Pulp paper shredder

Abstract

The present invention provides a pulp paper shredder, which achieves a hand-shredding effect, produces pulp sheets having uniform appearance size, fluff around same, no shear hard marks and less fine powder in finished products, prevents screen blinding and fire, is easy to use, and has a long service life. The pulp paper shredder mainly comprises a feed port (1), hammers (2), a rotor (3), a screen plate (9), a screen carriage (5), a discharge port (7), a machine body (8), and a motor (6). Two fixed blades (14) are provided below the feed port (1); press rollers (13) are provided at a position close to the top of the fixed blades (14); the disc of the rotor (3) is in the shape of giant teeth, and blade holders are provided on the giant teeth, so that the front end surfaces of the hammers (2) can be arranged to form a seamless circumferential shape on an end surface of the rotor (3) by means of connection; in the axial plane of the rotor (3), the blade holders on the rotor (3) are divided into three groups or more; and the hammers are finger hammers (2).

Description

Pulp and paper shredder Technical Field

[0001] The invention relates to a pulverizing device used in the textile, papermaking and other industries, in particular to a pulp and paper pulverizer for lyocell raw materials. Background Art

[0002] Pulp and paper impregnation and swelling is a crucial step in the spinning solution process for the Lyocell fiber manufacturing industry. This process requires a pulverizer to hand-shred the pulp and paper into sheets of various specifications. However, these sheets must be uniform in size, with minimal tolerances, a hand-torn finish, a fuzzy finish, and no shear marks. The finished product must be free of, or minimally pulverized, fines. Specifications can range from 3-6 mm, 20-25 mm, 30-35 mm, and 40-45 mm. This ensures that, under the same time conditions, solvent concentration profile, temperature profile, and external pressure, initial dissolution is avoided, while sustained, simultaneous swelling is maintained. This results in consistent, thorough impregnation of the pulp and paper, even eliminating white spots and ultimately producing a high-quality spinning solution. Existing similar pulverizing equipment includes: a shearing device for paper processing (CN214418902U), a raw pulp paper pulverizer (CN108951242), a pulp pulverizer (CN2084409905), a pulp pulverizer for paper production (CN214529920U), and a hammer pulverizer (CN202221363577.5). These pulverizers all have drawbacks. Some use shearing pulverizers, resulting in hard lumps around the material and uneven shapes and sizes, making them unqualified. Some use large mesh screens or no screen at all, resulting in large finished products ranging from 1 to 50 mm in size and uneven force, making them unqualified. Some use circular pulverization, which reduces the size of the paper pieces but results from multiple hammer blows, resulting in uneven hard marks and a high amount of fine powder, making them unqualified.

[0003] This type of pulverizer typically consists of a feed inlet, a machine body, a rotor, hammers, a screen, a screen press, a motor, and a discharge port. During operation, the motor drives the rotor, causing the hammers to rotate. Material enters through the feed inlet and is continuously struck by the hammers, reducing its size. The pulverized material passes through the screen apertures, which control the particle size. Acceptable material is discharged from the pulverizer's discharge port. Addressing the uneven size of finished pulp and paper products is a major challenge in this project. This is particularly true during the pulverization of tail paper, which can introduce large chunks of material, causing a sudden increase in the volume of material within the pulverizer. This results in uneven hammering and a varying hardness and size of the finished product.

[0004] Since 1939, when the American company Enka successfully produced cellulose fibers by dissolving them in a NMMO solution in a coagulation bath, numerous scientists and engineers, both domestically and internationally, including those from the United States, Germany, France, Russia, Austria, Japan, and South Korea, have invested substantial capital and manpower in the development of pulp and paper pulverizers, but to no avail. These issues have long plagued the processing of lyocell raw materials, becoming a recognized industry challenge.

[0005] Summary of the Invention

[0006] The purpose of the present invention is to provide a pulp and paper pulverizer with a hand-tearing and pulverizing effect. The pulp and paper products produced are uniform in size, have fluff on the periphery, have no shear marks, have little fine powder, prevent screen blockage and fire, are easy to use and have a long service life.

[0007] The purpose of the present invention can be achieved through the following technical solutions: a pulp and paper shredder, mainly including a feed port, a hammer, a rotor, a screen, a screen press, a discharge port, a machine body, and a motor. The feature of the feed port is that one side is straight and the other side is inclined, so that if a piece of paper gets stuck, it is convenient to take the paper out from the inclined port. Two fixed knives are relatively installed below the feed port. The fixed knives have an arc-shaped working angle to prevent the formation of hard lumps of paper. The mounting hole of the fixed knife is a waist hole, so that the distance between the fixed knife and the hammer can be adjusted up and down. There is a pressure wheel near the top of the fixed knife. The pressure wheel has a spring to adjust the pressure. The pressure wheel is close to the fixed knife, which is conducive to shortening the length of the pulp and paper tail and promoting uniformity of the paper product. The rotor's disc is shaped like giant teeth, each of which is divided into eight or more equal parts. Each giant tooth is equipped with two sets of tool holders, each with two holes, for a total of four holes. One set of holes is used to install hammers, and the other set is a spare set. When one set of holes is worn and deformed, the rotor can be replaced without replacing the rotor. This can extend the rotor's service life exponentially and also facilitate the extraction of pins when replacing adjacent sets of hammers. In the axial plane of the rotor, the rotor tool holders are divided into three or more groups. In the end plane of the rotor, each group is separated by an angle of degrees, so that the arrangement of the hammer end faces can form a circular shape in the cross-section of the rotor. In the axial plane of the rotor, there are a considerable number of hammers at any point on the circumference. The tops of the hammers form a certain width, pressing against the leading edge of the paper. The purpose is to prevent the tail end of the paper from suddenly falling off without the pressure roller pressing it, and to avoid uneven paper production. The hammer of a pulp and paper shredder is a finger-shaped hammer. Two pin holes are located at one end of the hammer body to prevent the hammer from shaking. Two pins are used to connect it to the shredder's rotor blade holder to reduce the impact of shaking. The other end is the working end face. The two corners of the working end face are finger-shaped, without sharp corners or edges. They are sintered from tungsten carbide to form an elliptical spherical shape with a rough friction surface to prevent the formation of paper lumps. There is a groove in the middle of the working end face, and a palm scraper is welded into the groove. The front end of the palm scraper has uniform finger-shaped members with uniform grooves between the fingers. The fingers and the grooves are of the same width. The two corners of the fingers are sintered from tungsten carbide to form an elliptical spherical shape with no sharp corners or edges. They have a rough friction surface to prevent the formation of paper lumps. There is a mounting groove at the other end of the palm scraper, which is vertically embedded and welded with the groove in the middle of the working end face of the hammer matrix. The thickness of the finger-shaped member 19 is smaller than the width of the working end face of the hammer matrix, and the ratio of the two is between 1 / 2 and 1 / 5. This is also the key technology for producing intermittent feeding state, and it is also the key technology for solving the problem of uniform crushing of tailings. When working, the front corner of the working end face of the hammer matrix first touches the leading edge of the paper. Because it touches the paper first, a groove is broken in the paper, and then multiple finger-shaped members tear the paper. At this time, due to the long working end face, the paper groove rides on the working end face, and the paper is supported. After the working end face, feeding starts again, forming a feed, stop, feed, stop working state, which effectively prevents large pieces of tailings from entering the crusher at the same time when the pressure of the pressure roller is lost.The screen is mounted on a press frame, beneath which a vibration motor is installed. The press frame is separated from the machine body by a spring-loaded vibration isolation device, allowing the connected screen and press frame to vibrate independently and simultaneously. The finger hammers are kept at a safe distance from the screen, preventing them from colliding. Another type of finger hammer (2) is also available: a palm-type scraper with a finger-like element at the front without a groove, which can produce large flakes.

[0008] When the pulverizer is operating, the pulp sheets are pushed downward by the pressure generated between the conveyor belt 11 and the pressure roller 12, and then vertically enter the pulverizer through the pressure rod and fixed hammer. The two fixed hammers have an arc-shaped working angle, which does not produce hard marks on the pulp and paper. The finger hammers hammer the paper sheets tangentially. All working surfaces that come into contact with the pulp and paper are manufactured in a finger-shaped manner, without sharp corners or sharp edges. They are sintered from tungsten carbide into an ellipsoidal sphere with a rough friction surface, creating a hand-torn paper effect. The edges of the small pieces are plush and free of hard marks. The rotor is divided into multiple groups of evenly spaced and staggered tool holders, so that the end faces of the hammers form a seamless circumference. This ensures that there is always a group of hammers to support the tail end of the descending paper sheet, and no large piece tail end will suddenly rush into the pulverizer cavity, resulting in uneven finished products. The rotational speed of the finger hammer 2 coordinates with the feed rate of the belt conveyor 11 to control the length of the small paper pieces. The width of the finger 19 and the slot can be adjusted to control the width of the small paper pieces, thereby producing pulp and paper of a desired size. As the pulp and paper enter the pulverizer, it is constantly torn, bent, dragged, and pushed upward by the hammer 2, resulting in an intermittent feed-stop-feed-stop pattern. Two pin holes are provided at one end of the hammer body to prevent the finger hammer from shaking during operation, ensuring a more uniform distribution of the small paper pieces. The thickness of the fingers is smaller than the width of the hammer's working end face, a key feature of the intermittent feeding process and the uniform crushing of scrap. During operation, the front corner of the hammer's working end face first strikes the leading edge of the paper sheet, creating a groove. Multiple fingers then pull the paper apart. Due to the length of the working end face, the groove rides on the working end face, holding the paper in place. Once the working end face passes, feeding resumes, creating a feed-stop-feed-stop cycle. This effectively prevents large scraps from entering the shredder all at once when roller pressure is lost. The ratio of the finger thickness to the width of the hammer's working end face should be between 1 / 2 and 1 / 5. A ratio greater than 1 / 2 increases bending drag, causing large scraps to enter the shredder all at once. A ratio less than 1 / 5 shortens the life of the fingers. The finger hammers are mounted in eight groups, 180 degrees symmetrically, with one finger staggered to ensure uniform and seamless shredding. If the finger hammer is worn or a small amount of large pieces enter the crusher accidentally, the paper can be discharged in time through the vibrating screen to avoid large pieces and fine powder. At the same time, the possibility of blocking the screen holes is eliminated and fire is prevented. The vibrating screen plays the role of the final safety insurance.

[0009] According to the above structure, a pulp and paper pulverizer is provided, which can produce sheet paper of various specifications, with diameters of 3-6 mm, 20-25 mm, 30-35 mm, 40-45 mm and other specifications, with uniform external dimensions, hand-tear effect, plush on the periphery, no shear hard marks, no fine powder in the finished product, and can prevent screen blockage and fire. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] FIG1 is a front view of the present invention.

[0011] FIG2 is a side view of the present invention, which includes a belt conveyor and a pressure roller, wherein the rotor is divided into multiple groups of evenly spaced and staggered tool holders, and after the hammers are installed, the end faces of the hammers form a seamless circumference.

[0012] FIG3 is a front view of the fixed knife of the present invention.

[0013] FIG4 is a schematic cross-sectional view of the fixed knife of the present invention, which has an arc-shaped working angle.

[0014] FIG5 is an oblique perspective view of the rotor of the pulverizer of the present invention. There are 8 sets of tool holders on the rotor end face and 3 sets in the axial direction. The phase difference of the rotor end face is 15 degrees.

[0015] FIG6 is a disk of the rotor of the pulverizer of the present invention, which is in the shape of giant teeth and has four mounting holes. Hammers have been installed on it, and there are two holes for backup.

[0016] FIG7 is an oblique perspective view of the finger hammer of the pulverizer of the present invention, which has multiple fingers, and the thickness of the finger-like members is smaller than the width of the working end surface of the hammer body.

[0017] FIG8 is an oblique perspective view of the finger hammer of the pulverizer of the present invention, which has only one single finger. DETAILED DESCRIPTION

[0018] The present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments:

[0019] Example 1, as shown in Figures 1 and 2, is a pulp and paper pulverizer comprising a feed port 1, hammers 2, a rotor 3, a screen 9, a screen press frame 5, a discharge port 7, a machine body 8, and a motor 6. The feed port 1 is characterized in that one side is straight and the other side is angled. Below the feed port 1 are two opposing fixed blades 14, each with an arc-shaped working angle. The mounting holes of the fixed blades 14 are waist-shaped, allowing the distance between the fixed blades 14 and the hammers 2 to be adjusted up and down. A pressure roller 13 is located near the top of the fixed blades 14. The pressure roller 13 has a spring to adjust the pressure, and the pressure roller 13 is located near the fixed blades 14. The rotor 3 has a circular disc shaped like a giant tooth, which is divided into eight equal parts. Two sets of tool holders are mounted on each giant tooth. Each tool holder has two holes, for a total of four holes: one set for mounting the hammers 2 and the other set for standby use. In the axial plane of the rotor 3, the rotor 3's tool holders are divided into three groups. In the end plane of the rotor 3, each group of tool holders is spaced 15 degrees apart, allowing the hammers 2 to be arranged at the end face to form a circular shape in the cross-section of the rotor 3. The pulp and paper pulverizer's hammers 2 are finger-shaped hammers 2. Two pinholes 16 are provided at one end of the hammer body 15, which connects to the pulverizer's rotor 3's tool holders via two pins. The other end is a working end face 17. The two corners of working end face 17 are finger-shaped, without sharp corners or edges. It is sintered from tungsten carbide into an ellipsoidal sphere with a rough friction surface. The working end face 17 has a groove in the middle, into which a palm scraper 18 is welded. The front end of palm scraper 18 features uniform fingers 19, with grooves between them. The fingers 19 and the grooves are of equal width. The corners of the fingers 19 are ellipsoidal, without sharp corners or edges. They are made of sintered tungsten carbide and have a rough friction surface. The other end of palm scraper 18 features a mounting groove, which is welded perpendicularly to the groove in the middle of the working end face 17 of the hammer body 15. The thickness of the fingers 19 is less than the width of the hammer body 15, with the ratio of the two being 2:5. The screen 9 is mounted on the screen press frame 5, but a vibration motor 10 is located below the frame. The frame 5 is separated from the machine body 8 by a spring vibration isolation device 20, allowing the connected screen 9 and frame 5 to vibrate independently and simultaneously. The rake hammers 2 and screen 9 are kept at a safe distance, preventing them from colliding.

[0020] Embodiment 2 has the same basic structure as the embodiment shown in Figures 1 and 2, except that a finger hammer 2 is not used. Instead, an ordinary hammer 2 is used which is several times thicker and has a thickness of 4 mm. The hammer is replaced with a hammer isolation ring which is several times thicker and has a width of 4 mm.

[0021] Example 3, whose basic structure is shown in Figures 1 and 2, uses the finger hammer of the crusher of the present invention in Figure 8, wherein by changing the width of a single finger, paper sheets of various large sizes such as 20-25 mm, 30-35 mm, 40-45 mm, etc. can be produced.

[0022] Example 4 has the same basic structure as Figures 1 and 2, but without the screen press 5 and vibrating motor 10. The screen mesh uses a large aperture of 50 mm. Using the finger hammers of the pulverizer of the present invention shown in Figure 8, by varying the width of each finger, paper sheets of various sizes, such as 20-25 mm, 30-35 mm, and 40-45 mm, can be produced. The effect is slightly less impressive, but the cost is lower. Beneficial effects

[0023] When the pulverizer is operating, the circular working angles of the two fixed hammers 14 prevent hard marks from forming on the pulp and paper. All working surfaces of the finger hammers 2 that come into contact with the pulp and paper are finger-shaped, without sharp corners or edges. They are sintered from tungsten carbide into an ellipsoidal sphere with a rough friction surface, creating a hand-torn paper effect, leaving the edges of the small pieces velvety and free of hard marks. The rotor 3 is divided into multiple groups of evenly spaced, staggered toolholders, forming a seamless circumference on the end faces of the hammers 2. This ensures that the tail of the descending paper sheet is always supported by a group of hammers, preventing the tail end of a large piece from suddenly escaping into the pulverizer chamber and causing unevenness in the finished product. The rotational speed of the finger hammers 2 is coordinated with the feed rate of the belt conveyor 11 to control the length of the small paper pieces. The width of the small paper pieces can be controlled by selecting the width of the finger members 19 and the slots, thereby producing pulp and paper of a desired size. Two pin holes 16 are provided at one end of the hammer body 15 to prevent the finger hammers from shaking during operation, ensuring a more uniform distribution of the small paper pieces. The thickness of the finger-shaped member 19 is less than the width of the working end face 17 of the hammer body 15. This is the key technology for achieving intermittent feeding and ensuring uniform crushing of tailings. During operation, the front corner of the working end face 17 of the hammer body 15 first touches the leading edge of the paper sheet. Due to this initial contact, a groove is formed in the paper sheet. Then, multiple fingers 19 tear the paper sheet. At this time, due to the long working end face 17, the paper groove rides on the working end face 17, and the paper sheet is supported. After the working end face 17 passes, feeding begins again, forming a feed-stop, feed-stop working state, effectively preventing large tailings from being fed into the crusher all at once when the pressure of the pressure roller 13 is lost. The ratio of the thickness of the finger-shaped member 19 to the width of the working end face 17 of the hammer body 15 is between 1 / 2 and 1 / 5. When it is greater than 1 / 2, bending drag increases, and large tailings will be fed into the crusher all at once. When it is less than 1 / 5, the service life of the finger-shaped member 19 is short. Through the vibrating screen 9, paper pieces will be discharged in time to avoid large pieces and fine powder. At the same time, the possibility of malfunction of blocking the screen holes is eliminated to prevent fire. The vibrating screen 9 plays the role of the final safety insurance.

[0024] According to the above structure, a pulp and paper shredder is provided, which can produce sheet paper of various specifications, with uniform outer dimensions, hand-tear effect, plush around, no shear marks, no fine powder in the finished product, and can prevent screen blockage and fire, is easy to use and has a long service life.

[0025] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Any simple modification, equivalent change or modification made to the above embodiment based on the technical essence of the present invention shall fall within the scope of the technical solution of the present invention.

Claims

1. A pulp and paper pulverizer, comprising a feed inlet (1), a hammer (2), a rotor (3), a screen (9), a screen pressing frame (13), a discharge port (7), a machine body (8), and a motor (6), characterized in that: Two fixed knives (14) are arranged below the feed port (1), and the disc of the rotor (3) is in the shape of giant teeth, and a knife holder is provided on the giant teeth, so that the front end faces of the hammer pieces (2) can be arranged and connected on the end face of the rotor (3) to form a seamless circular shape. In the axial plane of the rotor (3), the knife holders of the rotor (3) are evenly grouped, and the hammer pieces are finger hammer pieces (2).

2. The pulp and paper pulverizer according to claim 1, characterized in that: One side of the feed inlet (1) is straight, and the other side is in an oblique bucket shape.

3. The pulp and paper pulverizer according to claim 1, characterized in that: Two fixed knives (14) are installed opposite to each other below the feed port (1). The working angle of the fixed knives (14) is in an arc shape. The mounting holes of the fixed knives (14) are waist holes, thereby the distance between the fixed knives and the hammers (2) can be adjusted up and down.

4. The pulp and paper pulverizer according to claim 1, characterized in that: A pressing wheel (13) is arranged above the fixed knife (14), and the pressing wheel (13) has a spring to adjust the pressure.

5. The pulp and paper pulverizer according to claim 1, characterized in that: The disc of the rotor (3) is in the shape of a giant tooth, which is equally divided into 8 parts. Each giant tooth is equipped with 2 sets of tool holders, each set has two holes, a total of 4 holes, one set of holes is used to install the hammer (2), and the other set is a spare hole, which is also used to pull out the pin rod when the adjacent set of hammers is replaced.

6. The pulp and paper shredder according to claim 1, characterized in that: In the axial plane of the rotor (3), the rotor (3) tool holders are evenly divided into more than three groups.

7. The pulp and paper shredder according to claim 1, characterized in that: The hammer piece is a finger hammer piece. One end of the hammer piece mother body (15) is provided with two pin holes (16). The hammer piece mother body is connected to the blade holder of the rotor (3) of the pulverizer by two pin rods passing through the pin holes. The other end is a working end face (17). The two corners of the working end face (17) are finger-shaped, without sharp corners or sharp edges. It is sintered into an elliptical sphere by tungsten carbide and has a rough friction surface. There is a groove in the middle of the working end face (17), and a palm-type scraper (1 8), the front end of the palm scraper (18) has a uniform finger-shaped piece (19), the two corners of the finger-shaped piece (19) are elliptical spherical, without sharp corners and sharp edges, and are sintered by tungsten carbide, with a rough friction surface, uniform grooves between the finger-shaped pieces (19), and the widths of the finger-shaped pieces (19) and the grooves are the same, and the other end of the palm scraper (18) has a mounting groove, which is vertically embedded and welded with the groove in the middle of the working end surface (17) of the hammer mother body (15).

8. The pulp and paper shredder according to claim 1, characterized in that: The thickness of the hammer finger (19) is smaller than the width of the working end surface (17) of the hammer body (15), and the ratio between the two is between 1 / 2 and 1 / 5.

9. The pulp and paper shredder according to claim 1, characterized in that: The screen (9) of the pulp and paper pulverizer is installed on a screen press frame (5), a vibration motor (10) is arranged below the screen press frame (5), and the screen press frame (5) is separated from the machine body (8) by a spring vibration isolation device (20), so that the connected screen (9) and the screen press frame (5) can vibrate independently and simultaneously.

10. The pulp and paper shredder according to claim 1, characterized in that: The finger hammers (2) of the pulp pulverizer are at a safe distance from the screen (9) and will not collide with each other.

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