CN105618375A - Sieve separator and cleaning device of screen cloth thereof - Google Patents

Abstract

The invention discloses a cleaning device for a screen of a screening machine and the screening machine, wherein the cleaning device comprises a resonance piece and an elastic connecting piece (2), and the resonance piece is arranged on the screen (1) and is connected with the screen (1) through the elastic connecting piece (2). The invention also provides a screening machine. According to the invention, the resonance piece is arranged on the screen, and the frequency of the cleaning device is close to or equal to the self frequency of the screen machine by adjusting the mass and the rigidity of the resonance piece according to the principle of resonance effect, so that the resonance piece resonates or is close to resonance. Through above-mentioned technical scheme for resonance spare carries out patting by a maximum margin and does not need other power supply drives to the screen cloth, and not only simple structure is convenient for install and is maintained, can clear up the screen cloth effectively moreover, prevents screen cloth stifled hole, and makes the clearance to the feed inlet department of screen cloth and prevent stifled effect and obviously improve, can also improve the performance of sieve machine.

Description

Sieve separator and cleaning device of screen cloth thereof

Technical Field

The invention relates to the field of engineering machinery, in particular to a cleaning device for a screen of a screening machine and the screening machine.

Background

Currently, vibrating screens are commonly used to screen materials. Wherein, to the anti-blocking or clearance of screen cloth, adopt screen (ing) machine self power to realize beating with patting device in principle usually, perhaps utilize other power source systems to realize beating the function. However, the beating device is usually installed at the feed inlet, so the screen cleaning or anti-blocking effect at the feed inlet is not obvious, and the beating function realized by other power sources has the obvious screen cleaning or anti-blocking effect, but the system is complex and the economic cost is high.

Disclosure of Invention

The object of the present invention is to provide a cleaning device for a screen of a screening machine, which cleaning device does not require external power to clean the screen.

In order to achieve the above object, the present invention provides a cleaning apparatus for a screen cloth of a screen machine, wherein the cleaning apparatus comprises a resonance member and an elastic connection member, and the resonance member is connected with the screen cloth through the elastic connection member.

Preferably, the resonance member includes a plurality of resonance balls and rigid connection members respectively connected between two adjacent resonance balls, and the resonance balls are connected together by the rigid connection members.

Preferably, the plurality of resonance balls are arranged in a common straight line, the rigid connecting pieces are sequentially connected between two adjacent resonance balls, the number of the elastic connecting pieces is two, the two elastic connecting pieces are respectively connected with the two resonance balls at two ends and are all connected with the plurality of resonance balls in a common straight line, one end of each elastic connecting piece is connected with the resonance ball, and the other end of each elastic connecting piece is connected with the screen.

Preferably, a plurality of the resonance balls are arranged at equal intervals.

Preferably, each of said rigid links is of equal length.

Preferably, a plurality of the resonance balls are arranged in a common line in a width direction of the screen.

Preferably, the two said resilient connecting members are of equal length.

Preferably, the mass m of the resonance member is:

$m=\frac{c}{2\mathrm{\ζp}}$

where c is the damping coefficient of the elastic connection, ζ is the ratio of the actual damping of the screen system to the critical damping of the screen system, and p is the excitation frequency of the screen.

Preferably, the damping ratio zeta ranges from 0.2 to 0.4, and/or the damping coefficient c ranges from 100 to 1000.

Preferably, the stiffness k of the cleaning device is:

$k=\frac{\mathrm{cp}}{2\mathrm{\ζ}}$

where c is the damping coefficient of the elastic connection, ζ is the ratio of the actual damping of the screen system to the critical damping of the screen system, and p is the excitation frequency of the screen.

Preferably, the damping ratio zeta ranges from 0.2 to 0.4, and/or the damping coefficient c ranges from 100 to 1000.

The invention also provides a screening machine which comprises a screen, wherein the cleaning device is arranged on the screen.

According to the invention, the resonance piece is arranged on the screen, and the frequency of the cleaning device is close to or equal to the self frequency of the screen machine by adjusting the mass and the rigidity of the resonance piece according to the principle of resonance effect, so that the resonance piece resonates or is close to resonance. Through above-mentioned technical scheme for resonance spare carries out patting by a maximum margin and does not need other power supply drives to the screen cloth, and not only simple structure is convenient for install and is maintained, can clear up the screen cloth effectively moreover, prevents screen cloth stifled hole, and makes the clearance to the feed inlet department of screen cloth and prevent stifled effect and obviously improve, can also improve the performance of sieve machine.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic view of a cleaning apparatus on a screen according to a preferred embodiment of the present invention;

FIG. 2 is a mechanically simplified model schematic of forced vibration.

Description of the reference numerals

1 screen 2 elastic connecting piece

3-resonance ball 4 rigid connecting piece

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

In the present invention, unless otherwise specified, the directional terms used should generally be understood in conjunction with the accompanying drawings and in the context of actual use.

The invention provides a cleaning device for a screen mesh of a screen machine, wherein the cleaning device comprises a resonance piece and an elastic connecting piece 2, and the resonance piece is connected with the screen mesh 1 through the elastic connecting piece 2.

According to the solution of the invention, the resonant member is mounted on the screen 1 and has a natural frequency of vibration itself. In addition, the resonance member is also connected with the screen cloth 1 through the elastic connecting member 2, namely, the vibration of the screen machine is also transmitted to the resonance member through the elastic connecting member 2 so that the resonance member is forced to vibrate.

Thus, by adjusting the parameters of the cleaning device itself, for example by adjusting the overall mass and stiffness of the cleaning device, the resonant member resonates or approaches resonance when the natural frequency of the screen 1 is close to or equal to the frequency of the vibrations of the screen 1 transmitted to the resonant member by the resilient connecting member 2, at which the amplitude of the vibrations of the resonant member is at or near maximum amplitude. Therefore, the screen can be flapped to the maximum extent by the self-vibration of the resonance piece under the condition of not applying external power, so as to realize better effects of cleaning the screen and blocking holes.

According to the invention, the resonance piece is arranged on the screen, and the frequency of the cleaning device is close to or equal to the self frequency of the screen machine by adjusting the mass and the rigidity of the resonance piece according to the principle of resonance effect, so that the resonance piece resonates or is close to resonance. Through above-mentioned technical scheme for resonance spare carries out patting by a maximum margin and does not need other power supply drives to the screen cloth, and not only simple structure is convenient for install and is maintained, can clear up the screen cloth effectively moreover, prevents screen cloth stifled hole, and makes the clearance to the feed inlet department of screen cloth and prevent stifled effect and obviously improve, can also improve the performance of sieve machine.

Preferably, the resonance member includes a plurality of resonance balls 3 and rigid connection members 4 respectively connected between two adjacent resonance balls 3, and the resonance balls 3 are connected together by the rigid connection members 4.

In the preferred embodiment described above, the resonant member comprises a resonant ball 3 and a rigid connector 4. The rigid connecting piece 4 is connected between the adjacent plurality of resonant balls 3, so that the plurality of resonant balls 3 can be connected into one or more resonant ball groups, and the resonant piece can comprise one or more resonant ball groups. At least one resonant ball 3 in each resonant ball group is connected to the screen mesh 1 through an elastic connecting piece 2.

Due to the rigidity of the rigid connection member 4 itself, the resonant balls 3 connected by the rigid connection member 4 are connected as a rigid whole, that is, the resonant members are formed by the whole of the plurality of resonant balls 3 and the rigid connection member 4 connected between the plurality of resonant balls 3, and the natural frequency of the resonant members should be calculated by the whole of the plurality of resonant balls 3 and the rigid connection member 4 connected between the plurality of resonant balls 3. The vibration frequency and the vibration phase are the same between the plurality of resonant ball groups.

That is, the resonance ball 3 is arranged at the position needing to be cleaned on the screen cloth 1, and the resonance ball 3 is connected by the rigid connecting piece 4 according to practical application to form a resonance piece, and in the process of the screen machine working, the resonance ball 3 and the rigid connecting piece 4 in the resonance piece are integrally vibrated and flapped on the screen cloth, thereby playing the roles of cleaning the screen cloth 1 and preventing the holes from being blocked.

Preferably, the plurality of resonant balls 3 are arranged in a common straight line, the rigid connecting member 4 is sequentially connected between two adjacent resonant balls 3, the number of the elastic connecting members 2 is two, the two elastic connecting members 2 are respectively connected to the two resonant balls 3 at both ends, the two elastic connecting members 2 are connected to the plurality of resonant balls 3 in a common straight line, one end of each elastic connecting member 2 is connected to the resonant ball 3, and the other end of each elastic connecting member 2 is connected to the screen 1.

In the above preferred embodiment, as shown in fig. 1, it is preferable that three resonant balls 3 are connected in series by two rigid connecting members 4 to form one resonant member, and it is preferable that a plurality of resonant balls 3 are arranged at equal intervals, that is, three resonant balls 3 in the resonant ball group are arranged at equal intervals, so that the rigid connecting members 4 are connected between two adjacent resonant balls 3 and have equal lengths. Of the three resonant balls 3, two resonant balls 3 located at both sides are connected to the mesh 1 by elastic connection members 2, respectively. Preferably, the ends of the elastic connection members 2 are connected to the screen cloth 1 by means of connection members such as bolts, and preferably, the lengths of the two elastic connection members 2 are equal.

The plurality of resonance balls 3 may extend in any linear direction on the screen 1, and preferably, the plurality of resonance balls 3 are provided in a common line in the width direction of the screen 1.

The above is merely an example of a preferred embodiment of the present invention, and those skilled in the art can implement the technical solution of the present invention in various ways within the scope of the present invention, for example, the number of the resonant balls 3 in each resonant member can be set according to actual requirements.

According to the main idea of the invention, in order to allow the resonant member to vibrate under the effect of the vibration transmitted directly by the screen 1 and the vibration transmitted by the elastic connection member 2, in order to approach or achieve the effect of resonance so that the cleaning device can flap the screen with maximum amplitude, the arrangement of the resonant member can be derived from the principle of mechanical-vibration separation and calculation formula:

fig. 2 is a simplified mechanical model of forced vibration. In fig. 2, F (t) is fsingpt, where F (t) is the external force acting on the object over time, F is the magnitude of the external force, p is the excitation load frequency of the screen machine, and t is the time of forced vibration.

First, from the knowledge of mechanical-vibration, the system, when undamped, satisfies:

$m\stackrel{\·\·}{x}\left(t\right)+\mathrm{kx}\left(t\right)=0$

where x (t) is the forced vibration displacement of the object over time, m is the total mass of the cleaning device, and k is the stiffness coefficient of the elastic connector 2.

Wherein, it is madeThen it can be deduced that:

$w_n=\sqrt{k/m}---\left(1\right)$

in equation (1), w_nIs the cleaning device natural frequency.

The system shown in fig. 2 is a damped forced motion, in which:

k＝p²m

let x (t) be Xe^jpt，f(t)＝Fe^jptThen the system steady state response amplitude is:

$X=-\frac{F}{\sqrt{{(k-p^{2}m)}^2+p^2{c}^2}}---\left(2\right)$

and because of $r=\frac{p}{w_n}---\left(3\right)$

$\mathrm{\ξ}=\frac{c}{2{\mathrm{mw}}_n}---\left(4\right)$

$X=\frac{F}{k}---\left(5\right)$

Equations (1) to (5) are then associated to obtain:

$X=\frac{F}{k\sqrt{{(1-r^2)}^2+{\left(2\mathrm{\ξr}\right)}^2}}---\left(6\right)$

in the above equation, c is the damping coefficient of the elastic connection 2, r is the frequency ratio, i.e. the ratio of the frequency of the cleaning device to the natural frequency of the screen, ζ is the damping ratio, i.e. the ratio of the actual damping of the resonant system to the critical damping of the resonant system, and X is the system equivalent static displacement.

From the knowledge of the vibration, the force transmitted to the device via the screen is divided into two parts:

one part is the elastic driving force transmitted by an elastic connecting piece:

wherein,is the phase difference between the excitation and forced vibration.

The other part is damping force transmitted by the elastic connecting piece:

the maximum or amplitude of the force thus imparted to the device:

$X_T=\sqrt{{\left(\mathrm{kX}\right)}^2+{\left(\mathrm{cpX}\right)}^2}---\left(9\right)$

the (1), (3), (4) and (9) are combined,

$X_T=\sqrt{{\left(\mathrm{kX}\right)}^2+{\left(\mathrm{cpX}\right)}^2}=\mathrm{kX}\sqrt{1+{\left(2\mathrm{\ξr}\right)}^2}---\left(10\right)$

combine (6) and (10) to obtain

$X_T=\sqrt{{\left(\mathrm{kX}\right)}^2+{\left(\mathrm{cpX}\right)}^2}=\frac{F\sqrt{1+{\left(2\mathrm{\ξr}\right)}^2}}{\sqrt{{(1-r^2)}^2+{\left(2\mathrm{\ξr}\right)}^2}}---\left(11\right)$

When r is 1, i.e. w_nP, the device system resonates, and at this time

$\sqrt{\frac{k}{m}}=p---\left(12\right)$

Therefore, the following equations (3), (4), (5), (12) are derived:

the system quality m satisfies:

wherein the rigidity k of the device satisfies:the value range of the damping ratio zeta is 0.2-0.4; the value range of the damping coefficient c is 100-1000.

The invention also provides a screening machine which comprises the screen mesh 1, wherein the cleaning device is arranged on the screen mesh 1.

The preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications can be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.

It should be noted that the various technical features described in the above embodiments can be combined in any suitable manner without contradiction, and the invention is not described in any way for the possible combinations in order to avoid unnecessary repetition.

In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.

Claims (12)

1. A cleaning device for a screen of a screening machine, characterized in that it comprises a resonance member and an elastic connection member (2), the resonance member being connected to the screen (1) by means of the elastic connection member (2).

2. The cleaning device according to claim 1, wherein the resonance member comprises a plurality of resonance balls (3) and rigid connection members (4) respectively connected between two adjacent resonance balls (3), and the plurality of resonance balls (3) are connected together by the rigid connection members (4).

3. The cleaning device according to claim 2, characterized in that a plurality of the resonant balls (3) are arranged in a common straight line, the rigid connecting member (4) is sequentially connected between two adjacent resonant balls (3), the number of the elastic connecting members (2) is two, the two elastic connecting members (2) are respectively connected with the two resonant balls (3) at two ends, the two elastic connecting members (2) are connected with the plurality of resonant balls (3) in a common straight line, one end of each elastic connecting member (2) is connected with the resonant balls (3), and the other end of each elastic connecting member (2) is connected with the screen (1).

4. Cleaning device according to claim 3, characterized in that a plurality of said resonant balls (3) are arranged at equal intervals.

5. Cleaning device according to claim 4, characterized in that the length of each rigid connection (4) is equal.

6. A cleaning device according to claim 3, characterized in that a plurality of said resonance balls (3) are provided in a collinear manner in the width direction of said screen (1).

7. A cleaning device according to claim 3, characterized in that the two elastic connecting pieces (2) are of equal length.

8. A cleaning device as claimed in any one of claims 1 to 7, in which the mass m of the resonant member is:

$m=\frac{c}{2\mathrm{\ζp}}$

where c is the damping coefficient of the elastic connection, ζ is the ratio of the actual damping of the screen system to the critical damping of the screen system, and p is the excitation frequency of the screen.

9. The cleaning device of claim 8, wherein the damping ratio ζ ranges from 0.2 to 0.4 and/or the damping coefficient c ranges from 100 to 1000.

10. A cleaning device as claimed in any one of claims 1 to 7, characterized in that the stiffness k of the cleaning device is:

$k=\frac{\mathrm{cp}}{2\mathrm{\ζ}}$

where c is the damping coefficient of the elastic connection, ζ is the ratio of the actual damping of the screen system to the critical damping of the screen system, and p is the excitation frequency of the screen.

11. The cleaning device of claim 10, wherein the damping ratio ζ ranges from 0.2 to 0.4 and/or the damping coefficient c ranges from 100 to 1000.

12. A screening machine comprising a screen cloth (1), characterized in that the screen cloth (1) is provided with a cleaning device according to any one of the preceding claims 1-11.