GB1577611A - Apparatuses for separating press plates particularly in filter presses - Google Patents

Description

(54) IMPROVEMENTS IN OR RELATING TO APPARATUSES FOR SEPARATING PRESS PLATES, PARTICULARLY IN FILTER PRESSES (71) We, IFO TEKNIK AB, a company duly organized and existing under the laws of Sweden, of 295 00 Bromolla, Sweden, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to an apparatus for separating press plates of filter presses having a number of such press plates carried coaxially with each other by parallel elongate supports and movable on said supports between closely adjacent positions during the filter pressing operation and spaced apart positions for emptying the filter press, in which apparatus a carriage is movable in parallel with the supports of the press plates and carries means for engagement with the outermost press plate on each occasion in order first to separate said press plate from an adjacent press plate and then to move it such a distance away from said adjacent press plate that a press cake can be removed manually or mechanically.

Use is made in industry of filter presses for reducing the liquid content of various media. The majority of these presses suffer from the common drawback that they have to be opened at regular intervals for removal of the pressed medium and/or exchange of filter press cloths. The work of separating the filter press plates is carried out manually and is physically very strenuous. Two workers are required for each press to separate the plates.

Most filter presses are of the kind described, but lately constructions have been developed, in which the plates are separated without contribution of manual work so that one person can empty the press on his own. The apparatus with which such modern filter presses are equipped for opening of the press plates cannot, however, be adapted to already existing presses of the kind described, but if this were possible each press would have to be equipped with an individual apparatus, which would entail very high reconstruction costs.

The present state of the prior art will appear from CH-PS 513,666 and GB-PS 1,442,265.

The object of the present invention is to permit mechanical opening of older filter presses at a relatively low price whereby such presses can be operated by only one worker who need not spend any effort greater than the operator of a modern press of this type.

To this end, the invention provides an apparatus for separating press plates of a plurality of parallel filter presses, each press having a number of such press plates carried coaxially with each other by parallel elongate supports and movable on said supports between closely adjacent positions during the filter pressing operation and spaced apart positions for emptying the filter press, comprising a carriage movable in parallel with the supports of the press plates on a beam assembly extending in parallel with the supports of the press plates and in turn movable on a beam assembly extending at right angles to said supports, said carriage being stoppable opposite each press plate and having engagement means including at least two wedge-shaped dogs which after the carriage has been stopped can be introduced between the outermost press plate and an adjacent press plate by pneumatic or hydraulic means in order first to separate the outermost press plate from the adjacent press plate and then to move it such a distance away from the remaining plate that a press cake can be removed manually or mechanically.

An embodiment of the invention will be described in greater detail hereinbelow with reference to the accompanying drawings in which Fig. 1 is a schematical side view of a filter press with an associated apparatus according to the invention; Fig. 2 shows a carriage which is part of the apparatus according to the invention and is viewed longitudinally of the press; Fig. 3 is a side view of the carriage.

Fig. 1 very schematically shows a conventional filter press 10 comprising a pair of horizontal parallel supports 11 which are carried by a frame 12 and which is turn carry a number of press plates 13. Thc press plates 13 form a pack which has end plates 14 at its opposite ends. The frame 12 also carries a hydraulic press mechanism (not shown) by which the plates 13 and the end plates 14 are brought together in the position shown in Fig. 1. Filter press cloths are arranged between the press plates 13, and normally, as shown in Figs. 2 and 3, each plate 13 has handle means 15 for moving the press plates 13 on the supports 11.

In short, a filter press functions as follows: A sludge is supplied to the brought-together press plates 13 (see Fig. 1) through a conduit (not shown) and is distributed in the spaces defined by each pair of press plates by way of central holes therein, the liquid phase of the sludge being discharged through the press cloths while the solid particles are retained in said spaces between the press plates. This process is conventional and well-known to those skilled in the art.

As already mentioned, emptying of the filter press is difficult and physically very strenuous since two workers have to separate press plate after press plate from the pack of plates. The manual press opening procedure can be carried out effortlessly by means of the apparatus shown in Fig. 1 above the filter press 10.

The apparatus according to the invention comprises a carriage 16 which at the top on each side has two pairs of wheels 17 which roll on beams 18 in the manner illustrated in Fig. 1. These beams 18 can be driven along transverse beams 20 with the aid of a suspension device 19 including rollers 21, whereby an apparatus according to the invention can serve a plurality of filter presses 10. The carriage 16 adapted to be driven along the beams 18 is shown in greater detail in Figs. 2 and 3.

The carriage 16 comprises a frame which at the top in addition to the wheels 17 carries a motor 22 with a slipping clutch 23 coupled to a gear wheel 29 which is in mesh with a rack 3 extending in parallel with the beams 18. By means of said motor 22 the carriage 16 can thus be moved along the beams 18 and, if it encounters some obstacle, the slipping clutch 23 will slip in conventional manner until the motor 22 is stopped, the carriage being retained in said position until the motor 2 is started again. The carriage has two downwardly depending portions 31 which are situated opposite one another transversely of the filter press and each of which carries an abutment 24 and has a wedge-shaped dog 25. The abutment 24 and the dog 25 are mounted on a shaft 26 and vertically pivoted between a lower position shown in Fig. 2 by full lines and an upper position shown in Fig. 2 by broken lines. Each of the two abutments 24 and the two wedge-shaped dogs 25 is operated by a piston and cylinder assembly 27 and a piston and cylinder assembly 28, respectively.

For pivoting the abutments 24 and the wedge-shaped dogs 25 and for starting and stopping the motor 22 a conventional type control device (not shown) is disposed on the carriage 16.

The apparatus, described above, for opening the press operates as follows. Assuming that the pressing cycle is concluded and that the press cakes shall be removed from the spaces between the press plates, firstly one end plate 14 is removed from the pack of press plates, as is shown in Fig. 3. This can be done with the aid of the hydraulic press mechanism of the filter press. With the carriage 16 occupying the position illustrated in Fig. 3 the motor 22 is started by actuation of a switch. The supply of current to the motor takes place via a time relay. Via the gear wheel 29 and the rack 30 the motor 22 moves the carriage 16 towards the outermost press plate 13 of the pack of plates.

When the motor 22 is activated the piston and cylinder assemblies 27 of the abutments 24 are also operated so that said abutments 24 are lowered into the position illustrated in Fig. 2 by full lines. The carriage 16 continues its movement towards the outermost press plate 13 until the abutments 24 strike said plate, whereby the carriage 16 is stopped. However, the time relay of the motor 22 is set such that the motor continues to rotate for some time, which it can do because of the slipping clutch 23. This procedure will ensure an exact setting of the carriage 16 relative to the outermost press plate 13. The motor is then stopped. The control apparatus then causes the abutments 24 to be raised and the wedge-shaped dogs 25 to be lowered by means of the pertaining piston and cylinder assembly 28. Because of the wedge shape of the dogs 25, the apices thereof facing the press plates 13, as is indicated by means ot a broken line in Fig. 3, said dogs can be introduced between the outermost press plate 13 in Fig. 3 and the adjacent press plate, so that these plates are slightly separated, whereby the press cake will come loose from either plate. After said separation the direction of rotation of the motor 22 is reversed and it is again started via the time relay, whereby the outermost press plate 13 is conveyed to the right in Fig.

3 over a distance determined by the time relay. Said press cake which has now been uncovered can be manually or mechanically caused to fall onto a conveyer beneath the filter press. A new cycle of operation is started automatically or manually in that the piston and cylinder assemblies are caused to raise the abutments 24 and the dogs 25, and the motor 22 is again started for moving the carriage 16 towards the press plate 13 which is now outermost. The abutments 24 are again lowered by the piston and cylinder assemblies 27 during said movement of the carriage and the cycle of operation described is repeated. In this way each plate 13 in the pack of filter press plates is loosened and carried away, and when a filter press has been emptied the entire plate separation apparatus with the carriage 16 and the beams 18 is moved on the beams 20 to a place above the next filter press.

It is a matter of course that the carriage 16 can be moved along the beams 18 in any other manner than what has been shown and that sensing means can be arranged in addition to or instead of the described device including a slipping clutch and abutments, in order to exactly set and stop the carriage 16 at desired points. For example, the motor can be stopped when the sensing means contacts the outermost plate.

Those skilled in the art will realize that it is possible by means of this simple and readily operated apparatus to avoid and to highly rationalize the manual work in opening filter presses.

WHAT WE CLAIM IS: 1. An apparatus for separating press plates of a plurality of parallel filter presses, each press having a number of such press plates carried coaxially with each other by parallel elongate supports and movable on said supports between closely adjacent positions during the filter pressing operation and spaced apart positions for emptying the filter press, comprising a carriage movable in parallel with the supports of the press plates on a beam assembly extending in parallel with the supports of the press plates and in turn movable on a beam assembly extending at right angles to said supports, said carriage being stoppage opposite each press plate and having engagement means including at least two wedge-shaped dogs which after the carriage has been stopped can be introduced between the outermost press plate and an adjacent press plate by pneumatic or hydraulic means in order first to separate the outermost press plate from the adjacent press plate and then to move it such a distance away from the remaining plate that a press cake can be removed manually or mechanically.

2. An apparatus as claimed in claim 1, characterised in that the carriage has at least one abutment which can be pivoted between a position in which it is lowered into the path of motion of the press plates on the supports, and a position in which it is raised from said path, and that the carriage is driven by a reversible motor thereon via a slipping clutch so that when approaching a press plate the carriage is stopped under slipping as the abutment engages the plate; the abutment being again raised after the carriage has been stopped.

3. An apparatus as claimed in claim 2, characterised in that the motor is engaged and disengaged by a timer.

4. An apparatus as claimed in claim 2, characterised in that the motor is engaged and disengaged by a sensing means placed on the carriage and adapted to sense the position of the carriage, in one case, with regard to a press plate not yet separated and, in the other case, with regard to an already conveyed press plate to stop and reverse the carriage movement.

5. An apparatus as claimed in claim 1 and substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (5)

1. **WARNING** start of CLMS field may overlap end of DESC **.

   3 over a distance determined by the time relay. Said press cake which has now been uncovered can be manually or mechanically caused to fall onto a conveyer beneath the filter press. A new cycle of operation is started automatically or manually in that the piston and cylinder assemblies are caused to raise the abutments 24 and the dogs 25, and the motor 22 is again started for moving the carriage 16 towards the press plate 13 which is now outermost. The abutments 24 are again lowered by the piston and cylinder assemblies 27 during said movement of the carriage and the cycle of operation described is repeated. In this way each plate 13 in the pack of filter press plates is loosened and carried away, and when a filter press has been emptied the entire plate separation apparatus with the carriage 16 and the beams 18 is moved on the beams 20 to a place above the next filter press.

   It is a matter of course that the carriage 16 can be moved along the beams 18 in any other manner than what has been shown and that sensing means can be arranged in addition to or instead of the described device including a slipping clutch and abutments, in order to exactly set and stop the carriage 16 at desired points. For example, the motor can be stopped when the sensing means contacts the outermost plate.

   Those skilled in the art will realize that it is possible by means of this simple and readily operated apparatus to avoid and to highly rationalize the manual work in opening filter presses.

   WHAT WE CLAIM IS: 1. An apparatus for separating press plates of a plurality of parallel filter presses, each press having a number of such press plates carried coaxially with each other by parallel elongate supports and movable on said supports between closely adjacent positions during the filter pressing operation and spaced apart positions for emptying the filter press, comprising a carriage movable in parallel with the supports of the press plates on a beam assembly extending in parallel with the supports of the press plates and in turn movable on a beam assembly extending at right angles to said supports, said carriage being stoppage opposite each press plate and having engagement means including at least two wedge-shaped dogs which after the carriage has been stopped can be introduced between the outermost press plate and an adjacent press plate by pneumatic or hydraulic means in order first to separate the outermost press plate from the adjacent press plate and then to move it such a distance away from the remaining plate that a press cake can be removed manually or mechanically.
2. 2. An apparatus as claimed in claim 1, characterised in that the carriage has at least one abutment which can be pivoted between a position in which it is lowered into the path of motion of the press plates on the supports, and a position in which it is raised from said path, and that the carriage is driven by a reversible motor thereon via a slipping clutch so that when approaching a press plate the carriage is stopped under slipping as the abutment engages the plate; the abutment being again raised after the carriage has been stopped.
3. 3. An apparatus as claimed in claim 2, characterised in that the motor is engaged and disengaged by a timer.
4. 4. An apparatus as claimed in claim 2, characterised in that the motor is engaged and disengaged by a sensing means placed on the carriage and adapted to sense the position of the carriage, in one case, with regard to a press plate not yet separated and, in the other case, with regard to an already conveyed press plate to stop and reverse the carriage movement.
5. 5. An apparatus as claimed in claim 1 and substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.