JPH04150908A - Scraper filter device - Google Patents

Abstract

PURPOSE:To contrive an accurate scraping-off of filter cake by a method wherein a number of immovable divided scraper pieces are attached to the inner surface of a spiral screw provided on the outside of a cylindrical filter body with their ends overlapped and held by the force of a spring into a slidable contact with the outer peripheral surface of the filter. CONSTITUTION:A rotary outer cylinder mechanism 3 is provided around and coaxially of a fixed cylindrical filter body 22 having a cylindrical outer peripheral filter surface 22F provided with an open filter hole 21Ac of a desired size. A spiral screw 41 whose outer end is fixed to the rotary outer cylinder mechanism 3 is so arranged as to permit its free rotation with its inner wall surface out of contact with the outer peripheral filter surface 22F. A number of arcuate spring-loaded scraper pieces 51 into which a scraper mechanism is divided are provided in the grooves 41M of the inner wall surface and fixed in their respective positions and held immovable in the groove direction by projecting parts 41T and biased by a spring 52 to a normal position wherein the inner peripheral surfaces of the divided scraper pieces 51 are placed in a slidable contact with the outer peripheral filter surface 22F. As a result, the filter cake can be scraped off the outer peripheral surface of the filter uniformly in its entirety.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is based on a plurality of spiral screws that are connected to a spiral screw that rotates along a flat filtering outer circumferential surface of a fixed filtering cylinder that has filtering holes on its outer circumferential surface. This invention relates to a scraper filtration device in which divided scraper pieces can perform a filtering operation without moving their respective arrangement positions.

[Conventional technology]

For example, the filtration of a cylindrical filter element known as Japanese Patent Application Laid-Open No. 2-214511 filed by the present applicant,
Devices that scrape off with a screw scraper installed on the outer periphery without contact are attached to the screw and the scraper, or to a support bar that is a separate member, so the scraps get stuck and grow in the area where they are attached, and eventually become inoperable. There was the inconvenience of becoming

Therefore, it is unsuitable for highly viscous fluids or fluids containing high filtrate content.

(Problems to be Solved by the Invention) In contrast to such conventional techniques, recently there has been an increase in demand for filtration treatment of highly concentrated and highly viscous fluids, and there has been a growing demand for effective removal of filter particles. It is coming.

Therefore, the present invention is based on the premise that a scraper is provided directly on the end face of a spiral screw, and attempts to solve the drawbacks of this scraper. In other words, when a single long scraper is used, as the sliding force of the scraper mechanism acting on the filtration peripheral surface increases, the degree of wear on the outer peripheral surface of the scraper mechanism progresses, and the spiral-shaped single long scraper increases. The length of the mechanism as a whole becomes shorter and moves along the direction of the rotation groove of the spiral screw in the shorter dimensional difference groove, so the non-contact part of the scraper mechanism gradually increases on the inflow side of the fluid to be filtered. This causes the inconvenience of moving.

An object of the present invention is to provide a scraper filtration device that does not allow the divided scraper pieces to move along the spiral grooves regardless of wear and tear, and can evenly filter and scrape the entire outer circumferential surface of the filtration surface. It is said that

(Means for Solving the Problems) This invention provides an inner surface of a spiral screw rotatably arranged in a non-contact manner on the outside of a fixed filter cylinder having a cylindrical outer peripheral surface with filter holes. The scraper mechanism is constructed by arranging a large number of spring-equipped split scraper pieces divided into arc shapes in the grooves, and preventing each of them from moving from a predetermined position by a movement prevention means, and the springs are used to prevent the split scraper pieces from moving from their respective predetermined positions. The inner circumferential surface of the scraper is pressed against the outer circumferential surface of the filtration filter so as to come into sliding contact with the outer circumferential surface of the filter, and the ends of the adjacent divided scraper pieces are overlapped with each other to prevent leakage of screw pressure. This solves the above problem.

[Effect]

During the process in which the fluid to be filtered is transferred by the spiral screw that rotates with the rotation of the rotating outer cylinder mechanism, the fluid to be filtered is subjected to the filtration action, passes through the N1IA hole, becomes a filtered fluid, enters the filter cylinder, and is released to the outside. taken out.

On the other hand, the filter scum that cannot be filtered is scraped off from the outer surface of the filter hole by the divided scraper pieces and removed from the end of the rotating outer cylinder mechanism.

By the way, the divided scraper pieces are held in a predetermined position by a movement prevention means, and their ends are overlapped, so as they rotate while sliding against the outer circumferential surface of the filtration, the inner surfaces are worn out and the arcuate length becomes shorter. Even if the spring pieces move, the spring pieces simply expand outward at the same position, and the non-contact area with the outer circumferential surface of the filter does not increase, and the filter particles are removed reliably.

〔Example〕

Hereinafter, a case will be described in which an embodiment of the present invention is applied to a multipurpose filtering device for tofu, fruit juice, konjac, and the like.

This scraper filtration device 1 is used vertically as shown in FIGS. A rotary outer cylinder mechanism 3 that is supported on a shaft and rotates while covering the outside thereof; a spiral screw mechanism 4 that is integrally held inside the outer cylinder mechanism 3 and surrounds the filtration mechanism 2 in a non-contact manner; The main structure includes a scraper s5 provided on the inner surface of the spiral blade 41 of the screw mechanism 4.

Note that a screw chamber 6 is formed by the outer cylinder mechanism 3 and the filter mechanism 2.

The filtration mechanism 2 includes a support cylindrical body 21 that is erected by a holding hole Wa formed in the bottom member wb of the container frame W and a flanged holder H fixed to the upper surface of the bottom member wb, and that also serves as a liquid passage.
An inverted pan-shaped top plate 22 is attached to the intermediate portion 21C of the support cylinder 21.
A and a ta cylindrical body 22 concentrically connected by a bottom plate 22B. Further, the support cylinder 21 has an injection port 21Ac for the liquid to be treated (hereinafter referred to as "undiluted solution") G at its upper end, and a partition wall 21W provided at the inner cavity position corresponding to the joint part of the top plate 22A. A plurality of stock solution distribution holes 21Aa are bored in the cylindrical wall of which the upper end portion 21A is located above, and the stock solution G is allowed to flow into the screw chamber 6.

In addition, a filtered fluid (hereinafter referred to as "pure liquid") J is applied to the intermediate portion 21C of the support cylinder 21 at an appropriate location on the cylinder wall.
A plurality of gathering holes 21Ca leading to the C lumen are bored. Further, the lower end portion 21B is closed by a bottom plug 21S, and a pure liquid discharge pipe 21E having a stop valve 21V is hinged to the cylindrical wall directly above the bottom plug 213.

Incidentally, in the filtering mechanism 2, the strut cylinder 21 may be formed without any vertically split portions in the structure of the filter passage cylinder 22.

As shown in FIG. 3, the filter cylinder 22 is carved on the outer periphery of the porous holding cylinder 24, with the flat bottom surface 23b of the wire 23 having an isosceles triangular cross section held on the outside, and with the sharp apex part 23c inside. It engages with the spiral groove 24m and wraps it,
A slit of a desired width is provided between adjacent wires 23 to form filtering elongated holes 24a, and a filtering outer circumferential surface 22F is formed by the wound wires 23.

Note that, instead of the wire 23, a wire having a semicircular or semielliptical cross section or a desired shape that can form a flat filtering outer circumferential surface may be used.

Furthermore, the filtration cylinder having the filtration outer circumferential surface can be formed of a material other than wire, for example, punched metal, mesh metal, etc., and as long as the outer circumferential surface is flat, the filtration structure is not specified at all.

The rotating outer cylinder mechanism 3 includes an upper cylinder body 31 having a top plate 31A.
and a dish-shaped body 32 that is externally fitted onto the lower end edge 31B of the upper cylindrical body 31.

The upper cylindrical body 31 is pivotally supported on the upper end 21A of the columnar column 21 via a packing 7A and a bearing 8A, while the dish-shaped body 32 is attached to the pure liquid discharge pipe 21E at the lower end 21B of the columnar column 21. It is pivotally supported above the section via a packing 7B and a bearing 8B.

The outer circumferential surface of the upper edge 32A of the dish-shaped body 32 that fits onto the upper cylindrical body 31 is interlocked with the drive groove wheel P of the electric motor M installed on the bottom member wb of the container frame W via the heald B. A driven groove portion 32P is formed. Further, the dish-shaped portion 32B of the dish-shaped body 32 forms a ring-shaped recess 32H,
At the bottom thereof, strainer discharge ports 32E with valves are arranged in well-balanced positions at circumferential angles of 120 degrees.

As shown in FIG. 4, the spiral screw mechanism 4 is composed of spiral blades 41 formed in a spiral shape with the pitch gradually decreasing as it moves downward, and a framework 42 in which the blades 41 are installed.

The framework 42 includes an upper ring frame 42A and a lower ring frame 42.
B is connected through three longitudinal members 42C to form a cylindrical shape. Then, the outer edge of the spiral blade 41 is integrated with each longitudinal member 42C by an appropriate means such as partial welding.

Note that both ring frames 42A and 42B are connected to the flow holes 4 for the stock solution G.
A large number of holes 2a are bored, and the ends of the spiral blades 41 are fixed.

Further, the spiral screw mechanism 4 includes an upper cylindrical body 31
The upper ring frame is integrally coupled with a set screw 43 passing through the cylindrical body 31. (If necessary, the lower ring part is also fixed with a set screw.) As shown in FIG. It consists of protrusions 41T provided at, for example, every 120 degrees of the circumference, and a plurality of divided scraper pieces 51 with leaf springs 52 loosely fitted therebetween.

As seen in FIG. 5, the divided scraper piece 51 has six protruding pieces 51T extending to the top surface of the protrusion 41T on both end faces 51F, and the adjacent six pieces 51T overlap each other. It is supposed to be done. Note that the arcuate length between both end surfaces 51F is slightly shorter than the dimension between the projections 41T.

Note that among the divided scraper pieces 51, those located at both ends of the spiral blade 41 have 6 holes on the outer end surface 51F.
It is not necessary to provide the piece 51T.

In addition, a leaf spring 52 attached to each divided scraper piece 51
A coil spring may be used instead.

Incidentally, each of the divided scraper pieces 51 of the above-mentioned scraper mechanism 5 is preferably made of a plastic material with excellent wear resistance, such as hard synthetic resin such as Teflon, but the material is not necessarily specified.

The scraper machine ja5 can also be formed as a divided scraper piece in which the high pressure side located on the solid content discharge side is molded from a material with higher wear resistance than the low pressure side on the inlet side of the fluid to be filtered.

The operation will be explained based on the above configuration.

A solid-liquid mixture of a desired stock solution G, for example, a soybean milk stock solution, is poured into the screw chamber 6 through the distribution hole 21Aa from the injection port 21Ac.
The rotary outer cylinder mechanism 3 is rotated by the electric motor M via the V-belt B.

Then, the raw liquid G that has entered the screw chamber 6 is forced downward in the screw chamber 6 by the twisting pitch of the spiral blade 41, and only the liquid that can pass through the long filter hole 24a of the filter mechanism 2 becomes pure liquid J. The pure liquid discharge pipe 21E enters the filter cylinder 22, further descends into the inner cavity of the intermediate part 21C of the support cylinder 21 through the nest hole 21Ca, and opens the blocking valve 21V.
taken from.

This type of injection stock G contains highly sticky and adhesive solids, and this solids tends to clog the long filter holes 24a and cause clogging of the filter mechanism 2. The scum is immediately scraped off by the divided scraper piece 51 of the scraper mechanism 5 that is in sliding contact with the outer peripheral surface of the ring-shaped recess 32H of the blood-shaped body 32 of the rotating outer cylinder mechanism 3.
Therefore, there will be no inconvenience caused by clogging. Incidentally, in order to remove the accumulated scum, the discharge port 32E is pushed open from below and stored in the hopper 9 without being strained at an appropriate time.

However, during the rotation of the spiral blades 41, the inner circumferential surface of each divided scraper piece 51 is in close contact with the filtering outer circumferential surface of the filter cylinder 2, so that it inevitably wears out.

However, even if the segmented scraper piece 51 is shortened due to wear, the protrusion 41T prevents the divided scraper piece 51 from moving along the spiral groove 41M. 6, which overlaps with the biasing force of the leaf spring 52 without causing any non-sliding contact points.
The sliding contact with the outer circumferential surface of the filter is always maintained normally by the piece 51T, and problems such as leakage of the pressure obtained by the rotation of the spiral blade 41 do not occur.

In the above embodiments, the means for discharging the oak scum is constituted by the ring-shaped recess 32H and the discharge port 32E, but these configurations are not necessarily specified.

It may also be constituted by a spring-loaded closure valve means.

Further, although one embodiment of the present invention has been described, it may be formed in a horizontal type, and it is possible to provide the present invention as a filtration device for use in all industrial fields.

〔Effect of the invention〕

According to this invention, a spiral screw is disposed outside a fixed filter cylinder having a flat outer circumferential surface of the filter, and a large number of divided scraper pieces, which cannot be moved by means of movement prevention means, are arranged on the inner surface of the screw and the ends thereof are overlapped. Since the structure is such that it is always in sliding contact with the outer circumferential surface of the filter due to spring pressure, it is possible to scrape off the filter particles reliably, and even if the arcuate length of the divided scraper pieces is shortened due to wear, the 1tLA outer circumferential surface Since there are no non-contact areas, efficient filtration can be achieved.

[Brief explanation of the drawing]

1 is a partially sectional front view showing an embodiment of the scraper filtration device according to the present invention formed vertically; FIG. 2 is an enlarged sectional view taken along line nn in FIG. 1; The figure is an enlarged perspective view with a part of the filter cylinder cut away, FIG. 4 is a schematic perspective view of the spiral screw mechanism, and FIG. The scraper piece is shown in a state in which it has been returned to its straight shape. Figure 1 is a plan view, ■ is a front view, and Figure m is a bottom view. 22...Filtering cylinder body 22F-...Filtering outer peripheral surface 24a =...Filtering long hole 41-...Spiral screw 41T...
...Protrusion 41M--Spiral groove 5--Scraper mechanism 51--Divided scraper piece 51T--6 pieces 52--Plate spring

Claims (2)

[Claims] (1) A concentric rotating outer cylinder mechanism is disposed outside a fixed filter cylinder having a cylindrical outer peripheral surface with filter holes of a desired size, and the outer end of the rotating outer cylinder mechanism is The inner surface of the spiral screw fixed thereon is rotatably arranged without contacting the outer circumferential surface of the filtration, and a spring-equipped divided scraper piece divided into a large number of circular arc-shaped parts as a scraper mechanism is prevented from moving in the groove of the inner surface. A scraper characterized in that the inner circumferential surface of the divided scraper piece is always urged and brought into sliding contact with the outer circumferential surface of the filtration surface at each predetermined location by means of the spring so as not to be movable in the groove direction. Filtration device. (2) The scraper filtration device according to claim 1, wherein the ends of adjacent divided scraper pieces are overlapped with each other to prevent leakage of screw pressure.