A vibrating screen
The vibrating screen design with two shafts and removable bearing cases simplifies maintenance and reduces costs by allowing easy assembly and disassembly, ensuring efficient elliptical movement for bulk material separation.
Patent Information
- Authority / Receiving Office
- AU · AU
- Patent Type
- Applications
- Current Assignee / Owner
- METSO BRASIL IND E COMML LTDA
- Filing Date
- 2024-06-12
- Publication Date
- 2026-07-23
Smart Images
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Abstract
Description
[001] This application is a further application for an invention disclosed in Australian patent application no. 2018382236, the disclosure of which is incorporated herein by reference. FIELD
[002] The present disclosure describes, amongst other things, a mechanical vibrator with a bearing case mechanism, which is able to be mounted on a vibrating screen for separating bulk material, and which is able to vibrate a screen deck of the vibrating screen. The mechanical vibrator is of a type in which a pair of bearing cases are mounted to a beam or beams, and the beam or beams is / are supported by the structural sidewalls of the vibrating screen. The bearing cases support the end portions of a pair of rotating shafts which are transverse to the longitudinal axis of the vibrating screen, and the end portions of the shafts carry eccentric weights. BACKGROUND
[003] The process of separating bulk grains or particles of different sizes in vibrating screens involves the passage of the bulk material along the screen deck of a vibrating screen, which is vibrated so that, with the displacement of the bulk material, smaller particles pass through the holes in the screen deck, to be separately released from the larger particles that are displaced over (i.e. they travel along and off the end of) the screen deck.
[004] The vibratory movement imparted to the vibrating screen, 2024203986 09 Jun 2026 and to its screen deck, causes the bulk material to be moved over (i.e. along) the screen deck and it also causes upward thrusts on the translating material, which helps to prevent particles that do not pass through holes in the screen deck from remaining stuck in the screen deck holes thereby obstructing the passage of other smaller particles through the screen deck holes.
[005] In one known vibrating screen construction, the screen deck is displaced (vibrated) with reciprocating linear movement, and with the direction (axis) of the reciprocating linear movement being in a forward and upward inclined direction relative to the screen deck. This movement is obtained by the provision of two transverse shafts, with their end portions rotatably supported on respective pairs of bearings, each pair of bearings being housed in a respective bearing case which is in turn secured through a respective sidewall of the vibrating screen.
[006] Each end portion of each shaft carries at least one eccentric weight, and the shafts are rotated in opposite directions, with the same frequency and in determined phases, which defines the inclination (i.e. the angular orientation) of the direction (axis) of the reciprocating linear movement relative to the plane of the screen deck.
[007] The efficiency of separation of a vibrating screen depends on several factors, including (among others) the thickness of the layer of bulk material being displaced on the screen deck and the residence time of the bulk material on the screen deck. In addition to these two factors, maintaining the holes in the screen deck in a non-obstructed condition should also be considered as this can also affect the efficiency of separation of the vibrating screen.
[008] The mat of bulk material which is transported over (i.e. which moves along) the screen deck may be moved linearly forward and also upward, intermittently and at a predetermined frequency, 2024203986 09 Jun 2026 to better revolve the bulk material and still move particles that are clogging holes in the screen deck upwardly and outwardly from (i.e. up and out of) the holes in the screen deck.
[009] Considering the factors mentioned above and relevant to vibratory screening of bulk material, another known vibrating screen construction was proposed in which the screen deck of the vibrating screen is displaced with elliptical movement / motion, with the major axis of the elliptical movement being disposed (i.e. oriented) in a direction which is inclined forwardly and upwardly relative to the screen deck. This elliptical movement is obtained, in this known vibrating screen construction, by the provision of three transverse shafts, with the end portions of each shaft rotatably supported in respective pairs of bearings, and one bearing in each pair of bearings is housed in a respective bearing case which is, in turn, fixed through a respective sidewall of the vibrating screen. The geometrical axes of rotation of the eccentric weights are arranged at or slightly above the center of gravity of the vibrating screen.
[0010] In the vibrating screen construction discussed in the previous paragraph, each end portion of each shaft carries at least one eccentric weight, generally of the same total mass, and two of the shafts are rotated in the same direction, opposite to the direction of rotation of the third shaft. All three shafts rotate with the same frequency and in determined phases, so as to define the inclination (i.e. the angular orientation) of the major axis of the elliptical movement, which (as described above) is oriented in a direction which is inclined forwardly and upwardly relative to the screen deck. The mass difference (that is, the net mass imbalance of the three rotating shafts) defines the dimensional relation between the major and minor axes of the elliptical movement.
[0011] Although the three-shaft constructive solution 2024203986 09 Jun 2026 described above produces the desired elliptical movement of the screen deck, it also requires the provision of three shafts, each shaft carrying (on the ends thereof) eccentric weights, and the three shafts must be synchronized by means of a greater number of gears. This constructive solution therefore results in a heavy mechanical vibrator, of larger dimensions and of relatively higher cost.
[0012] In order to simplify the construction of the vibrating screen, another constructive solution of mechanical vibrator was proposed with only two shafts, but still capable of producing, on the screen deck of the vibrating screen, elliptical displacement, with the major axis of the elliptical movement (again) inclined forwardly and upwardly relative to the screen deck. In this constructive solution, the elliptical movement is obtained by the provision of two transverse shafts, each with their end portions rotatably supported by bearings housed in bearing cases which are, in turn, secured through respective sidewalls of the vibrating screen.
[0013] In this constructive solution, each end portion of each shaft carries at least one eccentric weight with a different mass from that of the other shaft, and the two shafts are rotated in opposite directions, with the same frequency and in determined phases to define the inclination (i.e. the angular orientation) of the major axis of the elliptical movement. The difference in the masses of the eccentric weights, as between the two shafts, defines the dimensional relation between the major and minor axes of the elliptical movement.
[0014] The constructions discussed above can be found in the descriptions and drawings of BR patent documents PI0602585-4 and PI1105435-2.
[0015] Even though it provides a two-axis (i.e. a two-shaft) construction, which is lighter and simpler than three shafts, and 2024203986 09 Jun 2026 can therefore impart elliptical movement to the screen deck of the vibrating screen more efficiently, the third known construction above still has a deficiency in common with the other two previous solutions discussed above (i.e. in common with the first and second known constructions above), which results from the fact that the mechanical vibrator has its bearing cases mounted through medial regions of the opposing sidewalls (i.e. through the sidewalls) of the vibrating screen.
[0016] With the aforementioned constructions, it is very complex, time-consuming and costly to perform disassembly and assembly operations on the mechanical vibrator and / or its components, for example, for maintenance. Also, with the aforementioned constructions, such maintenance operations must generally be carried out, as a result of the structural incorporation of the mechanical vibrator into the vibrating screen (with the shafts of the mechanical vibrator mounted through the sidewalls of the vibrating screen), in highly polluted environments, making these operations even more problematic and requiring undesirable periods of operational interruption of the equipment.
[0017] Any reference to prior art in the background above or elsewhere in this specification is not, and should not be taken as, an acknowledgment or any form of suggestion that the referenced prior art forms part of the common general knowledge in Australia or in any other country. SUMMARY OF THE DISCLOSURE
[0018] Due to the drawbacks of vibrating screens that have mechanical vibrators with two or three shafts mounted through the opposing sidewalls of the vibrating screen, it is thought that it may be desirable to provide a vibrating screen with a mechanical 2024203986 09 Jun 2026 vibrator that is capable of imparting elliptical movement to the screen deck of the vibrating screen and to do so using only two shafts transverse to the screen, and which allows easy and quick assembly and disassembly operations of the mechanical vibrator relative to the structure of the vibrating screen.
[0019] In one form, albeit not necessarily the only or broadest form, the invention relates to a vibrating screen comprising: at least one screen deck defined between two screen deck sidewalls, the screen deck configured to support bulk material; a mechanical vibrator having two transverse shafts which rotate at the same rotation speed and in opposite directions, each shaft having end portions, and each end portion carrying at least one eccentric weight; at least one beam extending transverse to a longitudinal axis of the vibrating screen, wherein opposite ends of the or each beam are fixed to the respective screen deck sidewalls; wherein: the end portions of the shafts are supported by bearings mounted to one of two bearing cases such that each of the end portions is adjacent an end portion of the other shaft, and the bearing cases are removably fixed to the at least one beam; each of the eccentric weights is located on an outside of the bearing case that supports the end portion carrying that eccentric weight; a total mass of the at least one eccentric weight carried on each end portion of one of the shafts is different to a total mass of the at least one eccentric weight carried on each end portion of the other shaft; the two shafts rotate in determined phases to impart elliptical movement to the screen deck, the major axis of the elliptical movement having a forward and upward inclination; and the mechanical vibrator is mounted above a center of gravity 2024203986 09 Jun 2026 of the vibrating screen and displaced in a longitudinal direction relative to the center of gravity of the vibrating screen.
[0020] In another form, although again not necessarily the only or broadest form, the invention relates to a vibrating screen comprising: at least one screen deck defined between two screen deck sidewalls, the screen deck configured to support bulk material; a mechanical vibrator having two transverse shafts which rotate at the same rotation speed and in opposite directions, each shaft having end portions, and each end portion carrying at least one eccentric weight; at least one beam extending transverse to a longitudinal axis of the vibrating screen, wherein opposite ends of the or each beam are fixed to the respective screen deck sidewalls; wherein: the end portions of the shafts are supported by bearings mounted to one of two bearing cases such that each of the end portions is adjacent an end portion of the other shaft, the bearing cases are removably fixed to the at least one beam, and the respective ends of the at least one beam are fixed at or near a top edge of each of the respective screen deck sidewalls such that the bearing cases, when fixed to the at least one beam, are positioned above the top edges of the screen deck sidewalls; each of the eccentric weights is located on an outside of the bearing case that supports the end portion carrying that eccentric weight; a total mass of the at least one eccentric weight carried on each end portion of one of the shafts is different to a total mass of the at least one eccentric weight carried on each end portion of the other shaft; and the two shafts rotate in determined phases to impart elliptical movement to the screen deck, the major axis of the 2024203986 09 Jun 2026 elliptical movement having a forward and upward inclination.
[0021] Thus, the bearing cases with the shafts can be detached from the beam(s) without a need for internal disassembling of the vibrating screen.
[0022] In some embodiments, the vibrating screen may have two beams extending transverse to the longitudinal axis of the vibrating screen, each beam having opposite ends thereof fixed to the respective screen deck sidewalls. Where this is the case, the bearing cases may be removably fixed to both of the beams.
[0023] In certain embodiments, each of the bearing cases may include a pair of bearing sidewalls and each of the eccentric weights may be located outside the bearing sidewalls of the bearing case that supports the end portion carrying that eccentric weight.
[0024] Each end portion of each of the shafts may carry a gear, and each gear may engage with the gear carried by the adjacent end portion of the other shaft. In embodiments where this is the case, each gear may be housed inside one of the bearing cases between the bearing sidewalls, and possibly between the bearings supporting the end portion that carries that gear.
[0025] In some embodiments, at least one of the end portions of at least one of the shafts may be configured as a drive shaft.
[0026] It may also be the case, in some embodiments, that, for each of the shafts, the end portion on one end of the shaft is linked to the end portion on the other end of the shaft by an intermediate portion of the shaft. In such cases, for each of the shafts, the end portions may be connected to the intermediate portion by flexible couplings.
[0027] In some embodiments, the position where the mechanical vibrator is mounted, which may be above the center of gravity of the vibrating screen and displaced in a longitudinal direction relative to the center of gravity of the vibrating screen, may 2024203986 09 Jun 2026 balance the eccentric, longitudinal and transverse impulses on incoming and outgoing portions of bulk material.
[0028] In some embodiments, the two bearing cases and the shafts may be covered by a protective cowl. Also, each of the bearing cases may include an opening on a top side of the bearing case, and where this is the case, the or each bearing case and the shafts may be covered by the protective cowl.
[0029] In the forms of the invention summarised above, the two shafts have their end portions supported by bearings mounted to one of two bearing cases, which are removably fixed to one or more transverse beams the opposing ends of which are fixed to the screen deck sidewalls of the vibrating screen. Each of the end portions of a shaft carries at least one eccentric weight having a total mass different from the total mass of the eccentric weight carried at each of the end portions of the other shaft, and the shafts rotate in determined phases, thereby defining a forward and upward inclination (i.e. the angular orientation) relative to the screen deck of the major axis of elliptical movement imparted to the screen deck.
[0030] Therefore, in vibrating screens according to the forms of the invention summarised above, the rotation of the two shafts, each carrying a different weight from the other shaft, imparts a desired elliptical movement to the vibrating screen and its screen deck, with the dimensional ratio between the major and minor axes of the elliptical movement being determined by the difference in the eccentric mass as between the two shafts. In addition, the vibrating screen eliminates the fixation of the mechanical vibrator (and its shafts) through the sidewalls of the vibrating screen, with the bearings supporting the shafts of the mechanical vibrator instead being mounted to respective bearing cases, which are in turn mounted on the one or more transverse beams allowing the mechanical vibrator, including the bearing cases, the bearings 2024203986 09 Jun 2026 and the shafts, to be easily detachable for maintenance or replacement. BRIEF DESCRIPTION OF THE DRAWINGS
[0031] The invention will now be described with reference to the accompanying drawings, given by way of example only, of a possible embodiment of the invention.
[0032] Figure 1 shows a simplified perspective view of a vibrating screen provided with two screen decks arranged between two sidewalls and on which a mechanical vibrator is removably attached.
[0033] Figure 2 shows, schematically and simplified, a cross sectional view of the vibrating screen and mechanical vibrator shown in Figure 1.
[0034] Figure 3 shows, schematically and in a side view, a vibrating screen with a mechanical vibrator, according to the invention, with two transverse shafts rotating in opposite directions and at the same frequency, each carrying on its respective end portions a pair of eccentric weights having a total mass different from the total mass of the eccentric weights carried on the end portions of the other shaft. In Figure 3, the eccentric weights are shown in a first position corresponding to (i.e. which causes, at this point in the elliptical motion generated by the rotation of the mechanical vibrator’s shafts) longitudinal and upward displacement of the screen deck.
[0035] Figure 3A schematically shows the eccentric weights of the two shafts in the same position as shown in Figure 3.
[0036] Figures 3B, 3C and 3D schematically represent the eccentric weights of the two shafts, at positions corresponding to (i.e. which cause) the other three principal displacements of the elliptical motion generated by the rotation of the mechanical 2024203986 09 Jun 2026 vibrator’s shafts, namely, transverse and upward (3B), longitudinal and downward (3C), and transverse and downward (3D), respectively.
[0037] Figure 4 schematically shows a top plan view of the vibrating screen shown in Figure 3 and, in particular (albeit in addition to other things), it shows the two transverse shafts of the mechanical vibrator connected to each other by gears. DETAILED DESCRIPTION
[0038] As illustrated and already mentioned above, the invention relates generally to vibrating screens PV for sorting bulk material and, more specifically, to vibrating screens of the type comprising at least one screen element 10, generally in the form of an elongated chute and substantially U-shaped profile and having a screen deck 11 onto which is moved a continuous load of bulk material such as various ores, the screen deck 11 being defined between two sidewalls 12 of the vibrating screen PV.
[0039] As shown, the mechanical vibrator VM comprises a pair of shafts 20 which (when the mechanical vibrator VM is installed on the vibrating screen PV) extend transverse to the longitudinal axis of the vibrating screen 10, each having an end portion 20a carrying at least one eccentric weight 30.
[0040] In the particular construction illustrated (by way of example), the end portions 20a of the respective shafts 20 that are adjacent to each other are rotatably supported on bearings 40 which are mounted in the same bearing case 50 which is removably fixed on two beams 13, which extend transverse to the longitudinal axis of the vibrating screen PV. The opposite ends of the beams 13 are fixed to the sidewalls 12 of the vibrating screen PV, generally on the inner face of said sidewalls.
[0041] According to the illustrated construction, each bearing 2024203986 09 Jun 2026 case 50 comprises a pair of opposed sidewalls 51, and the end portions 20a of the two shafts 20 that are adjacent to each other are each supported on a pair of bearings 40, each bearing 40 being mounted on a sidewall 51 of the respective bearing case 50.
[0042] Preferably, each end portion 20a of each of the shafts 20 carries a pair of eccentric weights 30 (i.e. in this construction, each end portion 20a of each shaft 20 carries two eccentric weights 30) positioned externally to the respective pair of bearings 40, i.e., the two eccentric weights in each pair of weights on each end portion are mounted externally of, and to either side of, the opposite sidewalls 51 of the respective bearing case 50, and the weights are generally sized so as not to extend out further in a radial direction than the bearing case 50.
[0043] One of the shafts 20 is driven from any of one or more drive units (not illustrated). The end portions 20a of the shafts 20, on each side of the vibrating screen 10, are provided with gears 60 which allow the shafts 20 to rotate together with the same rotation speed but in opposite directions, as schematically illustrated in Figures 3A, 3B, 3C, 3D and 4.
[0044] Each of the end portions 20a of a shaft 20 carries a gear 60 that engages with a gear 60 carried by the adjacent end portion 20a of the other shaft 20, and the gears 60 on adjacent end portions 20a, which engage with one another, are housed within the same bearing case 50, between the two bearings 40.
[0045] Each of the end portions 20a of a shafts 20 carries at least one eccentric weight 30 with a total mass different from that of the at least one eccentric weight 30 carried by each end portion 20a of the other shaft 20, and because the shafts 20 are linked / engaged with each other by the gears 60, the shafts 20 are rotatably driven in opposite directions but at the same frequency (i.e. the same rotation speed) and in determined phases to thus 2024203986 09 Jun 2026 define the forward and upward inclination (i.e. the angular orientation) of the major axis of the elliptical movement that is imparted on the screen deck 11, as shown in figure 3.
[0046] The difference in the masses of the eccentric weights as between the two shafts 20 defines the dimensional ratio between the major and minor axes of the elliptical movement of the screen deck 11.
[0047] Figures 3 and 3A show the eccentric weights 30 in a first position corresponding to (i.e. which causes) elliptical, longitudinal and upward, displacement of the screen deck 11, whereas Figures 3B, 3C and 3D illustrate the eccentric weights 30 of the two shafts 20 in positions corresponding to (i.e. which cause) the other three principal displacements of the elliptical motion generated by the rotation of the mechanical vibrator’s shafts, namely, transverse upward (3B), longitudinal downward (3C) and transverse downward (3D), respectively, of the screen deck 11 of the vibrating screen 10.
[0048] In the illustrated (example) construction, the two bearing cases 50 are disposed on respective sides of the vibrating screen PV each near to a respective sidewall 12 thereof. With this construction, the end portions 20a of each shaft, or possibly only one of the two shafts 20, defines a drive shaft, and the end portions 20a are connected to each other by an intermediate portion 20b of the respective shaft 20, with the use of flexible couplings 20c.
[0049] With the proposed construction, all the constituent elements of the mechanical vibrator VM, including the two bearing cases 50 and the shafts 20, are covered by a protective cowl 70, which is removably fixed by any suitable means on the beams as shown in Figures 1 and 2.
[0050] For maintenance of the mechanical vibrator VM, in the particular construction depicted, all that is necessary is for 2024203986 09 Jun 2026 the protective cowl 70 and the bearing cases 50 with the shafts 20 to be easily detached from the beams 13, and this can be done without the need for internal disassembling of the vibrating screen PV.
[0051] The proposed construction therefore allows for the generation of elliptical movement of the screen deck 11 by using a mechanical vibrator VM with only two shafts 20 mounted on a pair of bearing cases 50, which are easily and quickly assembled and disassembled from the beams 13 (of which there are two in this example) of the vibrating screen PV.
[0052] In the particular (example) construction depicted in the figures, the mechanical vibrator VM is mounted at a position above the center of gravity of the vibrating screen PV and displaced in a longitudinal direction relative to the center of gravity of the vibrating screen PV. In fact, in the particular (example) construction depicted in the figures, the position where the mechanical vibrator is mounted, above the center of gravity of the vibrating screen and displaced in a longitudinal direction relative to the center of gravity of the vibrating screen, balances the eccentric, longitudinal and transverse impulses, on the feed (incoming) and outlet (outgoing) portions of bulk material in relation to the screen deck 11, allowing a substantially constant flow of bulk material from the feed end to the outlet end of the screen deck 11.
[0053] Although only one possible embodiment of the invention has been illustrated, it should be understood that changes in shape, number and relative arrangement of the component parts may be made without departing from the scope of protection defined in the claims accompanying this disclosure.
[0054] In this specification, the term ‘comprising’ is intended to denote the inclusion of a stated integer or integers, but not necessarily the exclusion of any other integer, depending on the 2024203986 09 Jun 2026 context in which the term is used. This applies also to variants of the term such as ‘comprise’ or ‘comprises’.
Claims
2024203986 09 Jun 2026CLAIMS :
1. A vibrating screen comprising:at least one screen deck defined between two screen deck sidewalls, the screen deck configured to support bulk material;a mechanical vibrator having two transverse shafts which rotate at the same rotation speed and in opposite directions, each shaft having end portions, and each end portion carrying at least one eccentric weight;at least one beam extending transverse to a longitudinal axis of the vibrating screen, wherein opposite ends of the or each beam are fixed to the respective screen deck sidewalls;wherein:the end portions of the shafts are supported by bearings mounted to one of two bearing cases such that each of the end portions is adjacent an end portion of the other shaft, and the bearing cases are removably fixed to the at least one beam;each of the eccentric weights is located on an outside of the bearing case that supports the end portion carrying that eccentric weight;a total mass of the at least one eccentric weight carried on each end portion of one of the shafts is different to a total mass of the at least one eccentric weight carried on each end portion of the other shaft;the two shafts rotate in determined phases to impart elliptical movement to the screen deck, the major axis of the elliptical movement having a forward and upward inclination; andthe mechanical vibrator is mounted above a center of gravity of the vibrating screen and displaced in a longitudinal direction relative to the center of gravity of the vibrating screen.
2. A vibrating screen comprising:2024203986 09 Jun 2026at least one screen deck defined between two screen deck sidewalls, the screen deck configured to support bulk material;a mechanical vibrator having two transverse shafts which rotate at the same rotation speed and in opposite directions, each shaft having end portions, and each end portion carrying at least one eccentric weight;at least one beam extending transverse to a longitudinal axis of the vibrating screen, wherein opposite ends of the or each beam are fixed to the respective screen deck sidewalls;wherein:the end portions of the shafts are supported by bearings mounted to one of two bearing cases such that each of the end portions is adjacent an end portion of the other shaft, the bearing cases are removably fixed to the at least one beam, and the respective ends of the at least one beam are fixed at or near a top edge of each of the respective screen deck sidewalls such that the bearing cases, when fixed to the at least one beam, are positioned above the top edges of the screen deck sidewalls;each of the eccentric weights is located on an outside of the bearing case that supports the end portion carrying that eccentric weight;a total mass of the at least one eccentric weight carried on each end portion of one of the shafts is different to a total mass of the at least one eccentric weight carried on each end portion of the other shaft; andthe two shafts rotate in determined phases to impart elliptical movement to the screen deck, the major axis of the elliptical movement having a forward and upward inclination.
3. The vibrating screen of claim 1 or claim 2, wherein the bearing cases with the shafts can be detached from the beam(s) without a need for internal disassembling of the vibrating screen.2024203986 09 Jun 20264. The vibrating screen of claim 1, 2 or 3, wherein the vibrating screen has two beams extending transverse to the longitudinal axis of the vibrating screen, each beam having opposite ends thereof fixed to the respective screen deck sidewalls.
5. The vibrating screen of claim 4, wherein the bearing cases are removably fixed to both of the beams.
6. The vibrating screen of any one of the preceding claims, wherein each of the bearing cases includes a pair of bearing sidewalls and each of the eccentric weights is located outside the bearing sidewalls of the bearing case that supports the end portion carrying that eccentric weight.
7. The vibrating screen of any one of the preceding claims, wherein each end portion of each of the shafts carries a gear, and each gear engages with the gear carried by the adjacent end portion of the other shaft.
8. The vibrating screen of claim 7, when claim 7 is dependent on claim 6, wherein each gear is housed inside one of the bearing cases between the bearing sidewalls.
9. The vibrating screen of claim 8, wherein each gear is housed inside one of the bearing cases and between the bearings supporting the end portion that carries that gear.
10. The vibrating screen of any one of the preceding claims, wherein at least one of the end portions of at least one of the shafts is configured as a drive shaft.2024203986 09 Jun 202611. The vibrating screen of any one of the preceding claims, wherein, for each of the shafts, the end portion on one end of the shaft is linked to the end portion on the other end of the shaft by an intermediate portion of the shaft.
12. The vibrating screen of claim 11, wherein, for each of theshafts, the end portions are connected to the intermediate portionby flexible couplings.
13. The vibrating screen of claim 1 or any one of claims 3-12 when dependent on claim 1, wherein the position where the mechanical vibrator is mounted, above the center of gravity of the vibrating screen and displaced in a longitudinal direction relative to the center of gravity of the vibrating screen, balances the eccentric, longitudinal and transverse impulses on incoming and outgoing portions of bulk material.
14. The vibrating screen of any one of the preceding claims, wherein the two bearing cases and the shafts are covered by a protective cowl.
15. The vibrating screen of any one of the preceding claims, wherein each bearing case includes an opening on a top side of the bearing case.
16. The vibrating screen of claim 15, when dependent on claim 14, wherein the two bearing cases and the shafts are covered by the protective cowl.