Screw sealing structure and bulking machine

Abstract

The utility model belongs to the technical field of bulking machine rotor assemblies. The screw sealing structure comprises a main shaft; the screw rod is arranged on the main shaft, the screw rod comprises a plurality of screw rod sections, a labyrinth type sealing structure is arranged between the corresponding end faces of the adjacent screw rod sections, and the labyrinth type sealing structure comprises an end face sealing structure and a gap sealing structure which are arranged from outside to inside; the end face sealing structure is formed by attaching the opposite outer end faces of the adjacent screw sections. The gap sealing structure comprises sealing installation holes and bosses which are arranged at the corresponding ends of the adjacent screw rod sections and matched with each other, and the bosses are arranged in the sealing installation holes to form the gap sealing structure of the adjacent screw rod sections. The screw element is used for solving the technical problems that the end face of the screw element of the existing bulking machine is not tight in sealing, materials are extruded to a spline where an inner cavity of the screw is matched with a main shaft in the production process, and the materials are carbonized after being subjected to high temperature, so that the screw is difficult to disassemble. The utility model further discloses a bulking machine which comprises the screw sealing structure.

Description

Technical Field

[0001] The utility model belongs to the technical field of the rotor assembly of an extruder, and particularly relates to a screw sealing structure and an extruder including the above screw sealing structure. Background Art

[0002] An extruder is a commonly used device in the process of processing granular feed. The rotor assembly is used to discharge the preliminarily cooked powder after tempering through the screw extrusion and conveying process, which generates mixing, stirring, kneading, shearing and other effects, and is discharged from the discharge device of the extruder. At the same time of discharging, it is cut by a cutting device to form granular materials.

[0003] In the prior art, the rotor assembly is generally assembled by superposing and combining a main shaft and several screws. The superposition and combination between the screws rely on the end plane of the screw for sealing. The sealing effect of the end face depends on relevant factors such as the machining quality of the end face, the use environment and the assembly quality. In actual use, the sealing effect is not good. During the production process, some materials in the extruder are in a molten state of high temperature, high pressure and high humidity, showing the characteristics of a fluid. During the screw extrusion and conveying process, the material easily penetrates into the inner cavity of the screw through the sealing end face of the screw. After long-term high temperature, the material will be carbonized. The carbonized material will adhere to the spline where the screw and the main shaft are matched, making it very difficult to disassemble the screw when replacing the screw configuration or performing maintenance. It is not only time-consuming and laborious, but sometimes it can only be disassembled destructively, which will cause an extension of the downtime and certain economic losses.

[0004] Therefore, improving the sealing performance of the screw in the rotor assembly has become an urgent problem to be solved. Summary of the Utility Model

[0005] The first object of the utility model is to provide a screw sealing structure to solve the technical problem that the end face sealing of the screw element of the existing extruder is not tight, and during the production process, the material is extruded onto the spline where the screw inner cavity and the main shaft are matched, and the material is carbonized after high temperature, resulting in difficult disassembly of the screw.

[0006] To solve the above technical problem, the utility model adopts the following technical solutions. The screw sealing structure is characterized by including:

[0007] A main shaft;

[0008] A screw arranged on the main shaft, the screw includes several screw segments, and a labyrinth seal structure is arranged between the corresponding end faces of adjacent screw segments, including an end face seal structure and a clearance seal structure arranged from outside to inside;

[0009] The end face seal structure is formed by the relative outer end faces of adjacent screw segments being fitted together;

[0010] The gap sealing structure comprises matching sealing installation holes and bosses arranged at corresponding ends of adjacent screw segments, wherein the bosses are arranged in the sealing installation holes to form a gap sealing structure of adjacent screw segments.

[0011] The utility model designs a combined sealing structure, in which a sealing structure with a small gap fit is arranged on the inner side of the end plane sealing structure of the screw to form a labyrinth sealing structure, thereby improving the sealing effect of the screw in the rotor assembly and preventing the material from being squeezed into the inner cavity of the screw, effectively solving the problem that the screw of the extruder is difficult or even impossible to disassemble, reducing the labor intensity during maintenance and lowering the production cost.

[0012] In order to solve the technical problem of how to connect the main shaft with the spline, the utility model adopts the following technical solution: the main shaft and the screw are spline-connected.

[0013] In order to solve the technical problem of how to match the boss with the sealing mounting hole, the utility model adopts the following technical solution: the longitudinal section of the boss is square, the outer end surface of the inner spline of the screw segment is inclined upward, and a gap is left between the inner wall of the boss and the upper edge of the outer end surface of the inner spline of the screw segment.

[0014] The inner wall of the boss and the end face of the screw inner cavity spline are staggered by a certain distance, the diameter of the screw end face boss matches the diameter of the screw end face seal mounting hole, the length of the screw end face boss matches the depth of the screw end face countersunk hole, and several screws are stacked and sleeved on the main shaft in sequence to form a rotor assembly, and the boss on the end face of one screw is nested in the seal mounting hole on the end face of another screw.

[0015] In order to solve the technical problem of how the boss and the sealing mounting hole cooperate, the utility model adopts the following technical solution: the longitudinal section of the boss is a right-angled trapezoid, and the oblique waist of the right-angled trapezoid is the inner wall of the boss; the outer end surface of the inner spline of the screw segment is inclined upward; the inner wall of the boss and the outer end surface of the inner spline of the screw segment are overlapped.

[0016] In order to further solve the technical problem of sealing the end faces of adjacent screw segments, the utility model adopts the following technical solution: a first seal is arranged on the contact surface between the boss and the seal mounting hole. The utility model forms a combined sealing structure of end face sealing, small gap sealing and first seal sealing, with an additional first seal sealing, and the combination of multiple seals achieves a better sealing effect.

[0017] In order to solve the technical problem of how to install the first seal, the utility model adopts the following technical solution: a first seal installation groove is arranged on the outer circumferential surface of the boss, and the first seal is arranged on the first seal installation groove.

[0018] To further solve the technical problem of end face sealing of adjacent screw segments, the present utility model adopts the following technical solution, and a second seal is provided on the relative outer end faces of the adjacent screw segments. The present utility model forms a combined seal structure of end face seal + small clearance seal + first seal + second seal. With the addition of the second seal, the combination of multiple seals achieves a better sealing effect.

[0019] The second object of the present utility model is to provide an extruder, including the screw seal structure described in any one of the above. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is the front view structural schematic diagram of the present utility model;

[0021] Figure 2 is the front view sectional structural schematic diagram of Embodiment 1 of the present utility model;

[0022] Figure 3 is Figure 1 the partial enlarged structural schematic diagram of A in

[0023] Figure 4 is the front view sectional structural schematic diagram of Embodiment 2 of the present utility model;

[0024] Figure 5 is Figure 4 the partial enlarged structural schematic diagram of B in

[0025] Figure 6 is the front view sectional structural schematic diagram of Embodiment 3 of the present utility model;

[0026] Figure 7 is Figure 6 the partial enlarged structural schematic diagram of C in

[0027] Figure 8 is the structural schematic diagram of the second seal of the present utility model;

[0028] In the figure:

[0029] 10 Screw seal structure;

[0030] 100 Main shaft; 101 External spline;

[0031] 200 Screw; 210 First screw; 211 First internal spline; 212 Seal installation hole; 213 Outer end face; 214 Second seal installation groove; 220 Second screw; 221 Second internal spline; 222 Boss; 2220 First seal installation groove; 223 Outer end face;

[0032] 310 First seal; 320 Second seal. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] Example 1

[0034] like Figures 1-3 As shown, the screw sealing structure 10 includes a main shaft 100 and a screw 200 .

[0035] An external spline 101 is machined on the spindle 100 .

[0036] The screw rod 200 is mounted on the main shaft 100. Specifically, the main shaft 100 and the screw rod 200 are spline-connected.

[0037] The screw 200 includes a plurality of screw segments, and a labyrinth seal structure is arranged between corresponding end faces of adjacent screw segments. The labyrinth seal structure includes an end face seal structure and a gap seal structure arranged from outside to inside. The end face seal structure is formed by the relative outer end faces of adjacent screw segments being fitted together. The gap seal structure includes matching seal mounting holes and bosses arranged at corresponding ends of adjacent screw segments, and the bosses are arranged in the seal mounting holes to form a gap seal structure of adjacent screw segments.

[0038] Specifically, the screw segment 200 includes a first screw segment 210 and a second screw segment 220 which are adjacently arranged.

[0039] The inner cavity of the first screw segment 210 is processed with a first internal spline 211. A sealing installation hole 211 is arranged on the corresponding end surface of the first screw segment, and the sealing installation hole 212 is a countersunk hole and is arranged axially.

[0040] The inner cavity of the second screw segment 220 is processed with a second internal spline 221. The outer end surface of the second internal spline 221 is inclined upward. A boss 222 is arranged on the end surface of the second screw segment 220 corresponding to the first screw segment 110, and the boss 222 is arranged axially. The boss 222 is matched with the sealing mounting hole 2212.

[0041] The longitudinal section of the boss 222 is square, and a gap is left between the inner side wall of the boss 222 and the upper edge of the outer end surface of the second inner spline 221 .

[0042] The screw sealing structure of the utility model comprises a main shaft and a screw. The screw is usually sleeved on the main shaft through a spline connection. A countersunk hole is provided on the end plane of one side of the screw, and a boss is provided on the end plane of the other side of the screw. The inner side wall of the boss and the end face of the spline of the inner cavity of the screw are staggered by a certain distance. The diameter of the boss on the end face of the screw matches the diameter of the countersunk hole on the end face of the screw, and the length of the boss on the end face of the screw matches the depth of the countersunk hole on the end face of the screw. Several screws are stacked and sleeved on the main shaft in sequence to form a rotor assembly. The boss on the end face of one side of the screw is nested in the countersunk hole on the end face of one side of the other screw. At the same time, the end planes of the two screws will also fit together, thereby forming a labyrinth sealing structure of end face sealing and small gap sealing.

[0043] Example 2

[0044] As Figures 4-5 shown, in this embodiment, the longitudinal section of the boss 222 is a right trapezoid, and the oblique waist of the right trapezoid is the inner side wall of the boss. The inner side wall of the boss 222 coincides with the outer end face of the second internal spline 221.

[0045] In this embodiment, the end face of the boss on one side of the screw coincides with the end face of the internal spline in the screw cavity on that side. When the screws are stacked and sleeved in sequence, the width dimension of the sealing surface is increased, that is, the size of the sealing surface is appropriately extended on the basis of the structure of Embodiment 1, which is beneficial to achieving a better sealing effect.

[0046] Embodiment 3

[0047] As Figures 6-7 shown, a first seal 310 is provided on the contact surface between the boss 222 and the seal mounting hole 212.

[0048] In one embodiment, a first seal mounting groove 2220 is provided on the outer circumferential surface of the boss 222. Specifically, the first seal mounting groove 2220 is an annular groove. The first seal 310 is installed in the first seal mounting groove 2220. The first seal 310 is preferably an O-ring.

[0049] In this embodiment, the outer circumferential surface of the end face boss on one side of the screw is provided with a first seal mounting groove, and a first seal is provided in the first seal mounting groove. After a plurality of screws are stacked and sleeved on the main shaft in sequence, there is an additional first seal on the basis of the structure of Embodiment 2, that is, a combined seal structure of end face seal + small clearance seal + first seal is formed, and the combination of multiple seals achieves a better sealing effect.

[0050] Embodiment 4

[0051] As Figure 8 shown, a second seal 320 is provided between the outer end face 213 of the first screw section 210 and the outer end face 223 of the second screw rod 220. Specifically, as Figure 8 shown, a second seal mounting groove 214 is provided on the outer end face 213 of the first screw section. The second seal 320 is installed in the second seal mounting groove 214. Among them, the second seal mounting groove 214 can also be processed on the outer end face 223 of the second screw section 220. The second seal 320 is preferably an O-ring.

[0052] In this embodiment, a second seal 400 is provided on the end face seal structure, that is, on the basis of the labyrinth seal structure of the small clearance fit seal behind the end face seal of the screw and the first seal, the second seal is added to form a combined seal structure, and the sealing effect is further improved.

[0053] Embodiment 5

[0054] The extruder is characterized by including the screw sealing structure in any one of Embodiments 1-4.

[0055] The present utility model is not limited to the above embodiments. Based on the technical solutions disclosed in the present utility model, those skilled in the art can make some substitutions and transformations to some of the technical features without creative labor according to the disclosed technical content, and these substitutions and transformations are all within the protection scope of the present utility model.

Claims

1. Screw seal structure, characterized in that, Comprising: Spindle; Screw rod, arranged on the spindle, the screw rod includes a plurality of screw rod segments, and a labyrinth seal structure is arranged between the corresponding end faces of adjacent screw rod segments, including an end face seal structure and a clearance seal structure arranged from outside to inside; The end face seal structure is formed by the relative outer end faces of adjacent screw rod segments being in contact with each other; The clearance seal structure includes a mating seal mounting hole and a boss arranged at the corresponding ends of adjacent screw rod segments, and the boss is arranged in the seal mounting hole to form a clearance seal structure between adjacent screw rod segments.

2. The screw seal structure according to claim 1, characterized in that The spindle and the screw rod are connected by splines.

3. The screw seal structure according to claim 2, characterized in that, The longitudinal section of the boss is square, the outer end face of the inner spline of the second screw rod segment is inclined upward, and there is a gap between the inner side wall of the boss and the upper edge of the outer end face of the inner spline of the screw rod segment.

4. The screw seal structure according to claim 2, characterized in that, The longitudinal section of the boss is a right trapezoid, and the inclined waist of the right trapezoid is the inner side wall of the boss; the outer end face of the inner spline of the screw rod segment is inclined upward; the inner side wall of the boss and the outer end face of the inner spline of the second screw rod segment coincide.

5. The screw seal structure according to claim 1, characterized in that, A first seal is arranged on the contact surface between the boss and the seal mounting hole.

6. The screw seal structure according to claim 5, characterized in that A first seal mounting groove is arranged on the outer circumferential surface of the boss, and the first seal is arranged on the first seal mounting groove.

7. The screw seal structure according to claim 5, characterized in that, A second seal is arranged on the relative outer end faces of adjacent screw rod segments.

8. An extruder, characterized in that, Including the screw rod seal structure according to any one of claims 1-7.

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