GB1579545A

GB1579545A - Single type filter press

Info

Publication number: GB1579545A
Application number: GB1460977A
Authority: GB
Original assignee: NGK Insulators Ltd
Current assignee: NGK Insulators Ltd
Priority date: 1976-04-09
Filing date: 1977-04-06
Publication date: 1980-11-19
Also published as: DE2715781C3; FR2347077A1; DE2715781A1; FR2347077B1; DE2715781B2

Description

(54) SINGLE TYPE FILTER PRESS (71) We, NIPPON GAISHI KABUSHIKI KAISHA of No. 2-56, Suda-Cho, Mizuho-Ku, Nagoya City, Japan, a company organized according to the laws of Japan, 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 state ment:- This invention relates to a single type filter press comprising a plurality of vertically suspended filter plates, and an upwardly and downwardly movable filter cloth.

A single type filter press does not have a filter frame interposed between each two adjacent filter plates and has a filtering area per unit installation area which is larger than that of a double type filter press in which a filter frame is interposed between each pair of filter plates. A single type filter press is used for separating solids from liquids.

A conventional single type filter press which has been widely used has a centre feed mechanism for supplying slurry through a centre part of a filter plate. In such slurry supplying mechanism, a filter cloth is secured to a centre part of the filter plate by means of a metal fitting, so that it is extremely difficult to remove a dehydrated cake from the filter cloth. As a result, the dehydrated cake must manually or mechanically be scraped off the filter cloth.

A single type filter press comprising a movable filter cloth is also well known. Such a conventional filter press, however, has the disadvantages that it requires a number of parts and hence is complex in construction and liable to be damaged frequently, that it is difficult to adjust prior to operation, and that it is very expensive.

In addition, a filter cloth travelling mechanism in which each filter plate is provided with an independent filter cloth which is adapted to be taken up by independent motor is also well known. Such kind of filter cloth travelling mechanism, however, is required to provide an independent motor for every filter plate and hence not only requires a number of driving motors equal to that of the filter plates but also requires various kinds of complex mechanisms for synchronously moving all the filter cloths.

A further modified filter cloth travelling mechanism in which both ends of the filter cloth holding rod for suspending the filter cloth are connected to a lifting rail having a length which is substantially equal to the overall length between front and rear stationary frames of the filter press and the filter cloth is directly moved by raising and lowering the lifting rail has also proposed. In such a kind of filter cloth travelling mechanism, moving distance and speed of the filter cloth are just the same as those of the lifting rail, so that a large space is required for the movement of lifting rail. In addition, the filter cloth travelling mechanism is large in size and thus hinders the opening and closing of the filter plates.

It is an object of the present invention to provide a single type filter press which can minimize the above described drawbacks and problems which have been encountered with conventional filter presses, and which is simple in construction and which is reliable.

According to the present invention there is provided a single type filter press comprising a plurality of vertically suspended filter plates, a plurality of elongate guide rollers each arranged parallel to and rotatably mounted on the lower part of a respective filter plate, a respective pair of supporting columns secured to each alternate filter palte, each column of each pair being secured to a respective side of the upper end of the respective filter plate, a respective rotary shaft rotatably supported by each pair of supporting columns and provided with a pair of driving wheels, a respective filter cloth suspended as a U-shape so that it can cover both surfaces of each filter plate and guided by a respective elongate guide roller, a respective filter cloth holding rod adjacent each surface of each filter plate with said supporting columns provided thereon, each upper end of the legs of each U-shaped cloth being connected to a filter cloth holding rod with adjacent legs of adjacent cloths being connected to a common filter cloth holding rod, and a respective linear driving member engaged with each driving wheel and downwardly suspended therefrom, the lower ends of each linear driving member being connected to a filter cloth holding rod, whereby rotation of said driving wheels in first one and subsequently a second direction causes the filter cloths secured to the filter cloth holding rods to move upwardly and downwardly.

The invention will now be described in greater detail with reference to the accompanying drawings, wherein: Fig. 1 is a digrammatic front elevational view showing main parts of one embodiment of a single type filter press according to the invention, a part being shown in section; Fig. 2 is its diagrammatic perspective view of the filter press of Fig. 1; Fig. 3 is a diagrammatic perspective view showing a modified embodiment of a filter cloth holding bar for constituting a liquid supplying mechanism; Fig. 4 is a diagrammatic front elevational view showing another embodiment of a single type filter press according to the invention provided with a modified filter cloth travelling device; Fig. 5 is a digrammatic perspective view showing the filter cloth travelling device shown in Fig. 4; and Figs. 6 and 7 are diagrammatic end views showing other modified embodiments of the filter cloth travelling device.

Figs. 1 and 2 show one embodiment of a single type filter press according to the invention. In this embodiment, a plurality of filter plates 1, 1' are downwardly suspended from a pair of supporting rods connected across front and rear stationary frames of the filter press. Each filter plate 1, 11 is provided at its lower part with an elongate guide roller 3 having a diameter which is equal to that of a filter plate. The elongate guide roller 3 is arranged parallel to each filter plate 1, 11 and rotatably supported through a supporting arm 31 by each filter plate 1, 11. Each alternate filter plate 11 is provided at both sides of its upper end with a pair of supporting columns 4, 41 secured thereto and having a height which is substantially equal to that of the filter plate 11. The pair of supporting columns 4, 41 are connected with each other by means of a rotary shaft 6 provided with a pair of driving wheels 5, 51. At opposite surfaces of each filter plate 1, 1' is arranged a U-shaped filter cloth 2 guided by the elongate guide roller 3. The upper ends of the U-shaped filter cloth 2 are connected to filter cloth holding rods 7, respectively, which are downwardly suspended from the driving wheels 5, 51 through a pair of linear driving members 8, 81, in the form of a chain, belt, rope or cord, which are engaged with driving wheels 5, 51, respectively.

If the driving wheels 5, 51 are rotated in counter clockwise or clockwise directions, the driving members 8, 81 engaged with the driving wheels 5, 51 cause the half member of filter cloths 2 to move upwardly and the rest of filter cloths 2 to move downwardly in a seesaw movement.

As shown in Fig. 1, in the single type filter press according to the invention, it is preferable that each alternate filter plate 1 is provide at its opposite surface with a compression mechanism composed of a pair of diaphragms 9.

As shown in Fig. 2 a liquid feeding mechanism comprises a plurality of nozzle blocks 11 secured to a rotary shaft 10 extending along either side of the filter plates 1, 11 and rotatably mounted on front and rear frames of the filter press. Each of these nozzle blocks 11 is slidably mounted on the rotary shaft 10.

Each of the nozzle blocks 11 is provided with a hole 15 extended therethrough and adapted to form a liquid supply passage when all of the filter plates 1, 11 are closed. Each hole 15 is communicated with the front end of a nozzle 111 which is adapted to be inserted into a space formed between two portions 2, 21 of the filter cloth by rotating the rotary shaft 10.

In Fig. 3 is shown a modified embodiment of the liquid supply mechanism according to the invention. In the present embodiment, the liquid supply mechanism comprises a filter cloth holding rod 7 and a sticking up frame 17 connected with the rod 7 and provided at its top with a hole 12. When the filter plates are closed, all of these holes 12 function to form a slurry supply passage extending in parallel with the axis of the filter press. The hole 12 is communicated with a slurry supply opening 13 adapted to be terminated at a space formed between two adjacent portions 2, 2, of the filter cloth.

The single type filter press constructed as above described according to the invention will operate as follows. After all of the filter plates 1, 1' have been closed to remove liquid from the slurry to form cakes 14, the filter plates 1, 11 are separated from each other.

Then, all of the rotary shafts 6 are synchronously rotated in a counter clockwise direction as viewed in Figures 1-3. As a result, the driving wheels 5, 51 become rotated in the counter clockwise direction to move the driving members 8, 81 in a way such that the filter cloth holding rod 7 at the right side of the columns 4, 4, is moved upwaldly. So, the filter cloth holding rod 7 at the left side of the columns 4, 4, is moved downwardly. As the result, the two adjacent portions 2, 2, of the filter cloth connected to the downwardly moved filter cloth holding rod 7 are separated from each other at the guide roller 3. As a result, the space between the two adjacent portions 2, 21 of the filter cloth becomes enlarged, thereby separating the cake 14 deposited at the left side of the columns 4, 4 and discharging the cake 14 downwardly.

After all of the cakes 14 deposited at the left side of the columns 4, 41 have been discharged downwardly, the rotation of the rotary shaft 6 is stopped. Then, the rotary shaft 6 is rotated in clockwise direction so as to reverse the above described operation. As a result, all of cakes 14 deposited at the right side of the columns 4, 41 are released from the two adjacent portions 2, 2, of the filter cloth and discharged downwardly therefrom.

In Figs. 4 and 5 is shown an embodiment of a filter cloth travelling mechanism suitably applicable to the single type filter press according to the invention. In the present embodiment, provision is made of a pair of supporting beams 23 connected across front and rear stationary frames 21, 22 of the filter press. From the supporting beams 23 are suspended a plurality of filter plates 1, 11 each of which is provided at its lower end with a guide roller 3 rotatably mounted through a supporting arm 31 thereon. A filter cloth 2, 21 is guided by the guide roller 3 and connected at its upper ends to filter cloth holding rods 7, 71 respectively, Alternate filter plates 1 are each provided at their upper ends with two supporting columns 4, 41 for rotatably supporting a rotary shaft 6. To the rotary shaft 6 are secured two driving wheels 5, 51 around which are engaged a pair of linear driving members 8, 81 whose lower ends are secured to the filter cloth holding rods 7, 71 respectively.

The rotary shaft 6 is provided at its one end with a sprocket wheel 32. The supporting column 4 is provided at its one side with a second sprocket wheel 321 spaced apart from the sprocket wheel 32 secured to the rotary shaft 6. An endless chain 33 is engaged with the sprocket wheels 32, 321. In the present embodiment, in order to make the peripheral speed of the driving wheels 5 higher than that of the sprocket wheel 32, a diameter of the sprocket wheel 32 is made smaller than that of the driving wheel 5.

The endless chain 33 engaged with both the sprocket wheels 32, 321 is provided at its one portion with an idler roller 34 secured thereto.

The idler roller 34 is slidably engaged with a groove 36 of a lifting rail 35 which is channelshaped in section and movably mounted in the front and rear stationary frames 21, 22 of the filter press. The lifting rail 35 is operatively connected to an endless chain 39 so as to be moved upwardly and downwardly by driving the endless chain 39 from a motor M.

In Fig. 6 is shown a modified embodiment of the filter cloth travelling device shown in Figs. 4 and 5. In this embodiment, both the driving wheel 5 and the sprocket wheel 32 are not connected to the same common rotary shaft 6, but the driving wheel 5 is connected through intermediate gears 37, 38 to the sprocket wheel 32. The modified embodiment constructed as above described renders it possible to multiply a ratio of the diameter of the sprocket wheel 32 to the diameter of the driving wheel 5 by a ratio of the rotation of the intermediate gear 37 to the rotation of the intermediate gear 38 and to further increase the peripheral speed of the driving wheel 5 and that of the sprocket 32.

In Fig. 7 is shown another modified embodiment of the filter cloth travelling device shown in Figs. 4 and 5. In this embodiment, both the sprocket wheels 32, 321 are not disposed at one side surface of the supporting column 4 at the upper part of the filter plate 1, but are disposed at one side surface of the filter plate 1. The distance between the two sprocket wheels 32, 321 and the ratio of the diameter of the sprocket wheel 32 to the diameter of the driving wheel 5, etc. may suitably be selected by taking the speed ratio into consideration.

In the single type filter press constructed as described above according to the invention, the filter cloth portion 2, 21 opposed to the filtering surface of each of the filter plates 1, 11 is guided by the guide roller 3 provided at the lower end of each of the filter plates 1, 11.

In addition, the driving member 8, 8' engaged with the driving wheel 5 and connected to these two adjacent filter cloth holding rods 7 may be rolled up around the driving wheel 5.

In the filter cloth travelling device constructed as described above, for example, as in the case of the embodiment shown in Figs. 4 and 5, the filter cloth 2, 21 is guided by the guide roller 3 and connected at its upper ends to the filter cloth holding rods 7, 71, so that if all of the filter plates 1, 11 become open and separated from each other, the idler roller 34 slidably engaged with the groove 36 of the lifting rail 35 can slidably be moved in a horizontal direction. After all of the filter plates 1, 11 have been separated from each other, the lifting rail 35 can be moved upwardly or downwardly for a distance defined by the two sprocket wheels 32, 321. As a result, the endless chain 33 made integral with the idler roller 34 engaged with the groove 36 of the lifting rail 35 is moved to rotate the sprocket wheel 32 at a peripheral speed which is the same as the moving speed of the chain 33. Thus, the driving wheel 5 connected to the rotary shaft 6 and having a diameter which is larger than that of the sprocket wheel 32 becomes rotated at a peripheral speed which is higher than that of the sprocket wheel 32. So, the movement of the lifting rail 35 for a relatively short distance at a relatively low speed is transmitted to the filter cloth holding rod 7, 71 so as to move it for a relatively long distance at a relatively higher speed, thereby upwardly or downwardly moving the filter cloth 2, 21 at the higher speed and hence discharging the cakes.

As stated hereinbefore, in this embodiment, the filter cloth travelling device comprises the lifting rail 35 extending across the front and rear stationary frames 21, 22 of the filter press and slidably mounted thereon so as to be moved upwardly and downwardly and to travel all of the filter cloths 2, 21 each of which is separately associated with a respective filter plate 1, 11, The use of such lifting rail 35 is capable of converting the movement of the lifting rail 35 for a relatively short distance within the distance between the sprocket wheels 32, 321 at a relatively low speed with the movement of the filter cloth 2, 21 for a relatively long distance at a relatively higher speed. The lifting rail 35 moves within a narrow space, so that the mechanism is simple in construction, but can positively travel all the filter cloths 2, 21 synchronously. Thus, the filter cloth travelling mechanism is particularly applicable to the single type filter press.

As stated hereinbefore, in the single type filter press according to the invention, a pair of driving wheels 5, 51 are rotatably mounted on the upper end of the supporting column 4 secured to alternate filter plate and the rotations of the driving wheels 5, 51 in counter clockwise and clockwise directions cause the filter cloth 2, 21 secured to the filter cloth holding rod 7, 71 to move upwardly and downwardly, thereby automatically discharging the cakes 14. In addition, the single type filter press according to the invention comprises the filter cloth travelling mechanism which is simple in construction and reliable in operation. Thus, the single type filter press according to the invention may be used as a filter press for removing solids from various kinds of liquids, and hence is of great use in industry.

WHAT WE CLAIM IS: 1. A single type filter press comprising a plurality of vertically suspended filter plates, a plurality of elongate guide rollers each arranged parallel to and rotatably mounted on the lower part of a respective filter plate, a respective pair of supporting columns secured to each alternate filter plate, each column of each pair being secured to a respective side of the upper end of the respective filter plate, a respective rotary shaft rotatably supported by each pair of supporting columns and provided with a pair of driving wheels, a respective filter cloth suspended as a U-shape so that it can cover both surfaces of each filter plate and guided by a respective elongate guide roller, a respective filter cloth holding rod adjacent each surface of each filter plate with said supporting columns provided thereon, each upper end of the legs of each U-shaped cloth being connected to a filter cloth holding rod with adjacent legs of adjacent cloths being connected to a common filter cloth holding rod and a respective linear driving member engaged with each driving wheel and downwardly suspended therefrom, the lower ends of each linear driving member being connected to a filter cloth holding rod, whereby rotation of said driving wheels in first one and subsequently a second direction causes the filter cloths secured to the filter cloth holding rods to move upwardly and downwardly.

2. A single type filter press as claimed in claim 1, wherein each said alternate filter plate is provided with a compression mechanism composed of a pair of diaphragms.

3. A single type filter press as claimed in claim 1 or 2, and further comprising a liquid supplying mechanism including a rotary shaft rotatably mounted on front and rear stationary end frames of the filter press and extending along the side edges of said filter plates, a plurality of nozzle blocks secured to said rotary shaft and each operatively associated with a respective space between each pair of said filter plates, said nozzle blocks having a hole extending therethrough and forming a common liquid supply passage when said filter plates are closed together and a respective nozzle communicated with each said hole and adapted to be inserted into a space formed between two adjacent filter cloth portions.

4. A single type filter press as claimed in claim 1 or 2, and further comprising a liquid supplying mechanism including a plurality of upstanding members each provided with a filter cloth holding rod and at its top corner with a hole which when the filter press is closed forms a common liquid supply passage extending in parallel with the axis of the filter press, said hole communicating with a respective liquid supply opening formed in each said upstanding member and terminated at a space formed between the two adjacent filter cloths.

5. A single type filter press as claimed in any preceding claim, and further comprising a filter cloth travelling mechanism including a respective pair of spaced sprocket wheels arranged at the side surface of each alternate filter plate, and a respective endless chain engaged with each pair of sprocket wheels, a lifting rail extending between two stationary frames provided at opposite ends of the filter press and movably mounted along said frames in upward and downward directions and a respective idler roller secured to one portion of each endless chain, one of each pair of sprocket wheels being connected to the respective driving wheels such that the peripheral speed of said driving wheels is higher than that of said associated sprocket wheel, whereby the upward and downward movements of said lifting rail within the spaces formed between said sprocket wheels of each pair causes all of said filter cloths to travel at a

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. lifting rail 35 extending across the front and rear stationary frames 21, 22 of the filter press and slidably mounted thereon so as to be moved upwardly and downwardly and to travel all of the filter cloths 2, 21 each of which is separately associated with a respective filter plate 1, 11, The use of such lifting rail 35 is capable of converting the movement of the lifting rail 35 for a relatively short distance within the distance between the sprocket wheels 32, 321 at a relatively low speed with the movement of the filter cloth 2, 21 for a relatively long distance at a relatively higher speed. The lifting rail 35 moves within a narrow space, so that the mechanism is simple in construction, but can positively travel all the filter cloths 2, 21 synchronously. Thus, the filter cloth travelling mechanism is particularly applicable to the single type filter press. As stated hereinbefore, in the single type filter press according to the invention, a pair of driving wheels 5, 51 are rotatably mounted on the upper end of the supporting column 4 secured to alternate filter plate and the rotations of the driving wheels 5, 51 in counter clockwise and clockwise directions cause the filter cloth 2, 21 secured to the filter cloth holding rod 7, 71 to move upwardly and downwardly, thereby automatically discharging the cakes 14. In addition, the single type filter press according to the invention comprises the filter cloth travelling mechanism which is simple in construction and reliable in operation. Thus, the single type filter press according to the invention may be used as a filter press for removing solids from various kinds of liquids, and hence is of great use in industry. WHAT WE CLAIM IS:

1. A single type filter press comprising a plurality of vertically suspended filter plates, a plurality of elongate guide rollers each arranged parallel to and rotatably mounted on the lower part of a respective filter plate, a respective pair of supporting columns secured to each alternate filter plate, each column of each pair being secured to a respective side of the upper end of the respective filter plate, a respective rotary shaft rotatably supported by each pair of supporting columns and provided with a pair of driving wheels, a respective filter cloth suspended as a U-shape so that it can cover both surfaces of each filter plate and guided by a respective elongate guide roller, a respective filter cloth holding rod adjacent each surface of each filter plate with said supporting columns provided thereon, each upper end of the legs of each U-shaped cloth being connected to a filter cloth holding rod with adjacent legs of adjacent cloths being connected to a common filter cloth holding rod and a respective linear driving member engaged with each driving wheel and downwardly suspended therefrom, the lower ends of each linear driving member being connected to a filter cloth holding rod, whereby rotation of said driving wheels in first one and subsequently a second direction causes the filter cloths secured to the filter cloth holding rods to move upwardly and downwardly.

speed which is higher than the upward and downward movement of said lifting rail.

6. A single type filter press substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.