Ultrafine powder screw compressor

Abstract

The utility model provides an ultrafine powder screw compressor which comprises an outer cylinder body, the left end and the right end of the outer cylinder body are fixedly connected with a left end bearing seat and a right end bearing seat respectively, a screw shaft is installed in the outer cylinder body through the left end bearing seat and the right end bearing seat, and a transmission device is fixedly installed at one end of the outer wall of the outer cylinder body. According to the utility model, the middle cone of the spiral shaft is designed to reduce the length-diameter ratio and enlarge the cone angle, and meanwhile, the screw pitch of the spiral blade is reduced from right to left according to the arithmetic progression rule, so that the helix angle at the root of the blade is rapidly reduced, and meanwhile, the sideslip angle is reduced; the spiral blade and the middle cone are integrally formed through precision casting, the joint of the spiral blade and the middle cone is of a large arc angle structure, the surface of the large arc angle structure is polished, friction between the material at the joint and the spiral body is reduced, and circular motion of the material is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of ultrafine powder packaging, in particular to an ultrafine powder spiral compressor. Background Art

[0002] In the field of deep processing of ultrafine powders, materials that have undergone dry ultrafine processing exhibit different properties from the original material: the specific surface area increases, the surface energy rises, and at the same time, the powder contains a large amount of gas and has an extremely low bulk density, which brings great difficulties to the packaging of ultrafine powders. For example, carbon black, a rubber reinforcing agent, is difficult to package and transport in powder form, and it is not easy to disperse in rubber, which affects the performance of the final rubber product. Therefore, it must be granulated. To increase the bulk density of ultrafine powders and facilitate packaging, the industry has adopted variable-pitch screw extruders to degas the powdered material before packaging. However, to date, most of these designs and manufacturing are based on the designer's experience. During use, the material is easily squeezed and trapped in the machine, resulting in unstable operation. There are no successful cases that have been fully recognized by users.

[0003] The main components of the variable pitch screw extruder currently available on the market are an external barrel, a screw shaft rotatably connected to the barrel via support shafts at both ends, and a transmission system that drives the screw shaft to rotate. The external barrel consists of a feed section barrel, an exhaust section barrel, and a discharge section barrel, which are connected in sequence and have interconnected inner cavities. The exhaust section barrel is a breathable barrel with air-permeable micropores on its barrel wall to discharge gas during the extrusion process. Due to the micropores on the inner wall of the barrel, the inner surface is rough and has high friction resistance. During operation, the material tends to roll inside the screw and is difficult to push axially. At the same time, the material tends to adhere to the surface, squeezing the screw. In addition, the friction between the material and the barrel wall makes the micropores easily clogged. Once clogged, the exhaust will be blocked, affecting the degassing effect of the powder. To clear the blockage, some manufacturers use compressed air backblowing, but the effect is not ideal. Its internal spiral shaft is composed of a blade shaft and variable pitch spiral blades with gradually decreasing pitch wrapped and welded on its surface. The blade shaft is composed of a tapered shaft section and an equal diameter shaft section. The tapered shaft section gradually thickens from the outer end of the feed section cylinder to the outlet end of the exhaust section cylinder. The feed section spiral and the exhaust section spiral are arranged on the tapered shaft section.

[0004] The welding structure of the spiral blade and the blade shaft of the prior art is shown in the attached Figure 7The spiral blades are welded vertically to the surface of the middle cone. If the weld foot is too small, it will affect the welding strength; if the weld foot is too large, it will cause large welding stress and cause the blades to deform. At the same time, the closer the spiral blades are to the small end of the tapered shaft (feeding end), the larger the spiral angle, the greater the radial speed, and the greater the radial depth of the blades. Due to the friction between the material and the blades and the surface of the tapered shaft, circular motion will occur. The circumferential speed of the material varies within the radius length range. The circumferential speed of the material close to the tapered shaft is greater than that of the outer layer, and the axial speed is smaller than that of the outer layer. The material will also produce relative sliding during the movement in the spiral, causing the material to tumble in the spiral, affecting the extrusion effect of the screw extruder and the material push. Therefore, the present application provides an ultra-fine powder spiral compressor and a manufacturing method thereof to meet the needs. Utility Model Content

[0005] The technical problem to be solved by the utility model is to provide an ultra-fine powder spiral compressor and a manufacturing method thereof, aiming to solve the problems in the prior art that materials are easily adhered to the surface, causing the spiral to be squeezed and the micropores on the cylinder to be easily blocked, resulting in poor exhaust, affecting the degassing effect of the powder, and affecting the extrusion effect of the spiral extruder and the material pushing.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] An ultrafine powder spiral compressor comprises an outer cylinder, wherein the left and right ends of the outer cylinder are fixedly connected to a left end bearing seat and a right end bearing seat respectively, a spiral shaft is installed inside the outer cylinder through the left and right end bearing seats, a transmission device is fixedly installed on one end of the outer wall of the outer cylinder, and one end of the transmission device is connected to the spiral shaft through a coupling;

[0008] The spiral shaft includes a middle cone, a front end shaft head fixedly connected to one end of the middle cone, a rear end shaft head fixedly connected to the other end of the middle cone, and a spiral blade fixedly sleeved on the outer wall of the middle cone, the front end shaft head is fixedly connected to the left end bearing seat, the rear end shaft head is fixedly connected to the right end bearing seat, and the end of the rear end shaft head is fixedly connected to the coupling, a groove is provided on the outer circumferential surface of the spiral blade along the spiral line, the left end of the middle cone is divided into a hollow structure, and a plurality of stepped holes are provided on the left end part of the spiral blade along the spiral direction of the outer circumference, the stepped holes are used to connect the groove and the hollow structure in the middle cone, a filter with micropores is fixedly connected near the groove in the stepped hole, and an exhaust hole communicating with the hollow structure in the middle cone is provided at the axis center of the front end shaft head.

[0009] Optionally, the outer circumferential surface of the spiral blade forms a front extrusion surface and a back surface through grooves, the height of the front extrusion surface is higher than the height of the back surface, and the height difference H is 0.5-1.0 mm.

[0010] Optionally, the middle cone is designed to reduce the aspect ratio and increase the cone angle, wherein the cone angle is between 8° and 12°.

[0011] Optionally, the pitch of the spiral blade decreases from right to left according to an arithmetic progression, and a shaftless blade is fixedly connected to the right end of the spiral blade.

[0012] Optionally, the spiral blade and the middle cone are integrally formed by precision casting, and the connection between the spiral blade and the middle cone is a large arc angle structure, the large arc angle R is not less than 30 mm, and the surface is polished.

[0013] Optionally, the outer cylinder is a cylindrical single-layer structure, the inner surface of which is polished, and the inner surface of the outer cylinder is provided with a plurality of arc-shaped long grooves at equal intervals along the circumferential direction.

[0014] Optionally, a feed port is provided at the top right end of the outer cylinder, and a discharge port is provided at the bottom left end of the outer cylinder. The feed port is tilted forward at an angle γ along the material pushing direction, and the angle γ is not less than 15°.

[0015] Compared with the prior art, the present invention has at least the following beneficial effects:

[0016] 1. In the utility model, the outer cylinder is a cylindrical single-layer structure, and its inner surface is finely machined and polished to prevent the material from adhering to the surface. When pushing in the axial direction, the friction resistance is as small as possible, the axial movement is smooth, and squeezing is prevented. At the same time, the inner surface of the outer cylinder is provided with a plurality of arc-shaped long grooves at equal intervals along the circumferential direction. The arc-shaped long grooves are arranged along the axial direction of the outer cylinder. The arc-shaped long grooves can prevent the circumferential motion of the material and reduce the tumbling of the material, thereby improving the extrusion exhaust and pushing efficiency.

[0017] 2. In the present invention, the middle cone of the spiral shaft is designed to reduce the aspect ratio and increase the cone angle. At the same time, the pitch of the spiral blade decreases from right to left according to the law of arithmetic progression. While the spiral rise angle at the root of the blade decreases rapidly, the side slip angle is reduced, thereby reducing the tumbling of the material in the spiral, so that the material is compressed as quickly as possible. The spiral blade and the middle cone are precision-cast as one piece, and the connection between the spiral blade and the middle cone is a large arc angle structure, and its surface is polished to reduce the friction between the material and the spiral at this location and reduce the circular motion of the material.

[0018] 3. In the present invention, grooves are provided on the outer circumferential surface of the spiral blade, and the outer circumferential surface of the spiral blade forms a front extrusion surface and a back surface through the grooves, and a filter element 3 with micropores is installed in the stepped hole. During the material extrusion process, the material at the front extrusion surface of the spiral blade is compacted, and the material on the back surface is relatively loose, so that the filter element with micropores is not easy to be clogged, and the extruded gas can be discharged from the stepped hole and the exhaust hole through the filter element with micropores. The designed exhaust structure is not easy to be clogged and the exhaust is smooth. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings, which are incorporated herein and constitute part of the specification, illustrate embodiments of the invention and, together with the description, further serve to explain the principles of the invention and enable those skilled in the relevant art to make and use the invention.

[0020] Figure 1 This is a schematic diagram of the overall structure of the ultra-fine powder spiral compressor;

[0021] Figure 2 Schematic diagram of the spiral shaft structure;

[0022] Figure 3 Schematic diagram of the cross-sectional structure of the spiral blade and the middle cone along the AA direction;

[0023] Figure 4 This is a schematic diagram of the test cross-section structure of the outer cylinder;

[0024] Figure 5 Schematic diagram of force analysis of material particles on the spiral shaft;

[0025] Figure 6 Schematic diagram of the motion analysis of material particles on the spiral shaft;

[0026] Figure 7 It is a schematic diagram of the welding structure of the spiral blade and the middle cone in the prior art.

[0027] [Reference Signs]

[0028] 1. Left end bearing seat; 2. Outer cylinder; 21. Arc-shaped long groove; 3. Screw shaft; 31. Front end shaft head; 32. Middle cone; 33. Spiral blade; 331. Filter element with micropores; 34. Shaftless blade; 35. Rear end shaft head; 4. Feed inlet; 5. Right end bearing seat; 6. Coupling; 7. Transmission device; 8. Discharge port.

[0029] As shown in the figure, in order to clearly implement the structure of the embodiment of the present invention, specific structures and devices are marked in the figure, but this is only for illustrative purposes and is not intended to limit the present invention to the specific structure, devices and environment. According to specific needs, ordinary technicians in this field can adjust or modify these devices and environments. DETAILED DESCRIPTION

[0030] The following is a detailed description of the ultra-fine powder spiral compressor provided by the present invention, with reference to the accompanying drawings and specific embodiments. It is also noted that, in order to provide a more detailed description, the following embodiments are best and preferred embodiments, and those skilled in the art may also adopt other alternative implementations for some known technologies. Furthermore, the accompanying drawings are only for the purpose of describing the embodiments in more detail and are not intended to limit the present invention in any specific way.

[0031] It should be noted that references in the specification to "one embodiment," "an embodiment," "exemplary embodiments," "some embodiments," etc. indicate that the described embodiments may include specific features, structures, or characteristics, but not necessarily every embodiment will include such specific features, structures, or characteristics. Furthermore, when specific features, structures, or characteristics are described in conjunction with an embodiment, it is within the knowledge of persons skilled in the relevant art to implement such features, structures, or characteristics in conjunction with other embodiments (whether or not explicitly described).

[0032] In general, terms can be understood, at least in part, from their use in context. For example, depending at least in part on the context, the term "one or more" as used herein can be used to describe any feature, structure, or characteristic in the singular sense, or can be used to describe a combination of features, structures, or characteristics in the plural sense. Additionally, the term "based on" can be understood as not necessarily intended to convey an exclusive set of factors, but can instead, depending at least in part on the context, allow for the presence of other factors that are not necessarily explicitly described.

[0033] It will be understood that the meanings of “on,” “over,” and “above” in the present invention should be interpreted in the broadest manner, so that “on” means not only “directly on” something but also includes the meaning of being “on” something with intervening features or layers, and “on” or “above” means not only “on” or “above” something but also includes the meaning of being “on” or “above” something with no intervening features or layers.

[0034] Additionally, spatially relative terms such as "below," "beneath," "lower," "above," and "upper" may be used herein for descriptive convenience to describe the relationship of one element or feature to another element or features, as illustrated in the accompanying drawings. Spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the accompanying drawings. The device may be oriented in other ways, and the spatially relative descriptors used herein should be similarly interpreted accordingly.

[0035] like Figures 1-6 As shown, an embodiment of the present invention provides an ultra-fine powder spiral compressor, comprising an outer cylinder 2, the left and right ends of the outer cylinder 2 are respectively fixedly connected with a left end bearing seat 1 and a right end bearing seat 5, a spiral shaft 3 is installed inside the outer cylinder 2 through the left end bearing seat 1 and the right end bearing seat 5, a transmission device 7 is fixedly installed at one end of the outer wall of the outer cylinder 2, one end of the transmission device 7 is connected to the spiral shaft 3 through a coupling 6, a feed port 4 is provided at the top of the right end of the outer cylinder 2, and a discharge port 8 is provided at the bottom of the left end of the outer cylinder 2. When working, the fine powder material is added to the interior of the outer cylinder 2 from the feed port 4, and the transmission device 7 is driven to rotate inside the outer cylinder 2, and the fine powder material is spirally compressed and discharged through the discharge port 8.

[0036] In this embodiment, if Figure 1 and Figure 4 As shown, the outer cylinder 2 is a cylindrical single-layer structure. Compared with the prior art, the outer cylinder 2 has removed the microporous filter tube and no longer bears the exhaust function during the extrusion process; its inner surface is finely processed and polished to prevent the material from adhering to the surface. When pushing in the axial direction, the friction resistance is as small as possible, the axial movement is smooth, and squeezing is prevented; at the same time, the inner surface of the outer cylinder 2 is provided with a plurality of arc-shaped long grooves 21 at equal intervals along the circumferential direction. The arc-shaped long grooves 21 are arranged along the axial direction of the outer cylinder 2. The arc-shaped long grooves 21 can prevent the circumferential motion of the material and reduce the tumbling of the material, thereby improving the extrusion exhaust and pushing efficiency.

[0037] In this embodiment, if Figure 2 As shown, the spiral shaft 3 includes a middle cone 32, a front end shaft head 31 fixedly connected to one end of the middle cone 32, a rear end shaft head 35 fixedly connected to the other end of the middle cone 32, and a spiral blade 33 fixedly sleeved on the outer wall of the middle cone 32. The middle cone 32, the front end shaft head 31 and the rear end shaft head 35 are formed as one piece. The front end shaft head 31 is fixedly connected to the left end bearing seat 1, the rear end shaft head 35 is fixedly connected to the right end bearing seat 5, and the end of the rear end shaft head 35 is fixedly connected to the coupling 6 to complete the installation of the spiral shaft 3 in the outer cylinder 2.

[0038] In this embodiment, if Figure 2 As shown, the middle cone 32 is designed to reduce the aspect ratio and increase the cone angle, wherein the cone angle is between 8° and 12°. At the same time, the pitch of the spiral blade 33 decreases from right to left according to the law of arithmetic progression. While the spiral rise angle at the root of the blade decreases rapidly, the side slip angle is reduced, thereby reducing the tumbling of the material in the spiral, so that the material is compressed as quickly as possible.

[0039] In this embodiment, if Figure 3As shown, the spiral blade 33 and the middle cone 32 are integrally formed by precision casting. The connection between the spiral blade 33 and the middle cone 32 is a large arc angle structure, and the large arc angle R is not less than 30 mm. Its surface is polished to reduce the friction between the material and the spiral body and reduce the circular motion of the material.

[0040] In this embodiment, a groove is provided on the outer circumferential surface of the spiral blade 33 along the spiral line. The outer circumferential surface of the spiral blade 33 forms a front extrusion surface and a back surface through the groove. The height of the front extrusion surface is higher than the height of the back surface, and the height difference H is 0.5-1.0 mm. The left end portion of the middle cone 32 is divided into a hollow structure. A plurality of stepped holes are provided on the left end portion of the spiral blade 33 along the spiral direction of the outer circumference. The stepped holes are used to connect the groove and the hollow structure in the middle cone 32. A microporous filter 331 is fixedly connected to the stepped hole near the groove. An exhaust hole communicating with the hollow structure in the middle cone 32 is provided at the axis center of the front end shaft head 31. During the material extrusion process, the material at the front extrusion surface of the spiral blade 33 is compacted, and the material on the back surface is relatively loose, so that the microporous filter 331 is not easy to be blocked, and the extruded gas can be discharged from the stepped holes and the exhaust hole through the microporous filter 331. The designed exhaust structure is not easy to be blocked and the exhaust is smooth.

[0041] In this embodiment, if Figure 2 As shown, a shaftless blade 34 is fixedly connected to the right end of the spiral blade 33 to clean the accumulated materials at the feeding end.

[0042] In this embodiment, if Figure 1 As shown, the feed port 4 is tilted forward at an angle γ along the material pushing direction, and the angle γ is not less than 15°, which is conducive to material filling and pushing.

[0043] like Figure 5 As shown, in this embodiment, the method for analyzing the axial force of the material particles on the screw shaft 3 is:

[0044] P 轴 =P.cos(α+β)

[0045] Among them, P is the comprehensive force of the material, α is the helix angle of the spiral at that point, and β is the friction angle between the material and the blade.

[0046] like Figure 6 As shown, the design method of the axial velocity of the material particles on the screw shaft 3 is:

[0047] V 轴 =V.cos(α+β)

[0048] The design method of the radial velocity of the material particles on the screw shaft 3 is:

[0049] V 径=V.sin(α+β)

[0050] Among them, V is the movement speed of the material particles, α is the helix angle of the spiral at that point, and β is the friction angle between the material and the blade.

[0051] It can be seen from the above formula that the axial force and axial velocity of the material particles increase as (α+β) decreases, while the radial velocity decreases as (α+β) decreases. By reducing the aspect ratio of the middle cone 32 on the spiral shaft 3, reducing the pitch, quickly reducing the helix angle α at the root of the spiral blade 33, and reducing the roughness of the spiral, the friction angle β is reduced, the radial velocity of the material particles is reduced, the axial velocity of the material particles is increased, and the axial extrusion force is increased, the tumbling of the material in the spiral shaft 3 is reduced, and the extrusion and exhaust capacity and compression effect of the material are improved.

[0052] This invention encompasses any alternatives, modifications, equivalents, and solutions that do not depart from the spirit and scope of this invention. To provide a thorough understanding of this invention, specific details are described in detail in the following preferred embodiments of this invention, but those skilled in the art will be able to fully understand this invention without these detailed descriptions. Furthermore, to avoid unnecessary confusion regarding the essence of this invention, well-known methods, processes, procedures, components, and circuits are not described in detail.

[0053] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. An ultra-fine powder spiral compressor, characterized in that: The outer cylinder (2) comprises an outer cylinder (2), wherein the left end bearing seat (1) and the right end bearing seat (5) are fixedly connected to the left and right ends of the outer cylinder (2), respectively; a screw shaft (3) is installed inside the outer cylinder (2) through the left end bearing seat (1) and the right end bearing seat (5); a transmission device (7) is fixedly installed on one end of the outer wall of the outer cylinder (2), and one end of the transmission device (7) is connected to the screw shaft (3) through a coupling (6); The spiral shaft (3) includes a middle cone (32), a front end shaft head (31) fixedly connected to one end of the middle cone (32), a rear end shaft head (35) fixedly connected to the other end of the middle cone (32), and a spiral blade (33) fixedly sleeved on the outer wall of the middle cone (32), wherein the front end shaft head (31) is fixedly connected to the left end bearing seat (1), the rear end shaft head (35) is fixedly connected to the right end bearing seat (5), and the end of the rear end shaft head (35) is fixedly connected to the coupling (6). A groove is provided on the outer circumferential surface of the spiral blade (33) along a spiral line, and the left end portion of the middle cone (32) is divided into a hollow structure. A plurality of stepped holes are provided on the left end portion of the spiral blade (33) along the outer circumferential spiral direction, and the stepped holes are used to connect the groove with the hollow structure in the middle cone (32). A filter element (331) with micropores is fixedly connected to the stepped holes near the groove, and an exhaust hole is provided at the axis center of the front end shaft head (31) and communicates with the hollow structure in the middle cone (32).

2. The ultra-fine powder spiral compressor according to claim 1, characterized in that: The outer circumferential surface of the spiral blade (33) is formed with a front extrusion surface and a back surface through grooves, and the height of the front extrusion surface is higher than the height of the back surface, and the height difference H is 0.5-1.0 mm.

3. The ultra-fine powder spiral compressor according to claim 1, characterized in that: The middle cone (32) is designed to reduce the aspect ratio and increase the cone angle, wherein the cone angle is between 8° and 12°.

4. The ultra-fine powder spiral compressor according to claim 1, characterized in that: The pitch of the spiral blade (33) decreases from right to left according to an arithmetic progression, and a shaftless blade (34) is fixedly connected to the right end of the spiral blade (33).

5. The ultra-fine powder spiral compressor according to claim 4, characterized in that: The spiral blade (33) and the middle cone (32) are integrally formed by precision casting. The connection between the spiral blade (33) and the middle cone (32) is a large arc angle structure, the large arc angle R is not less than 30 mm, and the surface is polished.

6. The ultra-fine powder spiral compressor according to claim 1, characterized in that: The outer cylinder (2) is a cylindrical single-layer structure, and its inner surface is polished. The inner surface of the outer cylinder (2) is provided with a plurality of arc-shaped long grooves (21) at equal intervals along the circumferential direction.

7. The ultra-fine powder spiral compressor according to claim 1, characterized in that: A feed port (4) is provided at the top of the right end of the outer cylinder (2), and a discharge port (8) is provided at the bottom of the left end of the outer cylinder (2). The feed port (4) is tilted forward at an angle γ along the material pushing direction, and the angle γ is not less than 15°.

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