Vibration screener

Abstract

As a vibrating screener (1) suitable for pharmaceutical and food processing, the screen carrier frame (10) having an inner circumference (11) and an outer circumference (12); a screen (20) for separating solid particles that extends horizontally within the screen carrier frame (10) and is vertically supported by the screen carrier frame (10); one or more vibration motors (30) disposed on the outer circumference (12) of the screen carrier frame (10) and configured to generate a vibration component in a direction (z) perpendicular to the screen (20); and at least two inner annular discs (14.1, 14.2, 14.3), each having an inner rim and an outer rim, wherein each of the at least two inner annular discs (14.1, 14.2, 14.3) is attached to the inner circumference (11) of the screen carrier frame (10) by its outer rim, and the at least two inner annular discs (14.1, 14.2, 14.3) are parallel It includes at least two inner annular discs (14.1, 14.2, 14.3) spaced apart from each other in a plane; and an inner sleeve (17) disposed within a screen carrier frame (10). The inner sleeve (17) is attached to the inner rims of two of the at least two inner annular discs (14.2, 14.3), wherein the upper inner annular disc (14.2) of the two inner annular discs (14.2, 14.3) and the inner sleeve (17) provide an unbroken surface, while the lower inner annular disc (14.3) of the two inner annular discs is provided with an opening (18) facing the external environment. The device (1) is capable of handling high throughput and meets the highest hygiene standards.

Description

Technology Field

[0001] The present invention relates to a vibrating screener used for separating solid particles, particularly in applications such as pharmaceutical and food processing. However, it is also generally applicable to broader applications such as mineral processing, dehydration, wastewater treatment, quarrying, etc. Background Technology

[0002] Conventional vibrating screeners generally include a screen carrier frame that carries a screen for separating solid particles. The screen extends horizontally within the screen carrier frame and is supported vertically by the screen carrier frame. A vibrating screener of this type is known in Patent Document 1 below. This vibrating screener has a vibration means comprising a conventional electric motor attached to the frame and driving a shaft via a belt. The shaft is located in the center of the frame. An eccentric weight is mounted at each end of the shaft, and the eccentric weight induces orbital oscillatory vibration in the system when the shaft rotates at high speed. Another vibrating screener comprising a conventional electric motor and belt drive is known in Patent Document 2 below. Additionally, a vibrating screener comprising a vibration motor is known in Patent Document 3 below. In other types of vibrating screeners, vibration of the screen carrier frame is typically generated by two vibration motors positioned facing each other on the outer circumference of the screen carrier frame. One advantage of vibration motors is that they are mounted directly onto the screen carrier frame, avoiding additional transmissions, gear trains, couplings, and other moving mechanical parts that require lubrication and can contaminate the device environment with lubricant; this can be a significant issue, particularly in the pharmaceutical and food processing industries.

[0003] delete

[0004] Vibration motors generate vibrations through the rotation of an eccentric weight mounted on a rotatable shaft. Using two counter-rotating vibration motors can generate induced vibrations. When mounted on a screen carrier frame, the vibration motors generate not only a force component in the vertical direction (i.e., up and down) but also force components directed toward or away from each other. In particular, forces directed toward and away from each other act on the screen carrier frame. That is, whenever the vibration motor rotates, radial forces tend to expand and compress the screen carrier frame radially. This breathing can be observed not only with a single vibration motor but also with a larger number of vibration motors due to the inertial mass of the frame. As greater screening forces are required in the vertical direction, the radial forces acting on the screen carrier frame also increase, leading to corresponding breathing and material fatigue of the screen carrier frame. Due to material fatigue, small cracks may develop on the frame or welds.

[0005] High stability of the screen carrier frame can be achieved by using thicker materials or hollow profiles for the screen carrier frame.

[0006] However, the heavier the frame, the more powerful the vibration motor is required to generate vertical screening force, which increases the radial force. Ultimately, this means a very heavy structure that consumes a significant amount of energy during operation.

[0007] While the use of hollow profiles reduces weight, it poses a significant problem for hygienic reasons. Capillary ruptures can occur during the operation of vibrating screeners, although this does not necessarily impede safe operation. However, bacteria can thrive in these small cracks and invade the empty spaces within the hollow profiles. Since disinfectants cannot reach these empty spaces during cleaning, it is nearly impossible to remove bacteria once they have entered. In the worst-case scenario, bacteria such as Salmonella can spread throughout the entire production line, making it difficult even to identify the source. In the pharmaceutical and food processing industries, the only option is often to discard the entire unit. Prior art literature

[65535] 1. UK Published Patent Application No. 2073054 2. Chinese Published Patent Application No. 108421696 3. European Published Patent Application No. 3549683

[0008] Against this backdrop, the present invention aims to increase the material throughput of a vibrating screener while providing a lightweight structure and maintaining high hygiene and safety standards.

[0009] These technical problems are solved by a vibration screener comprising the features of claim 1.

[0010] The vibration screener of the present invention comprises: a screen carrier frame having an inner circumference and an outer circumference; a screen for separating solid particles that extends horizontally within the screen carrier frame and is vertically supported by the screen carrier frame; one or more vibration motors disposed on the outer circumference of the screen carrier frame and configured to generate a vibration component in a direction (z) perpendicular to the screen; at least two inner annular discs, each having an inner rim and an outer rim, wherein each of the at least two inner annular discs is attached to the inner circumference of the screen carrier frame by its outer rim, and the at least two inner annular discs are spaced apart from each other in a parallel plane; and an inner sleeve disposed within the screen carrier frame and attached to the inner rims of the at least two inner annular discs, wherein the upper inner annular disc of the two inner annular discs and the inner sleeve provide an unbroken surface, while the lower inner annular disc of the two inner annular discs is provided with an opening toward the external environment.

[0011] This results in a lightweight structure that allows the device to be driven by a relatively small vibration motor. At least two internal annular discs and an internal sleeve reinforce the screen carrier frame in the space between the two vibration motors, reducing the risk of breathing and capillary cracking of the screen carrier frame.

[0012] Furthermore, the above structure contains no enclosed empty spaces. Therefore, it is possible to reliably prevent the creation of an environment where bacteria can proliferate. All surfaces of the vibrating screener are conveniently accessible for cleaning and disinfection. Cleaning agents and disinfectants can reach all sides of the inner annular disc and inner sleeve through the opening of the lowest inner annular disc. Thus, the device meets the highest hygiene and safety standards.

[0013] Advantageous embodiments of the present invention are set forth in the additional claims.

[0014] In one embodiment of the present invention, the screen carrier frame has a substantially cylindrical shape, thereby avoiding corners and facilitating cleaning and disinfection.

[0015] In another embodiment of the present invention, the outer circumference diameter of the screen carrier frame is greater than 800 mm to allow for a high throughput of the product to be screened.

[0016] In another embodiment of the present invention, the outer rims of at least two inner annular discs are welded to the inner circumference of the screen carrier frame to keep the overall configuration very simple.

[0017] In addition, the inner sleeve can be welded to the inner rim of the two inner annular discs.

[0018] In another embodiment of the present invention, the at least two inner annular disks include first, second, and third inner annular disks, wherein the diameter of the inner rim of the uppermost portion of the first, second, and third inner annular disks is larger than the diameter of the inner rim of the two additional inner annular disks.

[0019] In another embodiment of the present invention, a plurality of webs extend inward from the inner circumference of a screen carrier frame and perpendicularly to at least two inner annular disks, and the webs are connected to the inner circumference of the screen carrier frame and at least one of the inner annular disks. This can further increase the radial rigidity of the screen carrier frame.

[0020] In particular, at least two of the above webs are arranged parallel to each other on the inner circumference opposite to one vibration motor on the outer circumference, thereby further increasing the radial stiffness of the screen carrier frame, particularly in the direction of the radial force generated by the vibration motor.

[0021] In another embodiment of the present invention, each vibration motor has a rotation axis that operates in a tangential plane of the outer circumference of the screen carrier frame, and the tangential planes of the vibration motors are parallel to each other. By tilting the rotation axis, the screening force can be adjusted as needed.

[0022] Preferably, the axis of rotation of the tangential plane is inclined symmetrically with respect to the vertical axis of the vibration screener.

[0023] In another embodiment of the present invention, the vibration motor is attached to the outer circumference of the screen carrier frame by a bracket that is fixed to the outer circumference of the screen carrier frame. This simplifies the adjustment of the rotational axis orientation of the vibration motor.

[0024] In another embodiment of the present invention, the vibrating screener includes a spring assembly that vertically supports the screen carrier frame against a machine base or base plate.

[0025] The vibrating screener may additionally include a hood that seals and covers the screen carrier frame. In this case, the screen is fixed between the upper rim of the screen carrier frame and the lower rim of the hood by means of fixing means.

[0026] Additionally, the discharge hopper can be fixed between the screen and the upper rim of the screen carrier frame. Brief explanation of the drawing

[0027] The present invention will be described in more detail below with reference to the attached drawings. FIG. 1 is a three-dimensional drawing of a vibration screener according to a possible embodiment of the present invention. Figure 2 is a side cross-sectional view of the vibration screener of Figure 1. Figure 3 is a plan view of the vibration screener of Figure 1. Figure 4 is an equiangular view of the screen carrier frame and the vibration motor of the vibration screener of Figure 1. Figure 5 is a cross-sectional view of the structure shown in Figure 3. Specific details for implementing the invention

[0028] FIGS. 1 to 5 show embodiments of a vibrating screen device (1) according to the present invention.

[0029] This vibrating screen device (1) includes a screen carrier frame (10), a screen (20) for separating solid particles, one or more vibrating motors (30), a hood (40), a discharge hopper (50), a fixing means (60), and a spring arrangement (70).

[0030] The screen carrier frame (10) may have a substantial cylindrical shape having an inner circumference (11) and an outer circumference (12). It may be made of metal sheet, preferably stainless steel, by forming a round sleeve and welding the ends together. However, non-circular shapes (e.g., a rectangular shape of the screen carrier frame (10)) may also be considered.

[0031] A screen (20) for separating solid particles is vertically supported by a screen carrier frame (10) and extends horizontally (x, y) within the screen carrier frame (10). In the illustrated embodiment, the screen (20) may include a wire mesh (21) mounted on a perforated support plate (22) which is ultimately supported by the upper rim (13) of the screen carrier frame (10). The screen (20) is removable from the screen carrier frame (10) and is secured by a fixing means (60) positioned on the outer circumference (12) of the screen carrier frame (10).

[0032] In the illustrated embodiment, the vibration force is generated by two vibration motors (30) positioned facing each other on the outer circumference (12) of the screen carrier frame (10). However, the number of vibration motors (30) may be less than two (meaning a single vibration motor) or more than two. The vibration motors (30) are positioned and configured to generate a vibration component in the z-direction perpendicular to the screen (20). It is preferable that each vibration motor (30) includes an eccentric weight mounted on a rotatable shaft. The vibration motors (30) are operated in a reverse rotational manner to generate induced vibrations that include a radial component in the xy plane of the screen (20) in addition to a vertical component in the z-direction (i.e., up and down).

[0033] As shown in FIG. 4, the rotation axis (A) of each vibration motor (30) extends to the tangential plane of the outer circumference (12) of the screen carrier frame (10), whereas the tangential planes of the two vibration motors (30) are parallel to each other. By tilting the rotation axis (A) of the vibration motor (30) with respect to the vertical axis (V) of the vibration screener (1), it is possible to adjust the radial and vertical components of the vibration force.

[0034] In the illustrated embodiment, the axis (A) of the tangential plane is symmetrically inclined with respect to the vertical axis (V) of the vibration screener (1), so that whenever the vibration motor (30) rotates, the vertical components are added together while the radial components are canceled out.

[0035] As previously mentioned, the vibration motor (30) is positioned on the outer circumference (12) of the screen carrier frame (10). It may be mounted directly on the outer circumference (12) or, as illustrated, mounted by a bracket (31) fixed to the outer circumference (12) of the screen carrier frame (10), for example, by welding. The vibration motor (30) may be screw-coupled to the bracket (31), each having a mounting plate (32) for the vibration motor (30). The mounting plate (32) is spaced apart from the outer circumference (12) of the screen carrier frame (10). Optionally, an adjustment mechanism may be provided between the vibration motor (30) and the bracket (31) to facilitate adjustment of the rotation axis (A).

[0036] To reduce or prevent breathing (i.e., elastic deformation) of the screen carrier frame (20) under the radial force component of the vibration motor (30), the screen carrier frame (10) is provided with a special internal reinforcement structure.

[0037] This reinforcing structure includes at least two inner annular discs. In an exemplary embodiment illustrated in the drawing, the reinforcing structure includes first, second, and third inner annular discs (14.1, 14.2, and 14.3), each having an inner rim (15.1, 15.2, and 15.3) and an outer rim (16.1, 16.2, and 16.3), wherein each of the first, second, and third inner annular discs (14.1, 14.2, and 14.3) is attached to the inner circumference (11) of the screen carrier frame (10) by the outer rim (16.1, 16.2, and 16.3), preferably by welding. These welds extend along the entire outer rim (16.1, 16.2 and 16.3) to prevent any gap between the inner annular disk (14.1, 14.2 and 14.3) and the inner circumference (11).

[0038] The first, second, and third inner annular disks (14.1, 14.2, and 14.3) are spaced apart from each other in parallel planes, which are preferably horizontal planes. In the illustrated embodiment, the first inner annular disk (14.1) is positioned parallel to the second inner annular disk (14.2), and the latter is positioned on and parallel to the third inner annular disk (14.3).

[0039] The reinforcing structure further includes an inner sleeve (17) disposed within the screen carrier frame (10) and attached to the inner rims (15.2 and 15.3) of two of the first, second, and third inner annular disks (here, the second and third inner annular disks (14.2 and 14.3)).

[0040] The inner sleeve (17) is substantially cylindrical in shape and preferably connected to the inner rim (15.2, 15.3) through annular welding.

[0041] As illustrated in FIGS. 2, 4 and 5, the upper inner annular disk (14.2) and the inner sleeve (17) of the two inner annular disks connected to the inner sleeve (17) provide an unbroken surface, i.e., a surface without any openings, whereas the lower inner annular disk (14.3) is provided with an opening (18) facing the external environment, preferably downward. The two inner annular disks (14.2 and 14.3), the screen carrier frame (10), and the inner sleeve (17) together with a single first inner annular disk (14.1) form an annular channel (18a) having a box-shaped cross section that substantially increases the radial rigidity of the screen carrier frame (10).

[0042] However, in some cases, the first inner annular disk (14.1) may be omitted. In some other cases, the first inner annular disk (14.1) may be replaced by a second circular channel (18a) having a box-shaped cross section, resulting in a total of four inner annular disks.

[0043] The opening (18) is large enough for cleaning and disinfection purposes, so that the proliferation of bacteria within the circular channel (18a) can be prevented by cleaning the circular channel (18a) using a cleaning agent and / or a disinfectant.

[0044] Optionally, a plurality of webs (19a, 19b) may be provided between the screen carrier frame (10) and the inner annular disks (14.1, 14.2 and 14.3). The webs (19a, 19b) may extend inward from the inner circumference (11) of the screen carrier frame (10) and perpendicularly to the inner annular disks (14.1, 14.2 and 14.3). In particular, the webs (19a, 19b) may be connected (e.g., welded) to at least one of the inner circumference (11) of the screen carrier frame (10) and the inner annular disks (14.1, 14.2 and 14.3).

[0045] In the embodiment illustrated in the drawing, the upper web (19a) is provided on the uppermost side, that is, on the upper side of the first inner annular disk (14.1), and the lower web (19b) is provided on the lower side of the third inner annular disk (14.3) at the lowest side.

[0046] At least two of the above webs (19a, 19b) are arranged parallel to each other on an inner circumference (11) facing one vibration motor (30) on an outer circumference (12), so that the radial stiffness of the screen carrier frame (10) can be further increased in the direction of the radial force generated by the two vibration motors (30).

[0047] The discharge hopper (50) is inserted vertically into the screen carrier frame (10) from the top and is fixed between the screen (20) and the upper rim (13) of the screen carrier frame (10). The discharge hopper (50) collects any material passing through the screen (20) and may have a discharge opening (51) for attaching, for example, bags, containers, etc. The discharge opening (51) may also lead toward a discharge conveyor.

[0048] It should be noted that the diameter of the inner rim (15.1) at the top of the first, second, and third inner annular disks is larger than the diameter of the inner rims (15.2, 15.3) of the two additional inner annular disks (14.2, 14.3). The inner rims (15.1, 15.2, and 15.3) of the inner annular disks (14.1, 14.2, and 14.3) are separated from the outer wall of the discharge hopper (50).

[0049] The hood (40) seals and covers the screen carrier frame (10) and the screen (20). It is provided with an inlet opening (41) for the product to be screened and at least one radial outlet (42) for solid material that is too large to pass through the screen.

[0050] The screen (20) is fixed between the upper rim (13) of the screen carrier frame (20) and the lower rim (43) of the hood (40) by means of a fixing means (60).

[0051] In a preferred embodiment, the discharge hopper (50), screen (20) and hood (40) are then stacked on the upper rim (13) of the screen carrier frame (10) and are all secured together by a fixing means (60) configured to pull the hood (40) against the screen carrier frame (10).

[0052] The vibrating screener (1) is seated on a spring assembly (70) that vertically supports the screen carrier frame (10).

[0053] In a specific embodiment, the vibrating screener (1) comprises: a screen carrier frame (10) having an inner circumference (11) and an outer circumference (12); a screen (20) for separating solid particles that extends horizontally within the screen carrier frame (10) and is vertically supported by the screen carrier frame (10); and one or more vibration motors (30) disposed on the outer circumference (12) of the screen carrier frame (10) and configured to generate a vibration component in a direction (z) perpendicular to the screen (20) and a vibration component in a radial direction (xy) of the screen (20). At least two inner annular disks (14.2, 14.3), each having an inner rim (15.2, 15.3) and an outer rim (16.2, 16.3), wherein each inner annular disk (14.2, 14.3) is attached to the inner circumference (11) of the screen carrier frame (10) by its outer rim (16.2, 16.3), and these two inner annular disks (14.2, 14.3) are spaced apart from each other in a parallel plane; The inner sleeve (17) is disposed within the screen carrier frame (10) and attached to the inner rim (15.2, 15.3) of the inner annular disk (14.2, 14.3), wherein the upper disk of the inner annular disk (14.2, 14.3) and the inner sleeve (17) provide an unbroken surface without any opening, and the lower inner annular disk (14.3) is provided with an opening (18) toward the external environment, thereby defining an annular channel (18a) open at the opening (18) together with the screen carrier frame (10). Optionally, this particular embodiment may be further modified by the features already described above, for example, by adding another inner annular disk (14.1) or by changing the number of vibration motors (30).

[0054] The vibrating screener (1) of the embodiment can meet the highest hygiene and safety standards in relation to pharmaceutical and food processing. In particular, the device (1) and its parts can be cleaned and disinfected without causing biological hazards. All surfaces can be reliably accessed with cleaning agents and disinfectants. Isolated empty spaces accessible only through capillary cracks, etc., where bacteria can proliferate virtually unhindered, are completely prevented.

[0055] In addition, by using a vibration motor (30) on the outer circumference (12) of the screen carrier frame (10), the risk of contamination by lubricating oil is minimized.

[0056] Due to the lightweight structure of the reinforced screen carrier frame (10), a relatively small vibration motor (30) can be used.

[0057] Radial forces are easily absorbed by the high radial rigidity of the reinforced screen carrier frame (10), so a large diameter of more than 800 mm for high throughput will be possible.

[0058] Therefore, the present invention provides a very simple solution to complex technical problems.

[0059] The present invention has been described in detail with reference to exemplary embodiments and further variations. However, the present invention is not limited thereto and includes all embodiments defined by the claims. In particular, technical features may be combined with one another as technically possible, even if not explicitly described above. The exemplary embodiments are intended to illustrate all aspects of the present invention merely for the sake of completeness of disclosure and to enhance understanding. However, this does not mean that all features described in combination must actually be combined with one another. On the contrary, it is explicitly stated that the detailed description is intended to encompass all technically possible sub-combinations and permutations of features of the present disclosure, which are omitted for reasons of brevity.

Claims

Claim 1 A vibrating screener comprising: a screen carrier frame having an inner circumference and an outer circumference; a screen for separating solid particles extending horizontally within the screen carrier frame and supported vertically by the screen carrier frame; one or more vibration motors disposed on the outer circumference of the screen carrier frame and configured to generate a vibration component in a direction (z) perpendicular to the screen; at least two inner annular discs, each having an inner rim and an outer rim, wherein each of the at least two inner annular discs is attached to the inner circumference of the screen carrier frame by its outer rim, and the at least two inner annular discs are spaced apart from each other in a parallel plane; and an inner sleeve disposed within the screen carrier frame and attached to the inner rims of two of the at least two inner annular discs, wherein the upper inner annular disc of the two inner annular discs and the inner sleeve provide an unbroken surface, while the lower inner annular disc of the two inner annular discs is provided with an opening toward the external environment. Screener. Claim 2 A vibrating screener according to claim 1, characterized in that the screen carrier frame has a substantially cylindrical shape. Claim 3 A vibrating screener according to claim 1, characterized in that the diameter of the outer circumference of the screen carrier frame is greater than 800 mm. Claim 4 A vibrating screener according to claim 1, characterized in that the outer rims of the at least two inner annular discs are welded to the inner circumference of the screen carrier frame. Claim 5 A vibration screener according to claim 1, characterized in that the inner sleeve is welded to the inner rim of the two inner annular discs. Claim 6 A vibration screener according to claim 1, wherein the at least two inner annular disks comprise a first, second, and third inner annular disk, and the diameter of the inner rim of the inner annular disk located at the uppermost of the first, second, and third inner annular disks is larger than the diameter of the inner rim of the remaining two additional inner annular disks. Claim 7 A vibrating screener according to claim 1, wherein a plurality of webs extend inward from the inner circumference of the screen carrier frame and perpendicularly to the at least two inner annular disks, and the webs are connected to the inner circumference of the screen carrier frame and at least one of the inner annular disks. Claim 8 A vibration screener according to claim 7, characterized in that at least two of the webs are arranged parallel to each other on the inner circumference facing one vibration motor on the outer circumference. Claim 9 A vibration screener according to claim 1, wherein each vibration motor has a rotation axis (A) that operates in a tangential plane of the outer circumference of the screen carrier frame, and the tangential planes of the vibration motors are parallel to each other. Claim 10 A vibration screener according to claim 9, characterized in that the rotation axis (A) of the tangent plane is inclined symmetrically with respect to the vertical axis (V) of the vibration screener. Claim 11 A vibrating screener according to claim 9, wherein the vibration motor is attached to the outer circumference of the screen carrier frame by a bracket that is fixed to the outer circumference of the screen carrier frame. Claim 12 A vibrating screener according to claim 1, characterized by a spring assembly that vertically supports the screen carrier frame. Claim 13 A vibrating screener according to claim 1, characterized in that the hood seals and covers the screen carrier frame, and the screen is fixed between the upper rim of the screen carrier frame and the lower rim of the hood by means of a fixing means. Claim 14 A vibrating screener according to claim 1, characterized by including a discharge hopper fixed between the screen and the upper rim of the screen carrier frame. Claim 15 A vibrating screener according to claim 9, characterized in that the vibration motor is provided with two, and the two vibration motors are arranged facing each other on the outer circumference of the screen carrier frame. Claim 16 A vibrating screener according to claim 6, wherein the outer rims of the first, second, and third inner annular disks are welded to the inner circumference of the screen carrier frame, and a plurality of webs extend inward from the inner circumference of the screen carrier frame and perpendicularly to the first, second, and third inner annular disks, and the webs are connected to the inner circumference of the screen carrier frame and at least one of the first, second, and third inner annular disks. Claim 17 A vibration screener according to claim 16, characterized in that two vibration motors are arranged facing each other on the outer circumference of the screen carrier frame, and at least two of the webs are arranged parallel to each other on the inner circumference facing one vibration motor on the outer circumference. Claim 18 A vibrating screener according to claim 17, further comprising a spring assembly that vertically supports the screen carrier frame, a hood that seals and covers the screen carrier frame, wherein the screen is fixed between the upper rim of the screen carrier frame and the lower rim of the hood by means of fixing means, and a discharge hopper fixed between the screen and the upper rim of the screen carrier frame.

Images