A screenless filter

Abstract

The present invention provides a screenless filter, belonging to the technical field of screenless filters. It solves the problem that the existing screenless filters have a low recovery rate of molten plastic fluid. This screenless filter includes a box body, the box body is provided with an installation cavity, a first feed inlet, a discharge outlet and a discharge port. A first filter plate and a second filter plate are arranged in the installation cavity. The first filter plate and the second filter plate divide the installation cavity into an independent discharge cavity and a first feed cavity and a second feed cavity respectively located on both sides of the discharge cavity. It also includes a first driving mechanism, a second driving mechanism and a first scraper and a second scraper respectively located in the first feed cavity and the second feed cavity. A first discharge groove and a second discharge groove are formed at the bottom of the box body. A first screw rod and a second screw rod connected to the second driving mechanism are respectively installed on the first discharge groove and the second discharge groove. This screenless filter has the advantages of high recovery efficiency of molten plastic fluid and high waste discharge efficiency of impurities.

Description

Technical Field

[0001] The present invention belongs to the technical field of screenless filters and relates to a screenless filter. Background Art

[0002] In the plastic granulation industry, in order to solve the problem that traditional filters need to frequently replace the filter screen, a kind of screenless filter has emerged on the market. Since this kind of screenless filter can filter the molten plastic mixture without setting a filter screen, it is widely adopted by the market. The existing filter uses a filter plate structure to replace the original filter screen structure. The filter plate is densely provided with filter through-holes. When using the screenless filter to filter the molten plastic mixture for granulation, the filter through-holes intercept the impurities in the molten plastic with a diameter larger than the diameter of the filter through-holes, and the molten plastic fluid that passes through the filter through-holes enters the discharge cavity and is output from the discharge port. In practice, the intercepted impurities need to be discharged, otherwise they will stay on the filter plate or even in the filter through-holes, thus affecting the normal filtering function of the filter plate.

[0003] Currently, the impurity treatment generally directly discharges the impurities at any time through a discharge pipe. For example, in a Chinese patent with the publication number CN206926232U and the name of a filter, the technical solution includes a box body, the box body is provided with an installation cavity, a feed inlet, a discharge outlet and a slag discharge port; a support assembly, the support assembly is fixedly installed in the installation cavity, the support assembly forms a material containing cavity, the discharge outlet is communicated with the material containing cavity, the support assembly is provided with a flow channel, and the flow channel is communicated with the material containing cavity; a first filter plate and a second filter plate, both filter plates are provided with filter through-holes, the first filter plate is fixedly installed on the first side of the support assembly, the second filter plate is fixedly installed on the second side of the support assembly; a first scraper and a second scraper, the blade of the first scraper is attached to the plate surface of the first filter plate, the blade of the second scraper is attached to the plate surface of the second filter plate, and a feed containing cavity is formed between the first filter plate, the second filter plate and the cavity wall of the installation cavity, the feed inlet is communicated with the feed containing cavity, and the slag discharge port is communicated with the feed containing cavity; a driving mechanism, the driving mechanism is connected to the box body, the first scraper and the second scraper are connected to the driving shaft of the driving mechanism and rotate synchronously with the driving shaft. The problem with it is that: since in addition to solid impurities such as metals, the impurities still contain a certain proportion of molten plastic fluid, directly discharging it causes this part of the molten plastic fluid mixed in the impurities not to be filtered and recycled, thus reducing the recovery rate of the molten plastic fluid. Summary of the Invention

[0004] The purpose of the present invention is to solve the above technical problems and propose a screenless filter.

[0005] The object of the present invention can be achieved by the following technical solutions: A screenless filter, comprising a box body, the box body is provided with an installation cavity, a first feed inlet, a discharge outlet and a discharge port, the installation cavity is provided with a first filter plate and a second filter plate, the first filter plate and the second filter plate are provided with filter through holes, the first filter plate and the second filter plate divide the installation cavity into an independent discharge cavity and a first feed cavity and a second feed cavity respectively located on both sides of the discharge cavity, the discharge cavity is located between the first filter plate and the second filter plate and is communicated with the discharge outlet, the first feed cavity and the second feed cavity are both communicated with the second feed inlet, and it is characterized in that: it further comprises a first driving mechanism, a second driving mechanism and a first scraping plate and a second scraping plate respectively located in the first feed cavity and the second feed cavity, the first driving mechanism is installed on the box body and is used for driving the first scraping plate and the second scraping plate to move back and forth up and down along the surfaces of the first filter plate and the second filter plate respectively, a first discharge groove and a second discharge groove are opened at the bottom of the box body, the first discharge groove and the second discharge groove are respectively located at the bottoms of the first feed cavity and the second feed cavity and are respectively communicated with the first feed cavity and the second feed cavity, a first screw rod and a second screw rod connected with the second driving mechanism are respectively installed on the first discharge groove and the second discharge groove, and the first discharge groove and the second discharge groove are communicated with the discharge port.

[0006] In the above-mentioned screenless filter, the box body comprises a base located in the middle and a first side plate and a second side plate respectively located on both sides of the base and hinged to the base, the first feed inlet and the discharge outlet are opened on the base, the first filter plate and the second filter plate are installed on the base, the first filter plate, the base and the first side plate form the first feed cavity, the second filter plate, the base and the second side plate form the second feed cavity, and the first filter plate, the second filter plate and the base form the discharge cavity.

[0007] In the above-mentioned screenless filter, a feed seat is further installed on the base, a first groove is opened on the base and a feed channel is formed between the first groove and the feed seat, the first feed inlet is opened on the feed seat and the first feed inlet is communicated with the feed channel, first guide grooves and second guide grooves are respectively arranged at the upper ends of the first feed cavity and the second feed cavity, the first guide grooves and the second guide grooves are both communicated with the feed channel, and the axial lengths of the openings of the first guide grooves and the second guide grooves are respectively matched with the widths of the first filter plate and the second filter plate.

[0008] In the above-mentioned wire mesh-free filter, a discharge seat is also installed on the base, a second groove is opened on the base and a discharge channel is formed between the second groove and the above-mentioned discharge seat, the above-mentioned discharge port is opened on the discharge seat and the discharge port and the discharge cavity are both connected to the discharge channel.

[0009] In the above-mentioned wire mesh-free filter, a support plate is also provided on the base, and the support plate separates the discharge cavity into a first inner cavity and a second inner cavity. Three first discharge through holes are opened on the support plate, and three second discharge through holes respectively connected with the above-mentioned three first discharge through holes are opened on the discharge channel. The above-mentioned first inner cavity and the second inner cavity are connected with the discharge channel through the above-mentioned three first discharge through holes and the second discharge through holes.

[0010] In the above-mentioned wire mesh-free filter, the first driving mechanism includes a driving plate, a first cylinder base and a first hydraulic cylinder fixedly mounted on the first cylinder base, the first cylinder base is fixedly mounted on the above-mentioned box body through two first guide rods, the driving plate is sleeved on the above-mentioned two first guide rods and can slide up and down along the two first guide rods, four second guide rods are fixedly connected to the driving plate, and the above-mentioned first scraper and second scraper are respectively fixedly connected to two of the above-mentioned four second guide rods.

[0011] In the above-mentioned wire-free filter, the second driving mechanism includes a first driving motor and a second driving motor respectively connected to the above-mentioned first screw and the second screw, and the first driving motor and the second driving motor respectively drive the first screw and the second screw to rotate in opposite directions; or, includes a driving motor and a driving gear shaft and a driven gear shaft respectively fixed to the above-mentioned first screw and the second screw, the driving gear shaft and the driven gear shaft are connected by gear meshing, and the driving gear shaft is connected to the output shaft of the driving motor through a chain.

[0012] In the above-mentioned wire mesh-free filter, a waste valve structure is also provided at the discharge port of the box body, and the waste valve structure includes a valve seat, a partition and a second hydraulic cylinder installed on the valve seat, the valve seat is provided with two first through holes and a blocking channel which is perpendicular to the axis of the above-mentioned two first through holes, the partition is provided with two second through holes which respectively match the above-mentioned two first through holes, the partition is connected to the second hydraulic cylinder and under the drive of the second hydraulic cylinder, the partition can move back and forth on the blocking channel so that the two second through holes are arranged opposite to the above-mentioned two first through holes so that the first through holes are connected to the discharge port, or are completely staggered so that the first through holes are completely isolated from the discharge port.

[0013] In the above-mentioned wire-free filter, a connector is installed in an interference fit at the end of the first through hole far from the discharge port. A through hole communicating with the first through hole is formed in the connector. A flange is formed by radially protruding outward around the end of the connector far from the first through hole. There is a gap between the flange and the valve seat.

[0014] In the above-mentioned wire-free filter, four square grooves are formed on the outer side wall around the flange.

[0015] Compared with the prior art, the present wire-free filter has the following advantages:

[0016] 1. The waste residues such as impurities left after filtration are not directly discharged, but are pushed out and discharged by the rotation of the screw. Since the temperature of the molten plastic mixture is generally relatively high, reaching about 200 °C, the molten plastic that really needs to be recycled is in a liquid fluid state, while impurities such as sand, iron, copper, and aluminum are in a solid state. During the rotation of the screw, since the molten plastic is in a liquid fluid state, the molten plastic will flow back under the rotation and push of the screw, while solid impurities such as sand, iron, copper, and aluminum will be pushed forward, so as to further separate the impurities containing the molten plastic fluid, push the solid impurities such as sand, iron, copper, and aluminum forward to accumulate at the front end of the screw, and the molten plastic fluid will flow back and concentrate at the rear end of the screw. Then, driven by the back-and-forth movement of the scraper, a certain amount of the molten plastic fluid accumulated at the rear end of the screw will be carried to the filter plate for secondary filtration. At the same time, when the molten plastic fluid accumulated at the rear end of the screw accumulates to a certain extent, part of it will overflow to the filter plate for secondary filtration, so as to further filter this part of the molten plastic fluid into the discharge cavity, thereby improving the plastic recovery rate;

[0017] 2. The arrangement of the waste discharge valve structure enables waste materials such as impurities to be discharged regularly rather than at any time. Firstly, impurities and other waste materials will wait for a certain period of time at the discharge port and then be discharged uniformly. Therefore, there is no need to set up a cooling device at the discharge port. During the waiting period, the impurities will cool naturally. Thus, the structure is simplified and the cost is reduced. Secondly, when the screw pushes the impurities towards the discharge port, the impurities in the front are blocked by the partition of the waste discharge valve structure. Under the push of the screw, the molten plastic fluid mixed in the impurities in the front will be pushed by the solid impurities such as sand, iron, copper, and aluminum pushed from the rear. In addition, the front of the molten plastic fluid mixed in the impurities is blocked by the partition and the solid impurities such as sand, iron, copper, and aluminum in the front. The molten plastic fluid mixed in the impurities in the front will be squeezed by the solid impurities such as sand, iron, copper, and aluminum pushed from the rear to both sides of the solid impurities and then to the rear of the solid impurities pushed over. And the solid impurities such as sand, iron, copper, and aluminum pushed from the rear will squeeze towards the partition until they are blocked by the partition or other solid impurities. Therefore, the arrangement of the waste discharge valve structure causes the solid impurities to be continuously squeezed towards the partition, while the molten plastic fluid will be continuously pushed to the rear and get closer to the screw. Combined with the above-mentioned screw structure, the squeezed-back molten plastic fluid is continuously moved towards the rear end of the screw, further improving the plastic recovery rate.

[0018] 3. This filter adopts two groups of filtering and waste discharge structures that are symmetric left and right, improving the filtering and waste discharge efficiency. At the same time, the rotation directions of the first screw and the second screw are opposite, which is equivalent to the forces exerted by the first screw and the second screw on the box body canceling each other out. Thus, the unstable vibration force generated by the rotation of the first screw and the second screw on the box body is avoided, making the box body work more stably. Brief Description of the Drawings

[0019] Figure 1 is the structural schematic diagram of this filter.

[0020] Figure 2 is the partial exploded view of this filter.

[0021] Figure 3 is another structural schematic diagram of this filter.

[0022] Figure 4 is Figure 3 the sectional view at A - A in

[0023] Figure 5 is the partial exploded view of the other side of this filter.

[0024] Figure 6 is the structural schematic diagram of the box body.

[0025] Figure 7 is the partial exploded view of the box body.

[0026] Figure 8 It is a schematic structural view of the base.

[0027] Figure 9 It is a schematic structural view of the waste discharge valve structure.

[0028] In the figure, 1 is the box body; 1a is the first feed inlet; 1b is the discharge outlet; 1c is the discharging port; 1d is the base; 1e is the first side plate; 1f is the second side plate; 2 is the first feed cavity; 3 is the second feed cavity; 4 is the discharge cavity; 41 is the first inner cavity; 42 is the second inner cavity; 5 is the first filter plate; 6 is the second filter plate; 7 is the feed seat; 8 is the feed channel; 9 is the first guide chute; 10 is the second guide chute; 11 is the discharge seat; 12 is the discharge channel; 12a is the second discharge through hole; 13 is the support plate; 13a is the first discharge through hole; 14 is the first hydraulic cylinder; 15 is the first cylinder base; 16 is the first guide rod; 17 is the driving plate; 18 is the second guide rod; 19 is the first driving motor; 20 is the second driving motor; 21 is the valve seat; 21a is the first through hole; 22 is the partition plate; 22a is the second through hole; 23 is the second hydraulic cylinder; 24 is the connector; 25 is the convex edge; 26 is the square groove; 27 is the first scraper; 28 is the second scraper; 29 is the first discharge chute; 30 is the second discharge chute; 31 is the first screw rod; 32 is the second screw rod. Detailed implementation manners

[0029] The following are specific embodiments of the present invention and in combination with the accompanying drawings, the technical solutions of the present invention are further described, but the present invention is not limited to these embodiments.

[0030] As Figure 1 , 2 , 3, and 4 show, this non-wire mesh filter includes a box body 1. The box body 1 is provided with an installation cavity, a first feed inlet 1a, a discharge outlet 1b, and a discharging port 1c. A first filter plate 5 and a second filter plate 6 are provided in the installation cavity. The first filter plate 5 and the second filter plate 6 are provided with filter through holes. The filter through holes are micro holes with a diameter of 0.2 mm and are uniformly distributed over the entire first filter plate 5 and the second filter plate 6. Among them, the box body 1 includes a base 1d located in the middle and a first side plate 1e and a second side plate 1f respectively located on both sides of the base 1d and hinged to the base 1d. The first feed inlet 1a and the discharge outlet 1b are opened on both sides of the base 1d. The first filter plate 5 and the second filter plate 6 are installed on the base 1d. The first filter plate 5, the base 1d, and the first side plate 1e form the first feed cavity 2. The second filter plate 6, the base 1d, and the second side plate 1f form the second feed cavity 3. The first filter plate 5, the second filter plate 6, and the base 1d form the discharge cavity 4. The hinged connection between the first side plate 1e and the second side plate 1f and the base 1d makes the maintenance more convenient. When it is necessary to repair the internal structure, for example, when inspecting the first filter plate 5 or the second filter plate 6, only need to open the first side plate 1e or the second side plate 1f.

[0031] Further, as shown in Figure 2 , 4 , 6 and 8, a feeding base 7 is further installed on the base 1d. A groove is formed on the base 1d, and a feeding channel 8 is formed between the groove and the feeding base 7. The first feeding port 1a is opened on the feeding base 7 and the first feeding port 1a communicates with the feeding channel 8. First guiding grooves 9 and second guiding grooves 10 are respectively arranged at the upper ends of the first feeding cavity 2 and the second feeding cavity 3. Both the first guiding groove 9 and the second guiding groove 10 communicate with the feeding channel 8. The axial lengths of the openings of the first guiding groove 9 and the second guiding groove 10 respectively match the widths of the first filter plate 5 and the second filter plate 6.

[0032] Further, as shown in Figure 2 , 4 , 5 and 7, a discharging base 11 is further installed on the base 1d. A groove is formed on the base 1d, and a discharging channel 12 is formed between the groove and the discharging base 11. The discharging port 1b is opened on the discharging base 11, and both the discharging port 1b and the discharging cavity 4 communicate with the discharging channel 12. A supporting plate 13 is further arranged on the base 1d. The supporting plate 13 divides the discharging cavity 4 into a first inner cavity 41 and a second inner cavity 42. Three first discharging through holes 13a are formed on the supporting plate 13, and three second discharging through holes 12a respectively communicating with the three first discharging through holes 13a are formed on the discharging channel 12. The first inner cavity 41 and the second inner cavity 42 communicate with the discharging channel 12 through the three first discharging through holes 13a and the second discharging through holes 12a. A heating device is installed above the base 1d to continue heating the molten plastic mixture entering the first guiding groove 9 and the second guiding groove 10, so as to prevent the plastic fluid in the molten plastic mixture from becoming solid due to temperature drop. The supporting plate 13 is an integral structure with the upper end of the base 1d, and the supporting plate 13 can well transfer the heat generated by the heating device at the upper end of the base 1d to the entire discharging cavity 4 to heat the filtered plastic fluid, so as to prevent the filtered plastic fluid from becoming solid and blocking the discharging due to temperature reduction.

[0033] As shown in Figure 1 , 2 , 3 and 4, this filter further includes a first driving mechanism, a second driving mechanism, a waste discharging valve structure, and a first scraper 27 and a second scraper 28 respectively located in the first feeding cavity 2 and the second feeding cavity 3.

[0034] Among them, the first driving mechanism includes a driving plate 17, a first cylinder base 15, and a first hydraulic cylinder 14 fixedly installed on the first cylinder base 15. The first cylinder base 15 is fixedly installed on the box body 1 through two first guide rods 16. The driving plate 17 is sleeved on the two first guide rods 16 and can slide up and down along the two first guide rods 16. Four second guide rods 18 are fixedly connected to the driving plate 17. The first scraper 27 and the second scraper 28 are respectively fixedly connected to two of the four second guide rods 18. The first hydraulic cylinder 14 works to drive the two scrapers to move back and forth up and down along the surfaces of the first filter plate 5 and the second filter plate 6 respectively.

[0035] Further, as shown in Figure 2 , 4 and 7, a first discharge groove 29 and a second discharge groove 30 are opened at the bottom of the box body 1. The first discharge groove 29 and the second discharge groove 30 are respectively located at the bottoms of the first feeding cavity 2 and the second feeding cavity 3 and are respectively communicated with the first feeding cavity 2 and the second feeding cavity 3. The axial lengths of the openings of the first discharge groove 29 and the second discharge groove 30 respectively match the first filter plate 5 and the second filter plate 6. A first screw 31 and a second screw 32 are respectively installed on the first discharge groove 29 and the second discharge groove 30. The first discharge groove 29 and the second discharge groove 30 are communicated with the discharge port 1c. The second driving mechanism includes a first driving motor 19 and a second driving motor 20 respectively connected to the first screw 31 and the second screw 32. The first driving motor 19 and the second driving motor 20 respectively drive the first screw 31 and the second screw 32 to rotate in opposite directions. In addition to the above structure, the second driving mechanism can also be a structure including a driving motor, a driving gear shaft and a driven gear shaft respectively fixedly connected to the first screw 31 and the second screw 32. The driving gear shaft and the driven gear shaft are connected by gear meshing. The driving gear shaft is connected to the output shaft of the driving motor through a chain. A major advantage of this structural design is that only one driving source is required for driving, which simplifies the structure and thus reduces the cost. At the same time, the rotation directions of the first screw 31 and the second screw 32 are controlled to be opposite. The rotation directions of the first screw 31 and the second screw 32 are opposite, which is equivalent to the forces exerted by the first screw 31 and the second screw 32 on the box body 1 canceling each other out, thereby avoiding the unstable vibration force generated by the rotation of the first screw 31 and the second screw 32 on the box body 1 and making the box body 1 work more stably.

[0036] Among them, as shown in Figure 1 , 2As shown in Figure 9, the waste valve structure is arranged at the discharge port 1c, including a valve seat 21, a partition 22 and a second hydraulic cylinder 23 installed on the valve seat 21, the valve seat 21 is provided with two first through holes 21a and a blocking channel which is perpendicular to the axis of the two first through holes 21a, the partition 22 is provided with two second through holes 22a which respectively match the two first through holes 21a, the partition 22 is connected to the second hydraulic cylinder 23 and under the drive of the second hydraulic cylinder 23, the partition 22 can move back and forth on the blocking channel so that the two second through holes 22a are arranged opposite to the two first through holes 21a so that the first through holes 21a are connected to the discharge port 1c, or are completely staggered so that the first through holes 21a are completely isolated from the discharge port 1c.

[0037] Furthermore, a connector 24 is installed on the end of the first through hole 21a away from the discharge port 1c by interference fit, and a through hole connected to the first through hole 21a is opened on the connector 24. The end of the connector 24 away from the first through hole 21a is radially protruded to the outside to form a convex edge 25, and there is a gap between the convex edge 25 and the valve seat 21. The setting of the convex edge 25 and the gap facilitates the connection of the first through hole 21a with an external collection device, and discharges impurities and other waste residues to the collection device for unified collection and treatment to avoid environmental pollution. For example, for a garbage sack, the bag mouth of the garbage sack is directly put on the convex edge 25, and the bag mouth is tied in the gap to prevent slipping. Four square grooves 26 are opened on the outer wall around the convex edge 25. The setting of the square grooves 26 is also for the convenience of connection with an external collection device. For example, the collection device is equipped with a connector 24 matching the convex edge 25 and the square groove 26, which can be directly connected, which is very convenient.

[0038] During operation, the molten plastic mixture enters from the first feed inlet 1a, passes through the feed channel 8 in sequence and then divides into two parts to enter the first feed tank and the second feed tank respectively, and flows onto the surfaces of the first filter plate 5 and the second filter plate 6 along the notches of the first feed tank and the second feed tank respectively. Since the air in the first feed chamber 2 and the second feed chamber 3 is heated by the high-temperature molten plastic mixture to form a high air pressure, and the discharge chamber 4 is connected to the outside and the air pressure is lower than that of the first feed chamber 2 and the second feed chamber 3. Under the action of the air pressure difference, most of the molten plastic fluid with a diameter smaller than the diameter of the filter through-holes on the first filter plate 5 and the second filter plate 6 enters the discharge chamber 4 through the filter through-holes, and then passes through the first discharge through-hole 13a on the support plate 13, the second discharge through-hole 12a on the discharge channel 12 and the discharge channel 12 to be output and recycled from the discharge port 1b. Solid impurities such as sand, iron, copper, and aluminum with a diameter larger than the filter through-holes and a small part of the molten plastic fluid are blocked and retained on the surfaces of the first filter plate 5 and the second filter plate 6. When waste needs to be discharged, the first hydraulic cylinder 14 drives the first scraper 27 and the second scraper 28 to move downward to scrape the impurities and a small part of the molten plastic fluid mixture on the first filter plate 5 and the second filter plate 6 into the first discharge tank 29 and the second discharge tank 30 respectively. Then the first driving motor 19 and the second driving motor 20 work to drive the first screw 31 and the second screw 32 to rotate respectively. When the screw rotates, since the molten plastic is in a liquid fluid state, the molten plastic will flow back under the rotation and push of the screw, while solid impurities such as sand, iron, copper, and aluminum will be pushed forward, so as to further separate the impurities containing the molten plastic fluid, push the solid impurities such as sand, iron, copper, and aluminum forward to accumulate at the front end of the screw, and the molten plastic fluid therein will flow back and concentrate at the rear end of the screw. Then, driven by the back-and-forth movement of the scraper, a certain amount of the molten plastic fluid accumulated at the rear end of the screw will be carried back to the filter plate for secondary filtration. At the same time, when the molten plastic fluid accumulated at the rear end of the screw accumulates to a certain extent, it will also partially overflow directly onto the filter plate for secondary filtration, so as to further filter and recycle this part of the molten plastic fluid into the discharge chamber 4 to improve the plastic recovery rate.

[0039] During the filtration process, the partition plate 22 on the waste discharge valve is normally closed. That is, the second through hole 22a on the partition plate 22 of the waste discharge valve structure and the first through hole 21a on the valve seat 21 are completely staggered under normal conditions, that is, the first through hole 21a is completely closed. In this way, the mixture of impurities pushed forward by the screw and a small part of the molten plastic fluid is blocked by the partition plate 22. The benefits of being normally closed are as follows: First, the waste materials such as impurities will wait for a certain time at the discharge port 1c and then be discharged regularly. Therefore, there is no need to set a cooling device at the discharge port 1c. During the waiting time, the impurities will cool naturally. Therefore, the structure is simplified and the cost is reduced. Second, when the screw pushes the impurities towards the discharge port 1c, the impurities in the front are blocked by the partition plate 22 of the waste discharge valve structure. Under the push of the screw, the molten plastic fluid mixed in the impurities in the front will be pushed by the solid impurities such as sand, iron, copper, and aluminum pushed from the back. In addition, the front of the molten plastic fluid mixed in the impurities is blocked by the partition plate 22 and the solid impurities such as sand, iron, copper, and aluminum in the front. Therefore, the molten plastic fluid mixed in the impurities in the front will be squeezed by the solid impurities such as sand, iron, copper, and aluminum pushed from the back to both sides of the solid impurities and behind the solid impurities pushed over. And the solid impurities such as sand, iron, copper, and aluminum pushed from the back will be squeezed towards the partition plate 22 until they are blocked by the partition plate 22 or other solid impurities. Therefore, the setting of the waste discharge valve structure makes the solid impurities be continuously squeezed towards the partition plate 22, so that the solid impurities are concentrated and collected and piled up against the partition plate 22, while the molten plastic fluid will be continuously pushed to the back and get closer to the screw. Combining the above screw structure to continuously move the squeezed-back molten plastic fluid towards the rear end of the screw for secondary filtration and recovery further improves the plastic recovery rate. After filtering for a period of time, the partition plate 22 is opened to remove the front impurities close to the partition plate 22. At this time, the removed impurities are basically solid impurities.

[0040] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Those skilled in the art to which the present invention pertains can make various modifications or supplements to the described specific embodiments or use similar methods for substitution, but will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

[0041] Although this text uses many terms such as the box body 1, the first feed inlet 1a, the discharge outlet 1b, the discharge port 1c, the base 1d, the first side plate 1e, the second side plate 1f, the first feed cavity 2, the second feed cavity 3, the discharge cavity 4, the first inner cavity 41, the second inner cavity 42, the first filter plate 5, the second filter plate 6, the feed seat 7, the feed channel 8, the first guide chute 9, the second guide chute 10, the discharge seat 11, the discharge channel 12, the second discharge through hole 12a, the support plate 13, the first discharge through hole 13a, the first hydraulic cylinder 14, the first cylinder base 15, the first guide rod 16, the drive plate 17, the second guide rod 18, the first drive motor 19, the second drive motor 20, the valve seat 21, the first through hole 21a, the partition plate 22, the second through hole 22a, the second hydraulic cylinder 23, the connector 24, the flange 25, the square groove 26, the first scraper 27, the second scraper 28, the first discharge chute 29, the second discharge chute 30, the first screw 31, the second screw 32, etc. more frequently, it does not exclude the possibility of using other terms. The use of these terms is only for more convenient description and explanation of the essence of the present invention; interpreting them as any additional limitation is contrary to the spirit of the present invention.

Claims

1. A screenless filter, comprising a box body (1), the box body (1) being provided with an installation cavity, a first feed inlet (1a), a discharge outlet (1b) and a discharge port (1c), a first filter plate (5) and a second filter plate (6) being arranged in the installation cavity, the first filter plate (5) and the second filter plate (6) being provided with filter through holes, the first filter plate (5) and the second filter plate (6) separating the installation cavity into an independent discharge cavity (4) and a first feed cavity (2) and a second feed cavity (3) respectively located on both sides of the discharge cavity (4), the discharge cavity (4) being located between the first filter plate (5) and the second filter plate (6) and communicating with the discharge outlet (1b), the first feed cavity (2) and the second feed cavity (3) both communicating with a second feed inlet, characterized in that: it further comprises a first driving mechanism, a second driving mechanism and a first scraper (27) and a second scraper (28) respectively located in the first feed cavity (2) and the second feed cavity (3), the first driving mechanism being installed on the box body (1) for driving the first scraper (27) and the second scraper (28) to move back and forth up and down along the surfaces of the first filter plate (5) and the second filter plate (6) respectively, a first discharge groove (29) and a second discharge groove (30) being formed at the bottom of the box body (1), the first discharge groove (29) and the second discharge groove (30) being respectively located at the bottoms of the first feed cavity (2) and the second feed cavity (3) and communicating with the first feed cavity (2) and the second feed cavity (3) respectively, a first screw rod (31) and a second screw rod (32) connected to the second driving mechanism being respectively installed on the first discharge groove (29) and the second discharge groove (30), the first discharge groove (29) and the second discharge groove (30) communicating with the discharge port (1c), the second driving mechanism driving the first screw rod (31) and the second screw rod (32) to rotate in opposite directions, and a waste discharge valve structure being arranged at the discharge port (1c), the waste discharge valve structure comprising a valve seat (21), a partition plate (22) and a second hydraulic cylinder (23) installed on the valve seat (21), two first through holes (21a) and a blocking channel perpendicular to the axis lines of the two first through holes (21a) being formed on the valve seat (21), two second through holes (22a) respectively matching the two first through holes (21a) being formed on the partition plate (22), the partition plate (22) being connected to the second hydraulic cylinder (23), and the partition plate (22) blocking impurities and promoting the reflux of molten plastic for secondary filtration and recovery in the closed state.

2. A screenless filter according to claim 1, characterized in that, The described box body (1) includes a base (1d) located in the middle, and a first side plate (1e) and a second side plate (1f) respectively located on both sides of the base (1d) and hinged to the base (1d). The first feed inlet (1a) and the discharge outlet (1b) are opened on the base (1d). The first filter plate (5) and the second filter plate (6) are installed on the base (1d). The first filter plate (5), the base (1d) and the first side plate (1e) form the above-mentioned first feed cavity (2). The second filter plate (6), the base (1d) and the second side plate (1f) form the above-mentioned second feed cavity (3). The first filter plate (5), the second filter plate (6) and the base (1d) form the above-mentioned discharge cavity (4).

3. A non-screen filter according to claim 2, wherein, a feed seat (7) is further installed on the base (1d). A first groove is formed on the base (1d), and a feed channel (8) is formed between the first groove and the feed seat (7). The first feed inlet (1a) is opened on the feed seat (7), and the first feed inlet (1a) is communicated with the feed channel (8). First guide grooves (9) and second guide grooves (10) are respectively provided at the upper ends of the first feed cavity (2) and the second feed cavity (3). Both the first guide groove (9) and the second guide groove (10) are communicated with the feed channel (8). The axial lengths of the openings of the first guide groove (9) and the second guide groove (10) respectively match the widths of the first filter plate (5) and the second filter plate (6).

4. A non-screen filter according to claim 2 or 3, wherein, a discharge seat (11) is further installed on the base (1d). A second groove is formed on the base (1d), and a discharge channel (12) is formed between the second groove and the discharge seat (11). The discharge outlet (1b) is opened on the discharge seat (11), and both the discharge outlet (1b) and the discharge cavity (4) are communicated with the discharge channel (12).

5. A non-screen filter according to claim 4, wherein, a support plate (13) is further provided on the base (1d). The support plate (13) divides the discharge cavity (4) into a first inner cavity (41) and a second inner cavity (42). Three first discharge through holes (13a) are formed on the support plate (13). Three second discharge through holes (12a) respectively communicated with the three first discharge through holes (13a) are formed on the discharge channel (12). The first inner cavity (41) and the second inner cavity (42) are communicated with the discharge channel (12) through the three first discharge through holes (13a) and the second discharge through holes (12a).

6. A non-screen filter according to claim 4, wherein, The first driving mechanism comprises a driving plate (17), a first cylinder base (15) and a first hydraulic cylinder (14) fixedly mounted on the first cylinder base (15); the first cylinder base (15) is fixedly mounted on the box (1) via two first guide rods (16); the driving plate (17) is sleeved on the two first guide rods (16) and can slide up and down along the two first guide rods (16); four second guide rods (18) are fixedly connected to the driving plate (17); and the first scraper (27) and the second scraper (28) are respectively fixedly connected to two of the four second guide rods (18).

7. A wire-free filter according to claim 4, It is characterized in that Driven by the second hydraulic cylinder (23), the partition plate (22) can move back and forth on the blocking channel so that the two second through holes (22a) are arranged opposite to the two first through holes (21a) so that the first through holes (21a) and the discharge port (1c) are connected, or are completely offset so that the first through holes (21a) and the discharge port (1c) are completely isolated.

8. A wire-free filter according to claim 7, It is characterized in that A connector (24) is installed with an interference fit on the end of the first through hole (21a) away from the discharge port (1c); a through hole connected to the first through hole (21a) is formed on the connector (24); and a convex edge (25) is formed on the end of the connector (24) away from the first through hole (21a) in a radial direction outwardly protruding, and a gap is formed between the convex edge (25) and the valve seat (21).

9. A wire-free filter according to claim 8, It is characterized in that Four square grooves (26) are formed on the outer side walls around the convex edge (25).

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