Circulating screw extruder

Abstract

The invention relates to a circulating screw extruder. Comprising a transversely-arranged cylindrical barrel, a feeding pipe vertically inserted into the upper side of the left end of the cylindrical barrel and communicated with the interior of the cylindrical barrel, a discharging pipe vertically inserted into the lower side of the right end of the cylindrical barrel and communicated with the interior of the cylindrical barrel, and a feeding valve arranged between the root of the feeding pipe and the cylindrical barrel. The discharging valve is arranged between the root of the discharging pipe and the cylindrical barrel, and the end cover is detachably fixed to an opening in the right end of the cylindrical barrel; the device further comprises a circulating extrusion assembly. The circulating extrusion assembly comprises an outer circulating screw rod, an inner circulating screw rod and a driving mechanism; according to the invention, the material mixing uniformity is greatly improved, the operation is greatly simplified, and the effects of saving time and labor are achieved; in addition, the extrusion speed of the materials is effectively increased.

Description

Technical Field

[0001] The invention relates to a circulating screw extruder. Background Art

[0002] Screw extruders are required for both mixing and molding of materials. Screw extruders can be divided into single-screw extruders, twin-screw extruders and multi-screw extruders according to the number of screws. Single-screw extruders are widely used because they are easy to manufacture, have high processing efficiency and are cheap. They are the most mature and widely used type of extruders. However, the uniformity of material mixing in existing single-screw extruders depends on the length of the screw, because the longer the screw, the longer the distance the material moves in the shell of the single-screw extruder and the longer the residence time. However, in order to save space, the length of the screw cannot be too long, so the uniformity of material mixing is low and cannot be effectively improved. The only way is to repeatedly transfer the extruded material and feed it into the shell for multiple extrusions, but the operation is more cumbersome, and the transfer and feeding of materials are time-consuming and labor-intensive, which urgently needs to be solved. Summary of the invention

[0003] In view of the current status of the above-mentioned prior art, the technical problem to be solved by the present invention is to provide a circulating screw extruder which not only saves space and greatly improves the uniformity of material mixing, but also greatly simplifies the operation and achieves the effect of saving time and labor, and can effectively speed up the extrusion speed of materials.

[0004] The technical solution adopted by the present invention to solve the above technical problems is: a circulating screw extruder, comprising a horizontally arranged cylindrical barrel, a feed pipe vertically plugged into the upper left end of the cylindrical barrel and interconnected with the inside of the cylindrical barrel, a discharge pipe vertically plugged into the lower right end of the cylindrical barrel and interconnected with the inside of the cylindrical barrel, a feed valve arranged between the root of the feed pipe and the cylindrical barrel, a discharge valve arranged between the root of the discharge pipe and the cylindrical barrel, and a detachable end cover fixed at the opening of the right end of the cylindrical barrel, characterized in that:

[0005] It also includes a circulation extrusion assembly; the circulation extrusion assembly includes an outer circulation screw, an inner circulation screw and a driving mechanism, the outer circulation screw is transversely and concentrically arranged inside the cylindrical barrel, a concentrically distributed columnar circulation cavity is opened between the two ends of the outer circulation screw, the inner circulation screw is transversely and concentrically arranged in the columnar circulation cavity, and the right end of the outer circulation screw and the right end of the inner circulation screw are both rotatably connected to the end cover;

[0006] A plurality of first material penetration holes uniformly distributed at equal angles along the circumferential direction are formed on the outer circumferential surface at the left end of the outer circulation screw, and a plurality of second material penetration holes uniformly distributed at equal angles along the circumferential direction are formed on the outer circumferential surface at the right end of the outer circulation screw;

[0007] The driving mechanism comprises a transmission box fixed to the left end of the cylindrical body, a box cover detachably fixed to the left opening of the transmission box, and a main body arranged inside the transmission box and connected to both the outer circulation screw and the inner circulation screw;

[0008] The left end of the outer circulation screw and the left end of the inner circulation screw both move through the left end of the cylindrical body and are both rotatably connected to the right side of the transmission box and extend into the interior of the transmission box.

[0009] Preferably, the main body includes an outer gear ring fixed on the left end of the outer circulation screw, a first transmission shaft which is laterally and rotatably connected to the transmission box and located on the rear side of the outer gear ring, a first gear fixed on the first transmission shaft and meshing with the outer gear ring, and a reduction motor fixed in the transmission box, wherein the rotating shaft of the reduction motor is concentrically fixed to one end of the first transmission shaft.

[0010] Preferably, the main body also includes a second transmission shaft which is laterally and rotatably connected to the transmission box and located in front of the outer gear ring, a second gear which is sleeved and fixed on the second transmission shaft and meshed with the outer gear ring, and a clutch unit arranged between the first transmission shaft and the second transmission shaft.

[0011] Preferably, the clutch unit includes a third gear sleeved and fixed on the left end of the inner circulation screw and located on the left side of the outer gear ring, a swing rod rotatably connected to the left end of the inner circulation screw, a fourth gear sleeved and fixed on the first transmission shaft and located on the left side of the first gear, a third transmission shaft laterally and rotatably connected to the transmission box and located between the first transmission shaft and the swing rod, a fifth gear sleeved and fixed on the second transmission shaft and located on the left side of the second gear, a sixth gear sleeved and fixed on the third transmission shaft and meshed with the fourth gear, and a seventh gear rotatably connected to one end of the swing rod and meshed with the third gear and coordinated with both the fifth gear and the sixth gear.

[0012] Preferably, the clutch unit further comprises an electric cylinder, a fixed end of the electric cylinder is rotatably connected to the inner wall of the transmission box, and a telescopic end of the electric cylinder is rotatably connected to the other end of the swing rod.

[0013] Preferably, a material stopper ring is sleeved and fixed on the left end of the inner circulation screw, and the material stopper ring is movably arranged at the inner left end of the columnar circulation cavity and slidably fits on the inner wall of the left end of the cylindrical barrel.

[0014] Compared with the prior art, the advantages of the present invention are: the present invention can make the material circulate continuously in the cylindrical barrel and the columnar circulation chamber. As long as the feed valve and the discharge valve are kept closed, the material can stay in the cylindrical barrel and the columnar circulation chamber for any length of time and maintain a circulating state. In this way, the length of the screw can be greatly shortened to save space, and at the same time, the uniformity of material mixing is greatly improved. There is no need for frequent transfer and feeding of materials, which greatly simplifies the operation and achieves the effect of saving time and effort. In addition, the clutch unit can be used to change the rotation direction of the inner circulation screw, and then the material can be extruded synchronously after the mixing is completed to effectively speed up the extrusion speed of the material. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is the exploded structural diagram of the left front side of the present invention;

[0016] Figure 2 It is the exploded structural diagram of the left front side of the driving mechanism of the present invention. DETAILED DESCRIPTION

[0017] Unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0018] In order to keep the following description of the embodiments of the present invention clear and concise, detailed descriptions of well-known functions and well-known components are omitted.

[0019] like Figures 1-2As shown, a circulating screw extruder comprises a horizontally arranged cylindrical barrel 1, a feed pipe 3 vertically plugged into the upper left end of the cylindrical barrel 1 and interconnected with the inside of the cylindrical barrel 1, a discharge pipe 10 vertically plugged into the lower right end of the cylindrical barrel 1 and interconnected with the inside of the cylindrical barrel 1, a feed valve 2 arranged between the root of the feed pipe 3 and the cylindrical barrel 1, a discharge valve 9 arranged between the root of the discharge pipe 10 and the cylindrical barrel 1, and an end cover 8 detachably fixed to the opening at the right end of the cylindrical barrel 1; it also comprises a circulating extrusion assembly; the circulating extrusion assembly comprises an outer circulating screw 4, an inner circulating screw 5 and a driving mechanism 7, the outer circulating screw 4 is horizontally and concentrically arranged inside the cylindrical barrel 1, a concentrically distributed columnar circulating cavity 41 is opened between the two ends of the outer circulating screw 4, and the inner circulating screw 5 is horizontally and concentrically arranged at the column In the circulation chamber 41, the right end of the outer circulation screw 4 and the right end of the inner circulation screw 5 are both rotatably connected to the end cover 8, and a plurality of first material-transmitting holes 42 uniformly distributed at equal angles in the circumferential direction are provided on the outer circumferential surface of the left end of the outer circulation screw 4, and a plurality of second material-transmitting holes 43 uniformly distributed at equal angles in the circumferential direction are provided on the outer circumferential surface of the right end of the outer circulation screw 4; the driving mechanism 7 includes a transmission box 71 fixed to the left end of the cylindrical body 1, a box cover 72 detachably fixed to the left opening of the transmission box 71, and a main body arranged inside the transmission box 71 and connected to both the outer circulation screw 4 and the inner circulation screw 5; the left end of the outer circulation screw 4 and the left end of the inner circulation screw 5 both move through the left end of the cylindrical body 1 and are both rotatably inserted and connected to the right side of the transmission box 71 and both extend into the interior of the transmission box 71.

[0020] The main body includes an outer ring gear 76 sleeved and fixed on the left end of the outer circulation screw 4, a first transmission shaft 74 which is laterally and rotatably connected to the transmission box 71 and is located on the rear side of the outer ring gear 76, a first gear 75 sleeved and fixed on the first transmission shaft 74 and meshing with the outer ring gear 76, and a reduction motor 73 fixed in the transmission box 71, and the rotating shaft of the reduction motor 73 is concentrically fixed to one end of the first transmission shaft 74.

[0021] The main body also includes a second transmission shaft 77 which is laterally and rotatably connected to the transmission box 71 and located in front of the outer gear ring 76, a second gear 78 which is sleeved and fixed on the second transmission shaft 77 and meshed with the outer gear ring 76, and a clutch unit arranged between the first transmission shaft 74 and the second transmission shaft 77.

[0022] The clutch unit includes a third gear 711 which is sleeved and fixed on the left end of the inner circulation screw 5 and located on the left side of the outer gear ring 76, a swing rod 712 rotatably connected to the left end of the inner circulation screw 5, a fourth gear 710 sleeved and fixed on the first transmission shaft 74 and located on the left side of the first gear 75, a third transmission shaft 715 which is laterally and rotatably connected to the transmission box 71 and located between the first transmission shaft 74 and the swing rod 712, a fifth gear 79 which is sleeved and fixed on the second transmission shaft 77 and located on the left side of the second gear 78, a sixth gear 716 which is sleeved and fixed on the third transmission shaft 715 and meshed with the fourth gear 710, and a seventh gear 713 which is rotatably connected to one end of the swing rod 712 and meshed with the third gear 711 and cooperates with both the fifth gear 79 and the sixth gear 716.

[0023] The clutch unit further includes an electric cylinder 714 , a fixed end of the electric cylinder 714 is rotatably connected to the inner wall of the transmission box 71 , and a telescopic end of the electric cylinder 714 is rotatably connected to the other end of the swing rod 712 .

[0024] A material stopper ring 6 is sleeved and fixed on the left end of the inner circulation screw 5 . The material stopper ring 6 is movably arranged at the inner left end of the columnar circulation chamber 41 and slidably fits on the inner wall of the left end of the cylindrical barrel 1 .

[0025] Working principle:

[0026] After the material is passed into the feed pipe 3 and the feed valve 2 is opened, the material in the feed pipe 3 will enter the left end of the cylindrical barrel 1; the reduction motor 73 in the main body is started to rotate its rotating shaft, and then the first gear 75 is driven to rotate with the help of the first transmission shaft 74, thereby driving the outer circulation screw 4 to rotate with the help of the outer gear ring 76, and then driving the material to move to the right.

[0027] In order to fully mix the materials, close the feed valve 2 and keep the discharge valve 9 in a closed state, then drive the telescopic end of the electric cylinder 714 to extend outward to rotate around the inner circulation screw 5 with the help of the swing rod 712, so that the seventh gear 713 swings in the direction of the sixth gear 716 until the seventh gear 713 is meshed with the sixth gear 716. Since the fourth gear 710 rotates with the first transmission shaft 74 and meshes with the sixth gear 716, and since the seventh gear 713 is meshed with the third gear 711, the first transmission shaft 74 will drive the third gear 711 to rotate with the help of the fourth gear 710 and the sixth gear 716, thereby driving the inner circulation The screw 5 rotates in the columnar circulation chamber 41, and the material conveying direction of the inner circulation screw 5 is opposite to that of the outer circulation screw 4. The material reaching the right end of the cylindrical body 1 cannot be discharged outward through the discharge pipe 10 due to the closure of the discharge valve 9, so it will enter the right end of the columnar circulation chamber 41 through multiple second material holes 43, and then move to the left under the action of the inner circulation screw 5. When the material reaches the left end of the columnar circulation chamber 41, the material will return to the inner left end of the cylindrical body 1 through multiple first material holes 42, and then move to the right under the action of the outer circulation screw 4, thereby realizing repeated circulation and mixing of the material.

[0028] After the materials are circulated and mixed for a period of time, the telescopic end of the driving electric cylinder 714 contracts inwardly to drive the seventh gear 713 to leave the sixth gear 716 and swing in the direction of the fifth gear 79 until the seventh gear 713 meshes with the fifth gear 79; since the second gear 78 meshes with the outer gear ring 76, the rotation of the outer gear ring 76 will drive the second transmission shaft 77 to rotate with the help of the second gear 78, and then drive the fifth gear 79 to rotate, thereby driving the third gear 711 to rotate with the help of the seventh gear 713, and then also driving the inner circulation screw 5 to rotate, but the rotation direction of the inner circulation screw 5 has been opposite to the original On the contrary, the rotation direction of the outer circulation screw 4 does not change, and the material conveying direction of the inner circulation screw 5 is the same as that of the outer circulation screw 4, so the inner circulation screw 5 will drive the material retained in the columnar circulation chamber 41 to move to the right and enter the right end of the inner part of the cylindrical body 1 through multiple second material holes 43, and the material located inside the cylindrical body 1 also moves to the right under the action of the outer circulation screw 4; thereafter, the discharge valve 9 is opened, and the material located at the right end of the inner part of the cylindrical body 1 will be discharged outward through the discharge pipe 10, thereby speeding up the output of the material and preventing the material from being retained in the columnar circulation chamber 41.

[0029] The present invention can make the material circulate continuously in the cylindrical barrel 1 and the columnar circulation chamber 41. As long as the feed valve 2 and the discharge valve 9 are kept closed, the material can stay in the cylindrical barrel 1 and the columnar circulation chamber 41 for any length of time and maintain a circulating movement state. In this way, the length of the screw can be greatly shortened to save space, and at the same time, the uniformity of material mixing is greatly improved. There is no need for frequent transfer and feeding of materials, which greatly simplifies the operation and achieves the effect of saving time and labor. In addition, the clutch unit can be used to change the rotation direction of the inner circulation screw 5, and then the material can be extruded synchronously after the mixing is completed to effectively speed up the extrusion speed of the material.

[0030] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A circulating screw extruder, comprising a horizontally arranged cylindrical body, a feed pipe vertically plugged into the upper left end of the cylindrical body and interconnected with the inside of the cylindrical body, a discharge pipe vertically plugged into the lower right end of the cylindrical body and interconnected with the inside of the cylindrical body, a feed valve arranged between the root of the feed pipe and the cylindrical body, a discharge valve arranged between the root of the discharge pipe and the cylindrical body, and an end cap detachably fixed to the opening at the right end of the cylindrical body, characterized in that: It also includes a circulation extrusion assembly; the circulation extrusion assembly includes an outer circulation screw, an inner circulation screw and a driving mechanism, the outer circulation screw is transversely and concentrically arranged inside the cylindrical barrel, a concentrically distributed columnar circulation cavity is opened between the two ends of the outer circulation screw, the inner circulation screw is transversely and concentrically arranged in the columnar circulation cavity, and the right end of the outer circulation screw and the right end of the inner circulation screw are both rotatably connected to the end cover; A plurality of first material penetration holes uniformly distributed at equal angles along the circumferential direction are formed on the outer circumferential surface at the left end of the outer circulation screw, and a plurality of second material penetration holes uniformly distributed at equal angles along the circumferential direction are formed on the outer circumferential surface at the right end of the outer circulation screw; The driving mechanism comprises a transmission box fixed to the left end of the cylindrical body, a box cover detachably fixed to the left opening of the transmission box, and a main body arranged inside the transmission box and connected to both the outer circulation screw and the inner circulation screw; The left end of the outer circulation screw and the left end of the inner circulation screw both move through the left end of the cylindrical body and are both rotatably connected to the right side of the transmission box and extend into the interior of the transmission box.

2. A circulating screw extruder according to claim 1, characterized in that: The main body includes an outer gear ring fixed on the left end of the outer circulation screw, a first transmission shaft laterally and rotatably connected to the transmission box and located at the rear side of the outer gear ring, a first gear fixed on the first transmission shaft and meshing with the outer gear ring, and a reduction motor fixed in the transmission box, wherein the rotating shaft of the reduction motor is concentrically fixed to one end of the first transmission shaft.

3. A circulating screw extruder according to claim 2, characterized in that: The main body also includes a second transmission shaft which is laterally and rotatably connected to the transmission box and located in front of the outer gear ring, a second gear which is sleeved and fixed on the second transmission shaft and meshed with the outer gear ring, and a clutch unit which is arranged between the first transmission shaft and the second transmission shaft.

4. A circulating screw extruder according to claim 3, characterized in that: The clutch unit includes a third gear sleeved and fixed on the left end of the inner circulation screw and located on the left side of the outer gear ring, a swing rod rotatably connected to the left end of the inner circulation screw, a fourth gear sleeved and fixed on the first transmission shaft and located on the left side of the first gear, a third transmission shaft laterally and rotatably connected to the transmission box and located between the first transmission shaft and the swing rod, a fifth gear sleeved and fixed on the second transmission shaft and located on the left side of the second gear, a sixth gear sleeved and fixed on the third transmission shaft and meshed with the fourth gear, and a seventh gear rotatably connected to one end of the swing rod and meshed with the third gear and coordinated with both the fifth gear and the sixth gear.

5. A circulating screw extruder according to claim 4, characterized in that: The clutch unit further comprises an electric cylinder, a fixed end of the electric cylinder is rotatably connected to the inner wall of the transmission box, and a telescopic end of the electric cylinder is rotatably connected to the other end of the swing rod.

6. A circulating screw extruder according to claim 5, characterized in that: The left end of the inner circulation screw is also sleeved and fixed with a material blocking ring, which is movably arranged at the inner left end of the columnar circulation cavity and slidably fits on the inner wall of the left end of the cylindrical barrel.

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