the stirring shaft (2). The cavity between the inner hole of the barrel seat (3.1) on the left side of the retaining edge (3.2) and the stirring shaft (2) is the packing cavity (3.3). The circumferential outer wall of the barrel seat (3.1) is provided with a circle of radially outwardly extending barrel seat flange (3.4) near the right barrel mouth. The right end of the barrel seat (3.1) matches the center hole of the flange end plate (1) at the right side of the barrel seat flange (3.4). The barrel seat flange (3.4) is fixedly connected to the flange by screws (4). On the left end surface of the flange end plate (1), the right end of the cylinder seat (3.1) extends from left to right into the center hole of the flange end plate (1) for a distance; the inner hole of the retaining edge (3.2) is provided with a circle of wide annular grooves as an air cavity (3.5) at a position corresponding to the cylinder seat flange (3.4); the air cavity (3.5) is provided with a radially outward air inlet channel (3.6) connected to an external air nozzle (3.7) on the circumferential side wall of the cylinder seat flange (3.4); the inner hole of the retaining edge (3.2) is provided with a plurality of narrow annular grooves (3.8) on the right side of the air cavity (3.5); the tortuous channel between the narrow annular grooves (3.8) of the inner hole of the retaining edge (3.2) and the stirring shaft (2) constitutes a first-level labyrinth seal structure connected to the air cavity (3.5); A moving ring (5) is fixedly sleeved on the right side of the packing seat (3) on the shaft body of the stirring shaft (2) and rotates synchronously with the stirring shaft (2). The left end of the moving ring (5) extends from right to left into the center hole of the flange end plate (1) for a distance and forms a clearance fit with the center hole of the flange end plate (1). A gap is left between the left end face of the moving ring (5) and the right end face of the cylinder seat (3.1) of the packing seat (3) as an air gap channel. An external thread groove (5.1) is provided on the outer circumference of the portion of the moving ring (5) extending into the center hole of the flange end plate (1). The thread rotation direction of the external thread groove (5.1) is opposite to the rotation direction of the stirring shaft (2). The tortuous channel between the external thread groove (5.1) of the moving ring (5) and the center hole of the flange end plate (1) constitutes a second-level labyrinth seal structure; at the same time, the Z-shaped stepped channel formed by connecting the channel of the first-level labyrinth seal structure, the air gap channel and the channel of the second-level labyrinth seal structure in the longitudinal section also constitutes a labyrinth seal structure. A packing cavity (3.3) of the packing seat (3) is filled with multiple layers of packing rings (6). A packing gland (7) is sleeved on the shaft body of the stirring shaft (2) in the left gap of the packing seat (3). The packing gland (7) is provided with a radially outwardly extending cover edge and a top ring extending to the left. The packing gland (7) is fixedly connected to the left end surface of the packing seat (3) by a clamping bolt (8) passing through the cover edge. At the same time, the top ring of the packing gland (7) extends into the packing cavity (3.3) of the packing seat (3) to clamp the packing ring (6).

2. The shaft end combined sealing structure of the stirring shaft of the massecuite dispensing tank according to claim 1 is characterized by: The moving ring (5) is fixedly connected to the shaft body of the stirring shaft (2) by means of locking screws (5.2) extending radially therein.

3. The shaft end combined sealing structure of the stirring shaft of the massecuite dispensing tank according to claim 2 is characterized by: The air cavity (3.5) of the packing seat (3) is provided with two air inlet passages (3.6), and the two air inlet passages (3.6) are respectively connected to two external air nozzles (3.7) on the circumferential side wall of the cylinder seat flange (3.4).

4. The shaft end combined sealing structure of the stirring shaft of the massecuite dispensing tank according to claim 1 is characterized by: The number of layers of packing rings (6) filled in the packing cavity (3.3) of the packing seat (3) is more than 3, and the packing rings (6) are packing packing sealing rings.

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